In the era of proteomics, high-throughput screening of posttranslational states of proteins, especially protein modifications such as phosphorylation is considered to be of utmost importance. However, current protein modification detection depends on either the combination of proteolysis and mass spectrometry, or time-consuming immunoassay that requires inevitable washing processes. As a way to rapidly assay protein modification, here we propose the use of Open Sandwich Immunoassay that detects antigen-dependent stabilization of antibody variable region (Fv). As a model, the heavy and light chain variable regions (V_H/V_L) of anti-phosphotyrosine antibody PY20 were used to evaluate its performance. When measured by phage display method, while wild-type Fv showed modest phosphotyrosine (PY)-dependent stabilization of ∼30%, a mutant with weak V_H/V_L interaction (HQ39R) showed markedly improved response of >200%. Using this mutant, two fusion proteins in which each variable region fragment was tethered to GFP color variant were made (V_H-YFP/V_L-CFP), to monitor PY-induced fluorescence resonance energy transfer (FRET) between them. As a result, PY-induced enhancement in FRET was successfully monitored in a homogeneous solution. The result indicates a possibility of rapid screening of tyrosine-phosphorylated proteins in vitro or in situ, and possibly in vivo, opening a way to real-time monitoring of various post-translational events in a cellular system.

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The simple Langmuir isotherm model is often used to describe the equilibrium behavior of protein adsorption to a wide variety of adsorbents. Estimates of the two adjustable parameters of the Langmuir model, q_m and K_d, are usually made by fitting the model equation to equilibrium data obtained from batch equilibration methods. In this work, the possibility of estimating q_m and K_d for the adsorption of bovine serum albumin to a cation-exchanger from batch kinetic data was investigated. A rate model based on the kinetic form of the Langmuir isotherm with three adjustable parameters (q_m, K_d, and a rate constant) was fitted to a single kinetic profile. The value of the saturation capacity q_m identified by this approach was in very close agreement with the q_m value determined from equilibrium data. However, the value of the dissociation constant K_d could not be retrieved from the kinetic profile as the model fit was insensitive to this parameter. Sensitivity analysis provided valuable insights into the identifiability of the three model parameters.

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A novel method for generating hydroxyl radicals, ·OH, was developed, by applying slightly negative electric potentials (-0.2 ∼ -0.8 V vs Ag/AgCl) to the surface of a metal in contact with a hydrogen peroxide solution containing a supporting electrolyte. Namely, ·OH radicals are generated at the surface by the electrolysis of hydrogen peroxide according to the equation, H₂O₂ + e- -> ·OH + OH-. In this study, the kinetics of the removal of a model proteinaceous soiling (ß-lactoglobulin, ß-Lg) adsorbed to a stainless steel surface by the H₂O₂-electrolysis treatment were investigated. The rate of removal of the adsorbed ß-Lg from the stainless steel surface during the treatment was monitored in situ by ellipsometry, and the dependencies of the removal rate on H₂O₂ concentration, the electric potential applied to the surface, and the concentration and type of supporting electrolyte were examined.

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A simulated moving bed (SMB) process has been developed to separate L-(+)-lactic acid from acetic acid, a major impurity in the fermentation broth of Lactobacillus rhamnosus. Poly (4-vinylpyridine) resin (PVP) was selected as the adsorbent. Adsorption isotherms and mass transfer parameters of the organic acids were estimated from single-column frontal tests. Experimental results show that the Langmuir isotherms obtained from the frontal tests can be used in the design of an SMB process to achieve 99.9% purity and 93.1% yield of lactic acid. The column profiles and effluent histories, however, deviate from rate model predictions based on the Langmuir isotherms. They agree more closely with the predictions based on a modified Langmuir isotherm for lactic acid. The standing wave design method for systems with modified Langmuir isotherms is developed in this study. Rate model simulations show that the process based on the modified design method can achieve high purity (>99.9%) and high yield (>99.9%). For this nonlinear system, accurate isotherm model and model parameters are needed in the design, and the zone flow rates must be closely monitored and controlled in order to ensure high purity and high yield in the SMB process.

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PEGylation (covalent attachment of poly(ethylene glycol) (PEG)) is an increasingly important process that extends the in vivo circulation half-lives of therapeutic proteins, thereby increasing their efficacy and reducing both the frequency and the level of dosage required for effective treatment. PEGylation is known to significantly increase the size of proteins, so size exclusion chromatography (SEC) is a logical candidate for analysis and purification. In this paper, the results of size exclusion studies are presented for several proteins, with molecular weights from 12.2 to 68 kDa, PEGylated with PEG's ranging from 2 to 40 kDa and having between 0 and 8 PEG groups attached. Results show that PEG maintains a constant surface area to volume ratio whether it is in free solution or attached to a protein surface, in the latter case doing so by adjusting the thickness of the PEG layer according to the native protein molecular size and the total amount of PEG attached. The thickness of the PEG layer, and therefore the size of the PEGylated protein, is shown to be independent of the number of PEG groups attached to the protein. It will be shown that the size of PEGylated proteins is quantitatively predictable from the native protein and total PEG molecular weights alone and that the elution volumes of PEGylated proteins in SEC can therefore be predicted. This allows not only the identification of PEGylated species by analytical SEC but quantitative design of production scale SEC for the separation of PEGylated proteins.

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Although very high performance separation of biomolecules such as protein isoforms is possible with ion-exchange and hydrophobic interaction chromatography, the fundamental mechanisms involved in ligand-protein interaction is still not clear. In this study, ligand-protein interaction was analyzed by three different methods, isothermal titration calorimetry (ITC), batch adsorption isotherm measurements and column gradient elution experiments. It was found that proteins having a rigid structure such as lysozyme and those having a soft (flexible) structure such as myoglobin have different interaction properties to the ligands of the base matrix. The latter shows a stronger hydrophobic interaction and greater binding affinity. The gradient elution data also showed that quite a large number of binding sites are involved, and in some cases the adsorption is irreversible (proteins are not eluted).

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Many biomolecules such as proteins, enzymes and metal ions could be solubilised effectively into the reverse micelle organic solvents. This opens the possibility of using the existing liquid-liquid extraction technology and utilizing the reverse micelles for large-scale extraction in downstream processing. So far, there has been very limited research on the use of the reverse micelle for antibiotics extraction. Thus, an attempt was made to use dioleylphosphoric acid (DOLPA) reverse micelle to extract antibiotics. It was found that pH, surfactant concentration, as well as antibiotic types and concentration have a significant effect on the solubilizing capacity of antibiotics in the DOLPA reverse micelles system. At optimum conditions, about 63 % of penicillin G could be extracted during the forward extraction, and 54 % in the backward extraction.

