In Japan, the amount of plastic wastes is about 10 million tons per year and a part of them undergoes recycling processes such as melting/molding followed optionally by liquefaction, gasification, use as a reduction agent in blast furnaces, etc. In some other processes, the energy liberated by the incineration of the plastic wastes is recovered with high efficiency. Nevertheless, the other part of the plastic wastes is not suitable for such processes and is disposed by land filling or by simple incineration. Among the refractory plastics, PVC is especially difficult to treat and in Japan only about 400 thousand tons of PVC out of 1 million tons of PVC wastes are recycled every year, the remainder being disposed by land filling or incineration as stated above. However, when PVC is incinerated, hazardous compounds such as dioxins and HCl are liberated in the atmosphere, leading to a pressing requirement for new low cost safe disposal technologies. Accordingly, we are now intending to develop an advantageous process preventing the formation of such pollutants while recovering the enormous quantities of hydrogen present in PVC for a use as a clean energy source for, for instance, the fuel cells. In order to propose a rational solution, we gathered detailed statistics concerning the PVC production/use/disposal in Japan. We also examined and compared the existing and emerging PVC recycling technologies. Further, Na-containing wastes were considered inter alia as good candidates for a low cost HCl neutralization process, and subsequent qualitative/quantitative investigations were accordingly performed.

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Carbon dioxide reforming of methane, or dry reforming, is one of the alternative ways to produce synthesis gas. This reaction has many advantages over steam reforming. However, this reaction has an important problem that is carbon deposition on the catalysts. Much effort has been directed toward development of catalysts, which give high activity and stability. The purpose of this work is to study the effect of metal loading, adding promoters, and reaction temperature of carbon dioxide reforming of methane reaction over Ni supported on clinoptilolite, which is the most abundant natural zeolite. The promoter that was selected to be used is Ce. All of the catalysts were prepared by using incipient wetness impregnation method. The reaction was performed at 700°C. The results shown that at 700°C, 8wt%Ni/clinoptilolite gave the highest activity over 1wt%, 3wt%, 5wt%, 10wt%, and 15wt% Ni loading. It gave more than 60% conversion of CH₄ and CO₂ and also gave high hydrogen selectivity. After added promoters to 8wt%Ni/clinoptilolite, it was found that Ce could enhance both activity and stability of this catalyst. With 3wt%Zr the catalyst gave about 70% conversion of CH₄ and CO₂.

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This paper descries advanced low-temperature steam reforming of methane in plasma-catalyst hybrid reactor. Synergistic effect between Dielectric Barrier Discharge (DBD) and 3wt%Ni/SiO₂ catalyst was observed at lower reaction temperature (400°C-600°C). Methane conversion exceeded far beyond equilibrium conversion, while product selectivity tended to follow equilibrium composition at given conditions: energy cost and energy efficiency were improved by 134 MJ/kg_H₂ and 69%. According to numerical simulation of barrier discharge in pure methane, production of large number of vibrationally excited methane seems to contribute significant increase in methane conversion since vibrational species promoted dissociative chemisorption on nickel surface at lower temperature. Reaction mechanism is also discussed based on gas temperature measurement by emission spectroscopy of plasma reactor.

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Recently, the miniature fuel cells emerged as a promising power source for applications such as cellular phones, small digital devices, and autonomous sensors to embedded monitors or to micro-electro mechanical system (MEMS) devices. We designed micro-fuel processor system, which consists of a micro-reformer and fuel cell. Micro-fuel processor system generates H₂ rich gas from NaBH₄ solution. In our experiment, we have integrated micro-fuel processor system using low temperature co-fired ceramics (LTCC) process because LTCC is superior to other materials principally due to its high thermal and chemical stability, simpler fabrication processes, and lower materials cost. Therefore, we have studied and integrated micro-fuel processor system containing embedded heaters, cavities, membrane-electrode-assemblies (MEA), and 3D structures of micro-channel with LTCC. We developed the monolithic fuel cell system using LTCC process. Also we optimized the LTCC process.