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One of the biodegradable plastics, poly- -caprolactone (PCL), was mixed with the composting material, and the quantity of CO₂ that evolved in association with the decomposition of the plastic during thermophilic composting was determined from the difference between the quantity of CO₂ evolution in the presence and the absence of the plastic. Ultimate degradability, defined as a molar ratio of carbon loss as CO₂ to the carbon contained in the plastic that have been added to the composting material, began to elevate about 72 h after the initiation of the composting, indicating that the PCL decomposition occurred vigorously after the middle stages of composting. The ultimate degradability of PCL reached approximately 43.4 % at the end of 7 days composting. The pH value for the composting with PCL was lower than that without PCL throughout the composting period except at the earliest stage of composting. In the composting with PCL, the concentration of NH₃, the greatest nuisance odor compound among the exhaust gases that evolve during the composting process, was half or smaller than that observed for the composting without PCL at the middle stage of composting, and NH₃ was not detected at the later stage of composting. It was thus found out that the PCL degradation causes the decrease in pH value of the composting material and the reduction of NH₃ evolution into exhaust gas.

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The potential of the gfp (green fluorescent protein) gene as a visible marker for tracking hydrogen-producing bacterium of Enterobacter aerogenes was examined. A gfp-and kanamycin-resistance gene-containing vector (pUCGK) was constructed and transformed into E. aerogenes. The fluorescence of the green fluorescent protein (GFP) expression was detected in this fluorescent bacterium under different conditions. Since GFP as a molecular reporter is restricted by its requirement for oxygen in the development of the fluorophore, fluorescence detection for the fluorescent strain grown aerobically and anaerobically was performed, respectively. The oxygen concentration for maturation of the GFP fluorophore in E. aerogenes and the fluorescence detection condition for the fluorescent strain were determined in the hydrogen production system in the present study. By using the GFP technique, cell concentration of E. aerogenes could be easily obtained through the detection of fluorescence intensity. These findings allow the gfp-harboring E. aerogenes to be quantified under an anaerobic condition. As far as we know, we are the first to apply gfp to E. aerogenes for analyzing the hydrogen production process.

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Chemotaxis is the movement organisms toward chemical attractants and away from chemical repellents. Pseudomonas aeruginosa has chemotactic responses to a wide range of chemical stimuli. In this study, chemotaxis to environmental pollutants and their derivatives such as aromatic and volatile chlorinated aliphatic compounds were investigated in P. aeruginosa using the computer-assisted capillary method. P. aeruginosa was found to be attracted by p-toluate, m-aminobenzoate, dinitrosalicylate, o-chlorobenzoate, catechol, 2,4-dichlorophenoxyacetate (2,4-D) and 2,4,5-trichlorophenoxyacetate (2,4,5-T). Volatile chlorinated aliphatic compounds including trichloroethylene, trichloroethane, tetrachloroethylene, and chloroform elicited negative chemotactic responses of P. aeruginosa. Chemotaxis assays of the P. aeruginosa cheR mutant revealed that cheR encoding a methyl-accepting chemotaxis protein (MCP) methyltransferase, suggesting that chemotaxis toward these compounds are dependent on MCPs. P. aeruginosa possesses 26 putative MCP genes on its genome. A series of mutants that have deletion-insertion mutations in individual mcp genes and examined for chemotactic responses to these attractants and repellents. All the mutants showed normal responses to theses compounds. This result suggests that multiple MCPs are involved in detection of each of these attractants and repellents like detection of inorganic phosphate, amino acids, and oxygen.

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To utilize kitchen refuse as renewable substrate for producing biodegradable poly lactic acid (PLA), it is critical to eliminate the initial L (+)/D (-) lactic acid contaminated in kitchen refuse and preserve glucose during removal of initial lactic acid. Several semi-anaerobic batch fermentations by P. shermanii were conducted with kitchen refuse and synthetic medium at various pH. Lactic acid was preferentially assimilated than glucose in kitchen refuse and synthetic medium at all pH conditions. P. shermanii exhibited diauxic growth without any obvious intermediate lag phase during sequential utilization of lactic acid and glucose. Effect of pH on specific growth rate of P. shermanii at kitchen refuse was more considerable than that at synthetic medium. According to decreasing pH, propionate yield was increased; 0.33g/g used lactic acid and glucose at pH 6.5 and 0.49g/g at pH 5.0. Acetic acid yield was also increased but not radically by each pH. The metabolites of pyruvate and succinate were significantly different by means of used substrates. By pH control from 6.5 to 5.0 after lactic acid consumption, growth of P. shermanii was entirely ceased and glucose could be preserved. This study indicates that removal of initial lactic acid by preferential substrate utilization of P. shermanii and glucose preservation by pH control may increase optical purity of lactic acid fermented from kitchen refuse medium.

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Waste bleaching earths from crude vegetable oil refining process contains approximately 40% of its weight as oil. Production of fatty acid alkyl esters by lipase-catalyzed alcoholysis of waste vegetable oil from oil processing industry with primary alcohols in an organic solvent system was investigated. Lipase from Candida cylindracea showed very stable in organic solvent having as high as its hydrophobicity. When n-hexane, diesel oil, and kerosene were used as organic solvent in alcoholysis of waste activated bleaching earth at 10% of lipase concentration, during the first 4 hours of reaction more than 80±6% (w/w) fatty acid alkyl ester with short chain length alcohols was attained. Effect of lipase concentration on maximum fatty acid methyl ester production rate (%/h) is experimentally represented as follow,
maximum fatty acid methyl ester production rate (%/h)=ae^bx
where a and b are constants, and x denote enzyme concentration (% of waste bleaching earth weight). Constant b in n-hexane, diesel oil, and kerosene was approximately similar. Three types of fatty acid alkyl ester were analyzed as biodiesel fuel. Standard properties were similar compared to diesel fuel, but sulfur content of fatty acid methyl ester was below 0.0001 % (w/w). Considering the blend of fatty acid methyl ester with diesel fuel, use of diesel oil or kerosene in fatty acid methyl ester production leads to reduce the production cost and these results show a promising reutilization method of industrial waste resources containing waste vegetable oils for the production of biodiesel.

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To immobilize lipase for the enzymatic reaction in an organic solvent, various functional grope (aniline(AN), diethyl amine(DEA)) were introduced onto porous hollow-fiber membrane by radiation-induced graft polymerization of glycidyl methacrylate and chemical modification. Lipase was immobilized on polymer brush by permeation of 0.5g/l lipase solution (0.01M phosphate buffer solution) outward through the pores of fibers and subsequent chemical cross-linking of lipase molecules adsorbed onto the grafted polymer brush with glutaraldehyde (Fig.1). When the hollow fiber grafted DEA was used as immobilizing material, (we define this fiber as DEA-fiber ) lipase was immobilized at the density of 1.06 kg-lipase/kg-fiber, which is equivalent to the degree of multilayer binding of 200. The enzyme activity was measured using 6 mM lauric acid and 12 mM benzyl alcohol dissolved in anhydrous isooctane. When substrate solution was permeated outward from the inside of DEA-fiber at a space velocity of substrate solution of 482 h^-1, the lipase activity of DEA-fiber was 8.9 mol/(h kg-lipase). The enzyme activity of native lipase was 0.38 mol/(h·kg-lipase) in a batch reactor. It is found that the lipase activity was 23 times higher than native lipase by immobilization onto hollow fiber grafted DEA.