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We studied steam reforming of ethanol at room temperature and atmospheric pressure using low energy pulse (LEP) discharge. In this study, we employed characteristic novel reformer, one electrode was made of carbon fibers (o.d. 7.0µm) bundle. So fuel was supplied to discharge region by capillary action of the fibers and reformed directly by LEP plasma without any pump or heater. When using this reformer, at first, the fuel was evaporated by heat emission from electrode, and then the vaporized reactants were reacted. Produced gaseous compounds were collected from upper part of the reactor, and analyzed by gas chromatography. H₂ and other compounds: CO, CH₄, CO₂, C₂H₄, and C₂H₆ were produced, and the formation rates were increased in proportion to the increase of the gap distance and input power. And compared to the former conventional reformer, the results were equivalent to the rates of gas phase reactor. The effects of ethanol concentration and of energy efficiency were studied, and the efficiency has reached 41.7 % at the ethanol concentration of 50 %, the discharge gap of 3.0 mm.

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Technical demonstration and commercialization of an innovative small-scale gasification and power generation system for solid fuels such as wastes and biomass are described which is known as the STAR-MEET system. In this system, a fixed-bed pyrolyzer combined with a high temperature reformer using a high temperature steam/air mixture is employed. From the experimental results using various solid fuels, it has been demonstrated that the injection of high temperature steam/air mixture into the pyrolysis gas effectively decomposes tar and soot components in the pyrolysis gas into CO and H₂, and almost dust and tar free clean reformed gas can be generated. This gasification system generates low BTU gas from solid fuels. Power generation experiments using a small, dual fueled (20% light oil gas + 80% low BTU gas) diesel engine demonstrated high thermal efficiency around 30% and low emission (especially NOx). Based on these R&D achievements, Ichiki-town located in Kyushu area of Japan has built a 20tons/day scale slagging MSW (Municipal Solid Waste) gasifier combined with 900kW dual-fueled diesel engines and its trial operation began from February, 2004. This paper also describes the outline of this plant and start-up data which were obtained during trial operations. Finally, an innovative small-scale hydrogen generation system from solid fuels called as the HyPR-MEET system is proposed. This system is based on the high temperature steam gasification process and some fundamental experimental results are shown which demonstrate the technical feasibility of the HyPR-MEET system.

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Thermo-chemical conversion of wood biomass at low temperatures and aqueous conditions were performed using an autoclave. Hydrothermal treatment of wood biomass for the production of oxygenated hydrocarbons with various reaction conditions were carried out and optimized the reaction parameters for the high oil yields. Environmentally benign separation and analysis process applied for the identification of compounds at different stages to understand the nature of products. With low reaction temperatures, (180°C-250°C) high reaction times (60 min) are favored for high oil yields, and conversely at high reaction temperatures, low reaction times (15 min) favored. The use of base catalysts improved the conversion of biomass and subsequently high oil yields were observed. Under the optimized reaction temperature and time, the effect of various alkaline (Na and K) hydroxides and carbonates were investigated. In addition, the biomass components such as cellulose, lignin was also used for the hydrothermal treatment and compared the composition of oil products. Oil products were extracted from both liquid and solid portion of reaction products by different solvents and analyzed them individually. The use of alkaline hydroxides and carbonates had significant effect on products yield and composition of oil products. Catalytic hydrothermal treatment of biomass produced mainly phenolic compounds, benzenediol derivatives and the quantity of these compounds were changed depending on type of base solution. Compared to thermal run, the use of base solutions hindered the formation of char and favored the formation of oil. The volatility distribution of hydrocarbons were characterized by using C-NP gram ( C stands for carbon number and NP stands for normal paraffin) and it showed that the majority of hydrocarbons for all runs including thermal were distributed at the boiling point rage of n-C₁₁ (174 to 198°C). The products from hydrothermal treatment of sawdust were analyzed using gas chromatograph equipped with mass selective detector (GC-MS), thermal conductivity detector (GC-TCD), ¹H, ¹³C nuclear magnetic resonance (NMR), total organic carbon content (TOC) and ion chromatograph.