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A lot of flocculants is widely used in the wastewater treatment process where the activated sludge was used. However, the influence of these flocculants on the expression of functional activity of the microorganism in the activated sludge is hardly examined. Then, in this study how poly iron influenced the nitrogen processing of ammonia-oxidizing bacteria (AOB) in the activated sludge was investigated by using water-quality test and the molecular biology technique (Real time PCR and T-RFLP). In the batchwise nitrification-denitrification process used activated sludge, it turned out that the excessive addition of poly iron into aerating tank was strongly inhabited the expression of amo (mRNA of the ammonia monooxygenase) by analyzed RT-PCR.

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The removal of nonylphenol from aqueous solution was examined using a culture broth of Coprinus cinereus as a source of peroxidase. Coprinus cinereus IFO 30628 was used to produce peroxidase. The productivity of peroxidase was significantly improved by the addition of hydrogen peroxide or 5-aminolevulinic acid. Nonylphenol was effectively removed by a peroxidase-catalyzed reaction using the culture broth. The removal efficiency was optimal between pH 7-8, 25-40°C and at a molar ratio of H₂O₂ to nonylphenol of about 7.0. To remove 1 mg/L nonylphenol, 0.5 U/mL peroxidase was required at pH 7 and 25°C. The estrogenic activity of the nonylphenol solution, which was estimated using ELISA method, was below detection limit and did not increase by the peroxidase treatment. The removal mechanism of nonylphenol is probably different from that of phenol and bisphenol A. Phenol and bisphenol A were removed from solution mainly by precipitation due to the peroxidase-catalyzed polymerization. On the other hand, the precipitate was not observed during the removal reaction of nonylphenol. It may be removed mainly by degradation.

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This study is mainly related to the characterization of a modified laccase from the Trametes species for use in the oxidative removal of phenolics in aqueous systems. An amphiphilic copolymer, polyalkyleneoxide-co-maleic anhydride was used as a modifier. The modified laccase displayed higher catalytic activity along with improved thermal stability. The modification resulted in a 20- to 10-fold increase in thermal stability at 25 and 40°C, respectively. The kinetic parameters of both the native and the modified laccases were determined by using 2,6-dimethoxyphenol as a substrate. The modified laccase was applied to remove a range of phenolic compounds including chlorophenols, dichlorophenols, trichlorophenols, xylenol, and cresol, which usually behave as pollutants of natural environments. The modified laccase exhibited a remarkably improved efficiency over that of the native laccase in terms of removing various phenolic substances. These results revealed that the enzymatic oxidation by the modified laccases is suitable for the efficient removal of phenolics in aqueous systems.

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Bioseparations engineering will be more important in biopharmaceutical companies as large scale production of biopharmaceutical drugs (especially antibody drugs) are now anticipated. Chromatography is the major unit process of the downstream processes. Usually very high purity and complete removal of unwanted contaminants such as viruses and pyrogens are required for the protein drugs. For these reasons two or more chromatography processes are involved in the downstream process. This makes the process complicated and expensive. Although the protein drugs are very high-value products, the optimization of the process will be required for the next few years in order to reduce the total cost.
Fine separation is usually not needed in food industries. However, because consumers concern healthy food, functional foods or healthy foods are now being extensively developed. Chromatography may be employed for producing new functional foods or new functional food materials. It is also claimed that removal of unwanted components by chromatography may play important roles in increasing the shelf life of the product or the effective usage of raw materials.
Some examples will be presented how to design typical bioseparation and food separation processes by chromatography. Similarities and differences will also be discussed.

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Sterilizing is extremely vital in food processing, where its effect is supposed to be calculated from the sterilizing temperature and time at the holding tube. However, flow behavior of direct steam injection heating inside the holding tube after the injection nozzle has been unclear, creating serious uncertainty as for the sterilization effect, leading to major risk in food processing. This study was essentially conducted to market sterilized foods by steam injection heating in the U.S.A. This article includes useful experimental and calculational results concerning the mixing length of steam and liquid foods in the holding tube to obtain the sterilizing effect accurately. As for experiment, the holding tube was made of transparent Teflon. Laser Doppler Velocimetry was used to measure the mixing length and velocity distribution in the tube. Measurements of the mixing length were successfully made, despite the extremely short time phenomena. CFD by Euler’s multiphase flow model to calculating the mixing length, the velocity and temperature distributions in the holding tube have been also considered to compare with the experiment. This part, or the mixing section, does not possess functionality as the sterilizing tube. Based on these experiment and calculation, the mixing length for a single nozzle type has become clearly obtained. As temperature distribution measured is also taken into consideration, a good estimation of real sterilizing effect can be made. An excellent consistency exists between sterilizing effect calculated based on these results and the thermal death rate of Clostridium Sporogenes inoculated in soybean milk in the sterilizers. Based on the temperature and holding time obtained from this study, the actual sterilizing effect can be now calculated without risk of a too small or an excessive margin of safety. Sterilizing condition based on these results was accepted by the FDA.

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Batch cultures of a microalga, Haematococcus pluvialis, were studied under various trophic conditions with addition of acetate as a carbon source and/or light irradiation. Under the mixotrophic condition (acetate + light), the morphological change from a growth flagellated cell to a resting cyst cell and the astaxanthin production occurred. The effects of the initial acetate concentration and the light intensity on cell growth and astaxanthin production were investigated. The appropriate culture condition for growth of flagellated cells was different from that for astaxanthin production of cyst cells. A two-stage culture system for the continuous astaxanthin production was constructed by connecting two reactors for growth and production in series. The subcultured cells were inoculated to the growth reactor at the start of the operation. The fresh medium with 1.2 g/dm³ acetate was continuously supplied to the reactor and the medium containing the cells from the growth reactor was fed to the production reactor. The light intensity in the growth and production reactors was 2300 and 4600 lux, respectively and the acetate of 0.12 g was added every day to the production reactor. Most of cells in the effluent from the growth reactor were flagellated ones, while those in the production reactor were cyst ones. The morphological change occurred in the production reactor. The astaxanthin concentration in the effluent from the growth reactor was almost zero, whereas that in the effluent from the production reactor was maintained at high value. This system permitted to continuously produce the cyst cells with high astaxanthin content.

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In addition to liquid foods and semi-solid foods, agricultural products such as vegetables and fruits are currently being dried and distributed to large food processing companies. The purpose of such food drying processes is not only to reduce the volume and weight of the products but also to improve the product stability (shelf life) whereas the product quality must be maintained during and after drying. Pre-drying treatments such as addition of sugars are needed for vegetable drying in order to avoid damages to tissue structures. In this study the water desorption behavior was investigated for various sugar solutions and vegetables. The desorption isotherms and water diffusion coefficients were determined by isothermal desorption or drying experiments. Most isotherms were well described by the Guggenheim-Andersen-de Boer (GAB) equation. The temperature dependence was different from food to food. Especially disaccharides such as sucrose showed a significant increase of the equilibrium water content at a given water activity (Aw) with lowering temperature. The water diffusivity of sucrose also decreased much more with lowering temperature compared with other food products. The results have shown that all pre-treatments are very effective at 50°C. Pre-treatments with sugar solutions increased drying rate either in carrot or potato drying process. Dipping in sugar solutions of samples decreased the equilibrium water content. The apparent diffusivity values for all potato samples were higher than those for carrot samples. The apparent diffusivity increased with treatment of sugar solutions in all samples. Untreated and blanched samples did not shrink markedly compared with samples treated with sugar solutions. In addition colors of treated samples with sugar solutions are visibly better than untreated and blanched samples.

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Microbial xylitol production from corn cob hydrolysates using Candida magnoliae, which has an ability to convert xylose to xylitol under microaerobic condition, was investigated to enhance the utilization of corn cobs. About 25 g-xylose/L solution was obtained from 100 g-corn cobs/L solution by hydrolysis using 1.0 % sulfuric acid at 121°C for 60 min. The hydrolysates were then used for xylitol production, however, the cell growth was strongly inhibited due to the byproducts including furfural and hydroxymethylfurfural generated during the acid hydrolysis of corn cobs. Therefore, charcoal pellets, which were produced from waste mushroom medium, were employed as adsorbent in order to remove the inhibitors in the corn cob hydrolysates. By the charcoal pellets treatment, only the inhibitors were selectively removed from the corn cob hydrolysates without affecting xylose concentration. Using the treated corn cob hydrolysates, C. magnoliae was successfully cultivated, resulting in the production of 18.7 g-xylitol/L from 25 g-xylose/L within 36 h. Since the xylitol production by C. magnoliae were strongly influenced by dissolved oxygen (DO) concentration, the effects of oxygen transfer rate (OTR) on xylitol production was then investigated using a computer-controlled jar fermentor. The results showed that the xylitol production occurred only when the OTR ranged from 0.5 mmol-O₂/L·h to 16.5 mmol-O₂/L·h. Maximum xylitol yield (0.75 g/g) and productivity (0.2 g/L·h) were obtained at the OTRs of 0.5 mmol-O₂/L·h and 4.9 mmol-O₂/L·h, respectively.

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The internal and external morphology of various spray-dried powders were investigated as a function of the operating conditions of the spray-dryer by using confocal laser scanning microscope (CLSM) and scanning electron microscope (SEM). The blend of arabia gum (GA) and maltodextrin (MD) solution, which is normally used in the encapsulated food industry, was prepared at 30% solid content of the mass ratio of GA and MD of 1 to 3. In order to make the powder particles visible by CLSM, fluorescein sodium was used to label the solid materials. The solutions were fed through an Ohkawara L-8 type spray dryer at different inlet air temperatures and atomizing speeds. An increase in the vacuole as well as the particle size was observed when the inlet air temperature was increased. Smaller vacuoles and lower yields of vacuoles were observed when using low atomization speeds. The density of powders decreased with an increase of the inlet air temperature as well as with an increase of the atomizing speed. Furthermore, the surface morphology presented smooth and shriveled particles for all powders, but deeper surface grooving for low inlet air temperatures. More grooves were observed by using a low atomizing speed.

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Decomposition of disaccharides consisting of two glucose residues or glucose and fructose or galactose residues was measured using a tubular reactor at various residence time under the condition of 160 to 260°C and 10 MPa. The decomposition processes were expressed by the Weibull equation for all the disaccharides at any temperature. The susceptibility to decomposition depended on the type of glucosidic bond and was related to an electrostatic potential charge on the oxygen atom in the bond. Detail studies for decomposition kinetics were performed for maltose and sucrose. A change of pH during the decomposition intensively affected the decomposition rate, which could be also expressed by autocatalytic equation for sucrose decomposition.

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The commercial production of xanthan gum is highly dependent on the type of carbon source used. Commonly, glucose is used as the carbon source for xanthan production due to its high yield of xanthan but the cost of the glucose can also be significant. Alternative should be considered for the large production scale of xanthan gum in industries to reduce the production costs. Therefore, this study evaluates the use of tapioca starch as the carbon source in fermentation due to its low cost and readily available source in Malaysia. There were two types of tapioca starch used in the fermentation: pure and hydrolyzed tapioca starch. The fermentation conditions were optimized such as period of fermentation, age of inoculum, pH, percentage of inoculum, temperature, and concentration of carbon source. It was found that the optimal period of fermentation was 96 hours, optimal age of inoculum was 48 hours, optimal pH was 7.0, optimal percentage of inoculum was 10%, optimal temperature was between 28°C and 30°C, and optimal concentration of carbon source was between 30g/l and 40g/l for fermentation medium, which using tapioca starch as carbon source and between 50g/l and 70g/l for fermentation medium, which using hydrolyzed tapioca starch as carbon source. The maximum xanthan yield was 22.36 g/l using hydrolyzed tapioca starch as carbon source. Thus, hydrolyzed tapioca starch could be recommended as a carbon source in fermentation of xanthan gum.

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LCA inventory data based on input-output tables was used to analyze the relationship between the self-sufficiency rate of food and CO₂ emission in Japan. For the food item i with the total consumption C_i [M\] and self-sufficiency rate x_i, the total amount of CO₂ emission consists of (1) domestic production of i, (2) production of industrial product j to be exported for the import of i, and (3) transportation to export j and import i. According to this model, an effective carbon emission coefficient, σ_eff,i was calculated for each food item i. Because of the low self-sufficiency rate of food (∼40%), the amount of carbon emission was proved to have substantially increased in Japan. The difference between the present C-emission and that by assuming 100% food self-sufficiency easily reached the COP3 goal to reduce CO₂ emission. This means that an increase in food self-sufficiency rate can be an effective option to reduce CO2 emission in Japan.