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A new kinetic model was developed for the pyrolysis of cellulose. To precisely describe the pyrolysis behavior, it is necessary to take into account of the change in cellulose macromolecule structure during pyrolysis. The kinetic parameters of dehydration and devolatilization reactions were represented as a function of the crystallinity or the amount of the hydroxyl groups. The estimated activation energies were spread over 110-210 kJ/mol with the crystallinities. The validity of the presented model was examined through the model calculations. The weight loss curves were strictly calculated for any heating rates by using the presented model. Thus, the proposed model could successfully describe the change in the structure of cellulose during pyrolysis.

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Volatilization of alkali and alkaline earth metallic (AAEM) species during pyrolysis of pulverized biomass was investigated. Pine sawdust and sugarcane bagasse were pyrolyzed in a wire-mesh reactor, in which the secondary reactions of nascent volatiles were successfully minimized in the gas phase and over the surface of nascent char by forcing flow of He to pass through the monolayer of biomass particles being heated at a rate of 1 or 1000 K s^-1 up to peak temperature of 573-1173 K. Upon heating the sawdust, AAEM species were released from the nascent char after completion of Cl release and evolution of tar and lighter volatiles. While heated at 1000 K s^-1 from 823 up to 1173 K, the nascent char released Ca and Mg as extensively as K and Na with their losses of 20-25%. Release of AAEM species continued during further heating at 1173 K, which caused total losses of K and Na over 99% while those of Ca and Mg as high as 40-60% within a period of 100 s. In contrast to these results, no significant release of AAEM species were allowed during the pyrolysis in a fixed-bed reactor, in which no forced flow of the carrier gas was available through the fixed-bed of char particles. Repeated release of AAEM species and their readsorption onto the char surface thus suppressed or even inhibited the net volatilization. Based on the combined effects of the heating rate, peak temperature and holding time at the peak temperature, it was concluded that AAEM species were released from the char mainly as elemental species rather than hydroxides and chlorides.

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Emission of particulate matters having diameter of 10.0µm and less, PM10, was investigated in a laboratory-scaled combustion of dried sewage sludge. Influences of the combustion parameters were identified including both temperature and oxygen content in the gas atmosphere. The reaction temperature was fixed at 1200°C, whereas the oxygen content was from 10, 30 to 50% in the gas atmosphere. PM₁₀ was collected by low-pressure-impactor. Each size of it was subjected to characterization by several techniques including XRF, SEM-EDX and CCSEM for the chemical speciation. The results show that, the content of ash in the raw sludge affected its PM₁₀ concentration positively. About 0.1wt% of the inherent inorganic metals directly transferred into PM having size larger than 2.5µm, they mainly are of the refractory metals. On the other hand, about 0.4 4.0wt% of the inherent inorganic metals vaporized and condensed into the ultrafine particulates having size less than 0.5µm, they mainly are of the heavy metals including Zn, Mn, Pb, Cu, etc. A portion of the vaporized metals agglomerated with the refractory elements to form particulates having size ranging from 0.5 to 2.5µm. In addition, PM emission was improved exponentially with the increasing of the oxygen content in the gas atmosphere. Finally, the thermodynamic equilibrium calculation proved the vaporization of heavy metals within sludge and their re-condensation and chemical reaction with the other species in the gas atmosphere. The results were consistent with CCSEM characterization on PM.