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We found that some kind of peptidyl linkers can work as peptidyl tags for microbial transglutaminase (MTG)-mediated protein heterodimerization. The Myc epitope (the amino acid sequence: EQKLISEEL) and the T7 epitope (MASMTGGQQMG) that were attached to the N-terminus of enhanced green fluorescent protein (EGFP) were found to serve Gln-tags (i.e. peptidyl tags that provide reactive Gln residues for MTG-mediated protein cross-linking). A calmodulin binding peptide (KRRWKKNFIAVSAANRFKKISSSGAL), the V5 epitope (GKPIPNPLLGLD-ST) and the Strep-tag II (WSHPQFEK) that were attached to the N-terminus of EGFP were found to be Lys-tags that provide reactive Lys residues for the enzymatic cross-linking. The specific Gln-Lys cross-linkage was formed through Gln- and Lys-tags by MTG and the major products were EGFP heterodimers. The reactivity of peptidyl linkers containing reactive Lys residue decreased when they were tethered to C-terminus of EGFP, indicating that the microenvironment or steric hindrance affects more the substrate recognition of MTG than their amino acid sequences. It was found that the insertion of a specific peptide sequence (FERQHMDS, a part of ribonuclease S-peptide) into a loop of EGFP could facilitate the protein cross-linking reaction. These results suggest that commercial peptidyl tags can be employed as specific cross-linkers for MTG-mediated site-specific protein ligation.

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The n-3 polyunsaturated fatty acids (PUFAs) are commonly known of their beneficial effects on the health. Nevertheless, their chemically reactive properties are a major cause of quality deterioration in many types of natural and processed foods. Therefore, a wide utilization in the food industry is not available. In this study, we examined the influence of emulsifiers on the oxidative stability of docosahexaenoic acid oil and esters from viewpoint of the emulsion droplet size. Docosahexaenoic acid oil (DHA oil) and its methyl ester (DHAME) were emulsified by using two types of emulsifiers; polyglycerol and gum arabic. The emulsion size was measured by laser-scattering particle analyzer. The emulsion was put in a reaction vessel, and a fluorescent oxygen sensor was set up to monitor the changes of the oxygen concentration in the headspace of the vessel. The emulsions prepared in this study were stable in size during the incubation for three days. It has been shown that autoxidation could be dependent on the type of emulsifier and the emulsion size. For DHA oil, larger size could protect more efficiently against oxidation independent on the types of emulsifiers used. On the other hand, for DHAME, the size of emulsion was less effective on the oxidation rate constant. The oxidation processes were successfully simulated by a mathematical model suggested.

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Along with the continual economic development with the annual GDP growth rate of 7% - 9%, the demand for energy increases rapidly in the mainland of China (hereafter referred to as China for convenience). According to the statistical data, the total primary energy production was 1603 Mtce (i.e. 1122 Mtoe) in China in 2003, which increased by 11.0% compared with 2002. In the total primary energy production, raw coal was 1667 Mt with the increase rate of 15.0% and crude oil was 170 Mt with the increase rate of 1.8%. Based on estimation, the total energy consumption was 1678 Mtce in China in 2003, which increased by 10.1% compared with 2002; where raw coal was 1579 Mt with the increase rate of 13.6% and crude oil was 252 Mt with the increase rate of 12%. In 2003 China had the net import of 97.41Mt crude oil and product oil, which increased by 36.4% compared with 2002.
It is well known that coal is the main energy source in China. Although the portions of coal in total production and consumption of energy trend to be smaller, coals maintain the first place in the energy sector of China. The total energy production and the total energy consumption of China and their constitutions from 1991 to 2001 are shown in Table 1 and Table 2 respectively.

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A statistical analysis of the ground level ozone from ten monitoring sites of nine selected cities of the Mie Prefecture of Japan was done to investigate the diurnal, weekdays and weekends, seasonal, and annual patterns for the period of 1991-2001. Results showed that all the cities exceeded the standard limit (60 ppb) with frequency ranging from 0.74% to 15.91% and 2.31% to 32.84% respectively of all hourly and the peak hourly (12.00-18.00) observations. An upward trend in ozone exceedance was observed in all the sites while maximum exceedance occurred in Yokkaichi, Tsu and Toba. Short term diurnal analysis showed no distinct pattern. However, long term patterns shows that a peak level was observed at about 13.00-15.00 hours. Significant differences between the diurnal cycles in the different sites may be attributed to local weather, and potential for photochemical conditions. Weekdays and weekends pattern of ozone level in peak months showed significant differences in different stations for different months. Generally higher level of ozone was found on Friday in all stations. Diurnal distribution of both yearly and monthly averaged data showed distinct pattern with a peak period between 11.00 to 18.00 hrs and seasonal fluctuations with relatively higher level of ozone during April to September mainly attributed to potentiality of local photochemical production and favorable meteorological conditions. An upward trend in yearly averaged ozone distribution was observed in all the cities that ranged from 15.87% to 40.21% between 1991 and 2001. A stepwise multiple-linear regression analysis showed significant correlations between ozone and its precursors and meteorological parameters. The determined regression models for different stations could facilitate to explain the factors involved in ozone level productions.

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A novel separation process of condensable gases from the gaseous mixture with non-condensable gases using surface flow and capillary condensation in porous inorganic membranes was proposed. The concept was applied to the enrichment of condensable greenhouse gases such as hydrofluorocarbons (HFCs) and sulfur hexafluoride (SF₆) from mixtures with nitrogen. These gases are occasionally used as mixtures with non-condensable components such as nitrogen, and therefore, an enrichment process of these gases would be necessary for recycling or reuse. Because of their larger sizes and molecular weights, enrichment of these gases from nitrogen by molecular diffusion or molecular sieving mechanism would be difficult. Condensable properties of these gases could enhance the surface transport mechanism such as surface flow and the transport of capillary condensate phase, whereas the transport of the non-condensable component would be retarded due to the decrease in the effective pore size by the adsorbed molecules or capillary condensate. Thus, a significant improvement in the separation performance would be anticipated by using the surface transport mechanisms. Experimental studies were conducted using porous Vycor glass membrane (4 nm pore size) to investigate the separation performances under various conditions. The results indicate that HFC-134a was highly enriched, especially under high-pressure conditions close to the capillary condensation pressure. The proposed separation process was evaluated in terms of the energy consumption as well as the separation performance with the conventional processes such as liquefaction process.

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In the previous report (AIChE J., 50, 871-878, 2004), a new type of the injection method of liquid CO₂ by a static mixer was proposed by the present authors for the direct ocean disposal of CO₂ at the intermediate depths (500-1500 m). The static mixer is effective for producing liquid CO₂ drops with uniform size distribution, and would have advantages of the drop size control over simple nozzle injection methods. In this study, the mixing behavior of liquid CO₂ and water and its effects on the CO₂ drop formations in the Kenics type static mixer was observed in a laboratory-scale experimental apparatus simulating the intermediate ocean conditions. It was found that the size reduction and uniformalization of the liquid CO₂ drops were mainly conducted at the first 2 element at the upstream side of the mixer. After that, the size and its deviation decreased quite gradually without coalescence of the drops.

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East Asia is one of the most developing regions and thus aerosol emissions are increasing. We measured aerosols at Fukue Island to understand the chemical composition of aerosol in East China Sea. An instrument we deployed was an Aerosol Mass Spectrometer (AMS) produced by Aerodyne Research Inc. The non-refractory chemical components of the PM1.0 aerosols are analyzed by a quadrupole mass spectrometer. Sulfate and organics were the dominant species. Time-of-Flight analysis shows that the size distributions of organics were similar to that of sulfate for the long-range transportation. This suggests that aerosols are internally mixed. The ratio of sulfate to organics was high when the air came from Chinese continent, while it was low when the air came from either Korea or Japan. Case studies suggest that organics are internally mixed with sulfate when it is oxygenated.

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Desulfurization reactions of a levitated single Na₂CO₃ droplet under high humidity were followed by electrodynamic balances (EDB) coupled with a Raman spectroscopy. The changes in weight and chemical composition of the single droplet were measured by DC levitation voltage applied to EDB and Raman spectra, respectively. The reaction product between SO₂ and aqueous solution droplet of Na₂CO₃ depended on exposure time of SO₂ gas in EDB chamber. The Raman spectra show that the product was nearly all Na₂SO₃ for short exposure time, but for long exposure time, the addition of SO₂ to Na₂SO₃ led to NaHSO₃ (or NaS₂O₅) as final product. And the produced NaHSO₃ (or NaS₂O₅) particle turned back to Na₂SO₃ through the emission of SO₂ gas under high humidity in the absence of SO₂. Gravimetric analysis based on the DC levitation voltage also indicated that a series of above reactions occurs under desulfurization reaction using the desulfurizing reagents containing Na. It has been demonstrated that EDB was a powerful tool for the kinetic studies of fine droplet such as desulfurization.

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Carbon dioxide capture technology using ceramic absorbent (lithium silicate) has been developed by Toshiba Corporation and Toshiba Mitsubishi-Electric Industrial Systems Corporation to reduce CO₂ emissions and help alleviate global warming. A system containing a steam reforming catalyst and a CO₂ absorbing ceramic is being considered for application to an industrial-scale boiler system. The following reactions take place in this system.
Reforming reaction : CH₄ + H₂O = CO + 3H₂ - 209 kJ
Steam shift reaction: CO + H₂O = CO₂ + H₂ + 44 kJ
Absorption reaction : CO₂ + Li₄SiO₄ = Li₂CO₃ + Li₂SiO₃
The carbon from the fuel (natural gas) is removed in the initial step and hydrogen-rich gas is fed back to the boiler system as fuel. This system has the following 3 advantages: (1) the CO₂ removal efficiency is higher than in a post-combustion capture system, because the CO₂ concentration is higher than flue gas, (2) the reforming reaction can be carried out efficiently at a lower temperature because the reforming reaction equilibrium shifts to the right side as a result of CO₂ absorption and (3) the energy consumption is lower because part of the energy required for the endothermic reforming reaction is obtained from the energy released by the exothermic CO₂ absorption reaction. To demonstrate the feasibility of this CO₂ removal system, the reaction efficiency of a packed-bed reactor containing a reforming catalyst and absorbing ceramic was studied.

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This paper focuses on the emission behaviors of Pb, Cd and Cr during the sewage sludge combustion using a 2 m tall, 40 mm inner diameter electrically heated drop tube furnace. Equilibrium calculations were carried out before to predict the tendency of these trace metal emissions as the same conditions of experiments. The potential use of sorbent to manage emissions of Pb, Cd and Cr for the sewage sludge combustion was also tested. Experimental procedures involved baseline runs of sludge alone and a number of runs with the kaolin addition at 1073, 1148 and 1223K. The sample was collected by the aerosol size fractionation system composed of a water-cooled sampling probe with rapid N2 quenching and a Low Pressure Impactor (LPI). Particle size distributions (PSDs) indicate that most of Pb and Cd are contained in the fine particles (less than 1µm). However, Cr compounds are not enriched in the fine particulates. Since the equilibrium calculations predict that Pb and Cd vaporize at above 973K, these results are due to Pb and Cd vaporization and subsequent reaction in the furnace and/or nucleation in the probe. The addition of 5 % dispersed kaolin power causes an approximate 51 % of Pb and 40 % Cd reduction in the fine particles at the temperature of 1223K during sewage sludge combustion. Pb compound in coarse particles becomes insoluble because of the reaction with kaolin in the furnace.

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Combustion of municipal sewage sludge was conducted in pilot plant incinerator for estimating heavy metal behavior in exhaust gas by using deposited particle on each chamber as indicator. Slag index, vaporization index, deposition index and fly ash index were identified to be indicator. The result indicated that most of volatile groups could volatile from sludge and As, Pb, Cu, Cd could remain in flue gas. The main deposited particle elements were Zn, P, S, Na, Fe, Al, Si, Ca. and the difference of them in each chamber was observed In secondary chamber, the main deposited particle was Fe but in other parts, the main deposited particle was Zn. At water cooling part, the maximum deposited particle composition is volatile group. From XRD analysis, the main chemical compounds were Zn₃(PO₄)₂, AlPO₄, FePO₄ and Fe(OH)₃. In addition, deposited particle sizes compared with fly ash particles were about 50 times larger size.

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In Taiwan, rice husks are plentiful agricultural waste. The rice husks are treated primarily as waste. Some rice husks are used such as organic manure, fodder, etc. From the energy point of view, rice-husks can be used as biomass fuel. In the recent years, tests were carried out to study the feasibility of recovering the heat energy from rice husk combustion. In this work the operating parameter effects on rice-husk combustion were investigated in a pilot scale vortexing fluidized bed combustor (VFBC).
The experiments were carried in a pilot scale VFBC, a 0.64m×0.32m rectangular combustion chamber constructed of freeboard with 0.45m inside diameter and 4.85m in height. The first-air flow rate, secondary-air flow rate, and bed temperature and the primary-air ratio (the ratio of primary air flow rate to the total air flow rate) were investigated.
The results of this study indicated that the combustion proportion in the bed increased with the primary air flow rate, but decreased with the bed temperature. The secondary-air flow rate had no effect on the combustion proportion in the bed. The combustion proportion above the secondary-air injection was largely influenced by the combustion proportion. In the in-bed oxygen rich condition, the combustion efficiency increased with the secondary-air flow rate, but decreased with primary-air flow rate and bed temperature. Therefore, lower temperature (600°C) combustion with a lower primary-air flow rate is recommended.