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Development of chemical heat pumps and dry sorption systems using solid-gas thermochemical reactors requires determining their optimal operating conditions. Many previous studies particularly noted that the performance of solid-gas thermochemical reaction would be reduced due to low heat transfer rate in the reaction beds. In this study, enhancement of effective thermal conductivity of reaction beds was therefore studied using magnesium oxide/water reaction, which was expected to be utilized for chemical thermal storage in a cogeneration system. High thermal conductive carbon fiber was installed into a reaction bed as a brush in order to be dispersed in the whole reaction bed and improve the effective thermal conductivity. In addition to the experiment, a two-dimensional mathematical model describing heat and mass transfer as well as chemical reaction rate was formulated and solved for its evaluation. Numerical results indicated that increasing the effective thermal conductivity essentially promoted the magnesium oxide/water chemical reaction rate. Qualitative agreement between experimental and theoretical results was obtained. Moreover, optimum operating conditions for a solid-gas thermochemical reactor were also discussed according to the results obtained in this study.

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An experimental study has been conducted on the structural properties of reactor beds packed with CaCl₂ reactive salt particles with a view of evaluating the heat transfer mechanism in porous particle beds. Particulate and bed properties of CaCl₂ reactive particles, which are CaCl₂/CH₃OH, CaCl₂/CH₃NH₂ and CaCl₂/NH₃ reactive salts applicable to driving chemical heat pumps, have been studied by means of mercury porosimetry and SEM as well as bed volume measurements. From the porosimetry measurements, it was found that the void fraction inside particles of CaCl₂/CH₃OH salt varied from 0.2 to 0.6 with increasing the moles of methanol reacted with CaCl₂, while the void fraction outside particles was kept almost constant during reaction cycles. Based on the experimental results of CaCl₂/CH₃OH particles, the void fraction inside particles was estimated, varying from 0 to 0.8 in CaCl₂/CH₃NH₂ and from 0.3 to 0.7 in CaCl₂/NH₃ particles. SEM observations revealed that after several reaction cycles a drastic change took place in pellet structure; the shape and the state of aggregation of the grains in a pellet had changed to completely different ones from those of the original unreacted CaCl₂. Such changes in grain and pellet structures may cause the considerable decrease in the thermal conductivity of these reactive salts observed in our previous study.

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Cyclic reaction performances of solid reactants for a CaO-CO₂ chemical heat-pump designed for upgrading and storing high-temperature thermal energy were studied. It was observed that solid reactants prepared using CaCO₃ particles have micro-order pore structure among the particles and nano-order pore structure in the particles. With the proposed model, which is considered the pore structure change during reactions, the numerical analysis suggested that the carbonation and decarbonation rates were determined by micro- and nano- order pore structure changes, respectively. Upon experiments of CaO carbonation and CaCO₃ decarbonation at 923K, the pore volume change correspond to the greater part of the total volume change during decarbonation was observed in the range from 10 to 30 nm of pore radius.

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Adsorption heat pump (AHP) system has a big advantage in generating cold heat energy below 283 K for air conditioning by utilizing low temperature thermal energy below 353 K which is enormously discharged into atmosphere as waste heat. However, AHP system has a critical problem of low heat output density per unit adsorber volume, and so a commercial AHP system is 4 times or over as big apparatus volume as an absorption heat pump. In this paper, we have proposed new high-performance plate fin-tube type module (FT module) for downsizing the AHP by improving heat and mass transfer in the adsorber. We have also carried out experimental study on cold heat output performance of the module with a lab-scale apparatus. It is found that the AHP system incorporated with the FT module could operate by using heat source of around 333 to 353 K, and the heat output increases with increasing regeneration temperature and velocity of heat exchanging fluid. It is also demonstrated that the AHP system with plate fin-tube type module achieves more than 1.3 times heat output performance per unit adsorber volume as much as that with the previous circular fin tube module (FST module).

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In this paper the applicability of a novel activated carbon/methanol pair to an adsorption refrigerator was discussed on the basis of its adsorption characteristics. Adsorption equilibria of methanol vapor on an activated carbon fiber with high apparent density (HD-ACF), which was prepared from phenol resin fibers without any binders by a hot briquetting method, were newly measured at 30 to 80 °C by using a magnetic suspension balance (MSB). The cooling effects in an ideal cycle of the adsorption refrigerator were estimated under the realistic operating temperature conditions from the q-P-T diagram obtained. The results showed that the cooling effect estimated for the HD-ACF/methanol pair was significantly affected by the evaporation and regeneration temperatures, and its value was greater than those for the commercial activated carbon/methanol pairs. Furthermore, we carried out experiments on continuous repetitions of adsorption and desorption for this working pair using the MSB apparatus. During eleven repetitions similar adsorption behaviors were observed, and the difference between the maximum and minimum values of the amount adsorbed remained stable. The results obtained indicated the potentials of the HD-ACF/methanol pair for the application to compact adsorption refrigerators.

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This paper provide hybrid modeling of economics and engineering approaches and tests the hypothesis that technological change has offset resource depletion for offshore oil and gas production using a unique micro-level data set from 1947-2000. The study supports the hypothesis that technological progress has mitigated depletion effects for our case study, but the pattern differs from the conventional wisdom for non-renewable resource industries. Contrary to the usual assumptions of monotonic changes in productivity or an inverted “U” shaped pattern, we found that productivity declined for the first 30 years of our study period. But more recently, the rapid pace of technological change has outpaced depletion and productivity has increased rapidly, particularly in most recent 5 years of our study period. We also provide a more thorough understanding of different components of technological change and depletion. Sound energy and environmental policies require reliable forecasts of production and pollution, as well as supply response to policy actions. In this study, we describe a model for forecasting long-term production and pollution in the offshore oil and gas industry in the Gulf of Mexico under different scenarios. A model based on disaggregated field-level data is used to forecast production and pollution through the year 2050. The time path for resource depletion is determined as the net effect of technological progress and depletion under alternative scenarios for new discoveries. We also quantify potential efficiencies that could result from changing the design of regulations from the current command-and-control regime, to an approach that allows more flexible means of achieving the same environmental goals.

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The ease and thus mode of dewatering for a given material is highly dependent on the material's physical and chemical properties. For example, in lignite, which has in the order of 60% water, a significant proportion of the water is contained within the porous lignite structure, thus making lignite difficult to dewater. To express the water from the lignite, elevated temperatures and pressures are required. The CRC for Clean Power from Lignite is investigating Mechanical Thermal Expression (MTE) as a process with the potential to economically dewater lignite. In the MTE process, the lignite is mechanically pressed at moderate temperature (150-200°C) and held at sufficient pressure to ensure that the water is expressed from the lignite matrix as a liquid. The upgraded product can be used to increase the efficiency of existing power plants, or alternatively can be used as the feed to advanced technology generating processes which enable more efficient power generation with significantly reduced greenhouse gas emissions. Analogous to lignite, materials including biosolids (from sewage sludge) and bagasse (sugar cane waste) are notorious for being difficult to dewater, with conventional dewatering methods producing cakes with high moisture contents. The major focus of this paper is therefore to investigate the dewatering of a range of 'difficult to dewater' materials using MTE. Testing is completed in a laboratory scale compression cell at a range of processing temperatures (20-200°C) and compressive pressures (3-12MPa). It is illustrated that MTE is adaptable to a range of materials, with the moisture reduction significantly enhanced relative to conventional dewatering methods.