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Combustion of high fluoride content coal as an energy resource in China has caused serious fluoride pollution problem. It was reports in 1995 by the Agency for Prevention and Treatment of Endemic Diseases of China that fluorine poisoning caused by water and coal-burning touched 596 millions residents and there are 49 millions cases with dental fluorosis and with bone fluorosis. Fluorine poisoning is very difficult to cure. It is important to control of fluoride emissions during coal combustion.In this work, Ca(OH)₂ was used as defluorination agent to decrease fluoride emissions during coal combustion. When the molar equivalency of Ca to S equaled 2, the resulting defluorination efficiency of Ca(OH)₂ was 50% and deSO₂ efficiency was 63% at 900°C. Experimental results showed that defluorination efficiency increased with decreasing temperature. White-coal, made by coating the surface of a coal briquette with a thin layer of Ca(OH)₂, was tested as a new solid fuel. The result shows that the white-coal emits less fluorides and SO₂ in both volatile matter combustion and char combustion.

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In Asian countries, environmental destructions are progressing rapidly. For example, in Indonesia, forest of 1mil.ha is disappearing every year.¹⁾ In India, agricultural land of 5 mil.ha. has been salinized in the past²⁾. In China, , the desert area is increasing by 0.34 mil.ha/year³⁾. In this lecture, the main cause of environmental destruction in Asian countries is discussed at first and the way to the sustainable development of Asian countries is next. Sustainability here is defined as follows. "The present generation should hand over artificial and natural capitals those were succeeded from the former generation, where natural capitals mean rich soil, beautiful forest, wild creatures, clean air and waters, fossil fuels etc. those are non-renewable natural resources". Hence, Sustainable Development of Asian countries means "Economic growth of Asian countries keeping sustainability".

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Existence of sulfur compounds in coal limits its industrial application due to environmental as well as technical problems. In an extensive work, attempts have been made to desulfurize high sulfur Iranian coals for coke making for the steel industry. For this purpose, several physical, biotechnological and chemical methods for upgrading these coals before combustion are used. This paper attempts to demonstrate the potential of supercritical methanol/water and methanol/NaOH solvent mixtures for the removal of sulfur from an Iranian coal with total sulfur of 3.1%. Supercritical fluids have unique capability in enhancing the solubility of organic components. A batch reactor, 7 liters, equipped with an agitator was used in this study. The effect of methanol and caustic concentrations, reaction temperature and reaction time on removal of ash and sulfur, plastometry properties and recovery percent was investigated. The effect of each variable on the desulfurization of the coal was evaluated by measuring the sulfur content, the ash yield and the coal yield. Depending on the desulfurization conditions, the total sulfur reductions were varied from 7.45% to 30%. Desulfurization rate has been enhanced by increasing temperature and reaction time. It was found that sulfur removal increased with an increasing concentration of NaOH. In fact, NaOH can break the C-S bonding in coal, which enables greater penetration of methanol.

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Tabas high sulfur coal was desulfurized by leaching with sodium hydroxide solution in a batch reactor which was designed and built for this purpose. The effect of caustic concentration, coal particles, reaction temperature and reaction time on the removal of ash and sulfur was investigated. Depending on the desulfurization conditions, the rate of reduction for total, pyritic and organic sulfur was varied. Desulfurization rate has been enhanced by increasing temperature, sodium hydroxide concentration and reaction time. Also, plastometry properties, coal recovery percentage and ash removal, measured in this work, were found to be function of the above operating parameters. Finally, the rate of desulfurization reaction was found to be well represented by a continuous model that was second order with respect to pyritic sulfur.

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Ethyl acetate (EA), an important solvent used in petrochemical and polymer industries, is one of the toxic volatile organic compounds (VOCs). Though the toxicity of EA may not be so alarming, still it is also an environmental necessity to enquire after the techniques and processes for the removal or recovery of EA from air. Activated carbon is a good adsorbent because of its large surface area, which is result of its vast infrastructure of pores. The successful application of adsorption as an industrial separation technology requires intensive study of phenomena such as equilibria and the kinetics of adsorption, coupled with mathematical model that correctly describes the dynamics of fixed bed columns. In this paper adsorption equilibrium of EA has been studied experimentally in activated carbon at three different temperatures 30 °C, 45 °C, & 55 °C. The experimental equilibrium data were fitted with Freundlich and Langmuir isotherm models to obtain the suitability of the models, model parameters, saturation capacity, and heat of adsorption. Overall effective mass transfer coefficient of ethyl acetate adsorption on activated carbon has been evaluated using Uptake curve method. Results showed that the isotherms are of Brunauer type-I and are well fitted with Langmuir isotherm model. The overall effective mass transfer coefficient, k values don't show any distinct effect of flow rate on it leading to the conclusion that the pore diffusion is predominant. Heat of adsorption values both by van't Hoff equation and Clausius - Clapeyron equation are in the order of 10⁵ J/kg and overall effective mass transfer coefficient is in the order of 10^-4 s ^-1.

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Catalytic combustion of the volatile organic compounds (VOCs) has an advantage of low oxidation temperature, which leads to low energy consumption. It is widely applied into industry. A novel preparing technology of Pt/Al₂O₃/Al catalyst for VOCs' catalytic combustion was presented in this paper. Al₂O₃ film was formed on aluminum plate by anodic oxidation in oxalic acid solution at current density of 50 A/m². After the anodic oxidation, platinum was supported on the oxidized plate in aqueous solution of chloroplatinic acid hexahydrate via the electrolysis supporting method with alternating current in several minutes. Platinum loading of the developed catalysts was about 0.3 wt% and dispersion was about 50%. It indicated that platinum can be deposited on the anodized aluminum film. Through the respective combustion of benzene and toluene, activity of catalyst was evaluated. Above 90% conversion was obtained at 523 K in combustion system with space velocity of 20,000 h^-1and VOC concentration of 1000 ppm.
Comparison with the impregnation method was also carried out. The results indicated catalyst prepared by the electrolysis supporting method has higher activity than that prepared by the traditional impregnation method, although the former has a lower platinum loading. In this paper, reasons for this high activity were also discussed from platinum dispersion, surface characters and so on. It can be concluded that the electrolysis supporting method share advantages of short time, high-activity and no use of NH₃.