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When mineral matters in coal transform during the reaction, the ash compositions as well as the particle size distribution vary. This phenomenon affects fundamental characteristics of ash deposition. In the experiment, three types of coal with the different melting temperature and ash content were burned under the condition of high-temperature air pulverized coal reaction. A water-cooled tube was inserted into the furnace to make the ash adhere. Particle size and composition distributions of ash particles in both reacting coal particles and depositing layer were analyzed, using a Computer Controlled Scanning Microscope (CCSEM). As a result, quantity of the ash deposition on the tube surface increases with a decrease of the melting temperature of coal ash. The growth rate for the coal with low ash-melting temperature became higher. For structure of the deposit layer, fine particles of size less than 3 mm mainly consisted of the initial layer for three types of coal, and the thickness was about 30 mm. Deposition of fine particulates of about 3 mm became a trigger of initial deposition at the stagnation point of tube even if the different types of coal were burned. This phenomenon was also simulated by a simple deposition model, which considered turbulence of flow field, thermophoresis force to the ash particles and so forth. The chemical compositions of ash particles in the reacting particles differed from those in the initial deposition layer. This suggests that the chemical compositions also contribute to the ash deposition phenomena.

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A comparison of experimental data for the final moisture content and gas temperature profile for a pressurised entrained flash drier to a one-dimensional mathematical model developed previously for the brown coal mill process is discussed. A combustor fired with diesel and air was used to produce a flue gas at 800°C and 10 bara to flash dry Yallourn lignite at a nominal feed rate of 750 kg/hr. The comparison between model predictions and measured temperature profiles for the flue gas and final moisture content of the dried coal product showed excellent agreement. A new coal feeder arrangement was developed which provides a simple positive feeding device for feeding against a back pressure. The feeder takes as an input coal which is nominally < 50 mm and discharges it as a finely divided product with a mean particle size of approximately 1.0 mm. Coal moisture was reduced from 67 wt % to between 30 and 40 wt %.

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In order to examine the influence of the coal-included minerals on the CO₂ sorption characteristics of Ca-based sorbents during hydrogen production through sorption-enhanced coal gasification (HyPr-RING process) pulverized bituminous coal (Taiheiyo coal) samples with diameter ranges of 38-75 µm and 180-250 µm were gasified with high-pressure steam in the presence of Ca-based CO₂ sorbents at 873 and 973 K and at holding times ranging from 0 to 120 min in a laboratory-scale fixed-bed reactor. Local scanning electron microscopy-energy-dispersive X-ray analysis of the solid residues obtained under different conditions showed that some constituents of the coal-included minerals, such as Si and Al, were involved in the sorbent particles. The solid-solid reaction between the Ca-based sorbents and coal-included minerals became significant at the higher temperature and at longer residence time, which causes substantial decrease the CO₂-sorption ability of the sorbents. However, when a holding time of less than 10 min was employed, the solid-solid reaction between the minerals and the sorbents seemed to be suppressed, even at 973 K, because the rate of formation of inorganic compounds through the solid-solid reaction was not fast. Our results indicate that the holding time of the feedstock in the reactor should be shortened to avoid deactivation of the Ca-based sorbents during high-pressure steam gasification.

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Experiments have been conducted to obtain the optimum condition of steam drying process to produce upgraded coals with low moisture content. An Indonesian low rank coal, Berau coal, which has high moisture content and sulfur content of 20.02% in air dried basis (adb) and 3.09% in dry basis (db) respectively, was upgraded for 15 - 75 minutes in an autoclave at 200 °C, and at 175 - 275 °C for 60 minutes. Both of raw and upgraded coals have been analyzed to give moisture and sulfur content for the evaluation of the optimum condition of process. The result indicates that the moisture content is significantly decreased become 5.16% in adb at temperature of 275 °C for 60 minutes. On the contrary, the sulfur content was not significantly decreased.

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Plastic bags are greatly involved in modern lifestyle, especially in food and goods packaging, creating environmental concerns on waste treatment due to their low biodegrability. A large number of plastic bags with other municipal wastes are landfilled and burned into atmosphere. Pyrolysis of these plastics is an alternative for utilizing plastic waste because it can produce valuable raw materials that can be used in petroleum and petrochemical industries. Due to high energy consumption, catalysts are also employed in plastic pyrolysis to reduce costs of operation. The pyrolysis of commercial polypropylene film was studied in a semi-batch reactor. The reaction was carried out at 500°C for 1 hour under nitrogen flow. Sulfated zirconia was employed as a catalyst. The result showed that the cracking activity increased with the catalyst to polymer ratio and the amount of sulfate loading. Liquid product was the most dominant pyrolyzed product. Moreover, the addition of catalysts resulted in gasoline production, and the acidity caused higher kerosene and gas oil production.