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Photocatalytic oxidation of 4-chlorophenol (4-CP) was investigated by using a multi-stage reactor system with titania immobilized on a stainless steel mesh under an irradiation of 11 W low pressure mercury lamp with the wave length of 200-300 nm. Catalytic activities of 4-chlorophenol degradation over Ag/TiO₂ (Degussa P25), Au/TiO₂ (Degussa P25) and temperature treated TiO₂ (Degussa P25) were studied in both the batch suspended and continuous immobilized systems. The presence of either temperature treated TiO₂, Ag/TiO₂ or Au/TiO₂ affects insignificantly the 4-CP degradation compared to the photolysis. In contrast, TiO₂ significantly affects the intermediates, hydroquinone and hydroxyhydroquinone. The presence of Ag and Au does not improve the catalytic activity of TiO₂ in the 4-CP degradation but it affects the degradation of intermediate products. The commercial TiO₂ was immobilized on the cylindrical stainless steel mesh by dip-coating with the suspension of TiO₂ (Degussa P25) in methanol and used as the catalyst in the multi-stage reactor unit. The titania on the stainless steel mesh support was found to be well adhered and its activity was still high after the regeneration.

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A cylindrical wetted-wall corona discharge reactor was used for removal of acetaldehyde from gas mixture of O₂ and N₂. The reactor consists of a wire cathode stretched along the axis of a cylindrical anode. The gas mixture was continuously fed through the reactor in one pass, whereas water was circulated as a falling thin film on the inner wall of the anode. Short-lived species such as ions and radicals as well as ozone are produced in the reactor by gas corona reactions. When some of these short-lived species drift and reach the water film, reactive OH radical is produced in the water. Gaseous acetaldehyde was mainly removed from gas stream by absorption, meanwhile absorbed acetaldehyde in water was decomposed by aqueous radical, OH, resulting in sustainable removal of acetaldehyde. Ozone oxidation did not significantly contribute to removal of acetaldehyde under the present condition and gaseous acetaldehyde was not effectively removed in absence of oxygen. When oxygen coexisted in gas mixture at 5%, acetaldehyde was removed effectively resulting in sustainable removal of acetaldehyde. However, an increase in oxygen concentration caused the decreasing removal extent when the corona current was excessively high. This is because corona-induced turbulence broadened the residence time distribution of gas in the reaction zone. Moreover, oxygen strongly influenced the decomposition of aqueous acetaldehyde and TOC in water. There were a minimum current and a maximum inlet concentration of gaseous acetaldehyde leading to steady state operation because aqueous acetaldehyde and TOC could be effectively decomposed. There was no significant by-product detected in treated gas.

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A number of techniques available for removing volatile organic compounds (VOCs) include adsorption, biofiltration and incineration. However, these techniques require further treatment and/or are energy-intensive leading to high treatment costs. Both plasma and photocatalysis are effective and economical alternatives since these two techniques can be operated in ambient conditions resulting in low energy consumption compared to the conventional methods. The main purpose of this work was to apply a combined plasma and photocatalytic system for VOC removal. A four-stage plasma and photocatalytic reactor system was set up to investigate the oxidation of benzene. An increase in either applied voltage or stage number of the plasma reactors enhanced both benzene conversion and CO₂ selectivity, which is in contrast with the effects of frequency and feed flow rate. The commercial TiO₂ (Degussa P25), sol-gel TiO₂, and 1%Pt/sol-gel TiO₂ were used as photocatalysts. The presence of all studied photocatalysts hardly affected the benzene conversion but increased markedly the CO₂ selectivity. The synergistic effect of photocatalysts presented in the plasma reactor resulted from the activation of TiO₂ by the energy generated from the plasma.

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Vacuum heating separation is one of the promising methods for removing insulation oil from used pole transformers. Using this method, insulation oil and PCBs are removed from the pole transformers by vaporizing under vacuum condition at the temperature of 200°C. The vacuum heating separation method has a high removal performance without pyrolyzing of insulation oil, PCBs and pole transformers. However this method requires a long treatment time to detoxify the pole transformers, because the pole transformers were heated by radiative heat transfer under vacuum condition. The purpose of this study is to make the vacuum heating separation method more efficient by using a vibration dryer. This new method was able to reduce not only the treatment time, but also running cost dramatically. From the experimental estimation, the heating time was shortened 48-50 % and the equipment space was saved 84-88 % in comparison with conventional plants. The fundamental performance of PCBs removal from various samples by the vacuum heating method was also investigated. As the result, PCBs was removed below the removal standard on the both copper and insulation paper, and PCBs concentration in the activated alumina was also reduced.

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The chlorine in PVC originates from sodium chloride separated by electrolysis consuming a large amount of electricity. On the other hand, about 1/2 of sodium chloride supplied to soda ash industry is used as a glass additive. To show the potential of utilizing waste PVC and waste glass that have been mainly landfilled, in the present work, it is experimentally demonstrated with a laboratory scale fixed bed reactor that all of the chlorine generated from PVC can be neutralized by sodium in waste glass particles forming NaCl in the range of 450-550°C. SEM and EDS studies confirmed the crystallized salt on the surface of glass particle after reaction. Chlorine content in any of gas, char and tar was lower than that for the blank tests performed without PVC indicating that they can be used as fuels with no corrosion nor the toxic organic halides formation. The formation of NaCl and fuel gas from waste PVC and waste glass makes it possible not only to recover energy that is supplied during separation of NaCl by electrolysis but also to close their nationwide material flow.

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The development of waste treatment technologies for various types of waste from different sectors is inevitable. The technology should protect the environment, valuable resources and should be economical. Synthetic polymeric materials are one of the major portions of wastes in the developed and developing countries. Feedstock recycling process appears to be most promising among the various other methods. Dehalogenation process is a key technology in feedstock recycling mixed halogenated waste plastics. In this study, two different approaches have been made to clarify the effectiveness of our proposed catalytic dehalogenation process using various iron oxides and calcium carbonate as catalyst/sorbent. The first approach (two step process) is (i) thermal decomposition of waste plastics into oil, which contains various halogenated compounds and (ii) develop dehalogenation catalysts for the catalytic dehydrochlorination of organic chlorine compounds from mixed plastic-derived oil in a fixed bed reactor. The second approach (single step process) is the simultaneous degradation and dehalogenation of chlorinated (PVC) and brominated (high impact polystyrene with brominated flame retardant - HIPS-Br) mixed plastics to produce halogen free liquid products. We report a catalytic/sorptive process for the dehalogenation of chlorinated and brominated organic compounds formed in the pyrolysis of PVC and HIPS-Br mixed waste plastics i.e., PE, PP, and PS. During dehydrohalogenation, the iron and calcium based catalysts were transformed into their corresponding halides, which also showed high activity for the dehydrohalogenation of the organic halogenated compounds. The presence of small quantity of poly ethylene terephalate (PET) in municipal waste plastics and waste from electric and electronic equipment (WEEE) had significant effect on the formation of degradation products and dehalogenation process. The developed iron oxide and calcium carbonate carbon composites were effectively removed the halogen content with bifunctional (catalytic/sorptive) activities. The halogen free plastic derived oil (PDO) can be used as a fuel oil or feedstock in refinery.

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