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Almost all of the natural rubber produced nowadays is used for production of tires. Due to the longevity of rubber products, the disposal of waste tires has caused many environmental and hygiene concerns. Since there is an enormous amount of waste tire generated globally each year, reuse and recycling of the waste tires are becoming an important environmental issue. Pyrolysis is a recycling method for fully decomposing waste tires into various reusable substances. In the present contribution, catalytic cracking of waste passenger tires was investigated using ZrO₂/SO₄^2- as catalyst in a semi-batch reactor at 500°C under inert atmosphere. Gas products were found to be composed of methane, ethylene, ethane, propylene, propane, C₄-, C₅-, C₆-, C₇-, and C₈- hydrocarbons. The volume of liquid yield increased while gas and solid residue yield decreased with increasing loaded sulfate of up to 8%. Four different catalysts to tire ratios were tested (i.e. 0.1:1, 0.25:1, 0.5:1, and 1.0:1 w/w) for a fixed loaded sulfate of 4%. At 25% catalytic loading, the relative amount of light fractions was found to be the highest, which was found to be the optimal condition for pyrolytic recycling of the model tires.

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A fundamental study on biomass decomposition was carried out using a batch reactor at 973 to 1223 K under atmospheric pressure of nitrogen. In order to investigate the decomposition-enhancement effect of nano-porous inorganic materials on decomposition behaviors of a typical woody biomass material of Yakushima (Japanese cedar of Yakushima) systematically, thermal decomposition experiments were carried out in the presence of a variety of nano-porous inorganic materials using the batch reactor. The results showed that average pore diameter of the materials have a significant effect on the gas yield from biomass. The larger the pore size, the higher the gas yield. The gas yield from Japanese cedar was 14 wt% at 1223 K in the absence of nano-porous material. At the same temperature, the yield increased to 47 wt% in the presence of a silica having the maximum pore diameter (100 nm). This enhancement is thought to be due to further decomposition of tar vapor in the pores to gas. The final purpose of this research is to design and construct a test-scale continuous gasifier for fuel gas production from biomass.

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The authors investigated in-situ steam reforming of tar produced from rapid pyrolysis of biomass using a novel two-stage reactor. Pulverized biomass was continuously fed into the rapid pyrolysis zone of the reactor at 773 K, where nascent volatiles and char were isolated from each other. The volatiles were then mixed with steam and introduced into the steam-reforming zone at 873 to 1073 K consisting of a fixed-bed of mesoporous alumina particles. The yield of tar heavier than naphthalene decreased as the amount of volatiles fed into the fixed-bed increased, and finally reached an undetectable level (<<0.01% on a biomass carbon basis), leaving benzene and naphthalene with yields of 0.5 - 1% and below 0.05%, respectively. Coke was deposited over the alumina particles with a yield of 10 - 20%, and it acted as a catalyst active enough to eliminate polyaromatic hydrocarbons as the representative constituents of the heavy tar. Thus the mesoporous alumina played a dual role of eliminating tar and controlling the total yield of char and coke, and would therefore be suitable as the bed material for biomass gasification in two-stage fluidized-bed gasifier with the bed material being circulated between the biomass pyrolysis/steam-reforming zone and the char/coke combustion zone.

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A novel conversion process of PVC, that is, the production method of Cl-free high BTU gas via pyrolysis/gasification of waste plastics including PVC using Ca compound was proposed. In this process, waste plastics including PVC are pyrolyzed/gasifed with calcium compounds. The heat of reaction produced by the hydration and carbonization of calcium compounds is used to heat the sample up to the pyrolysis and gasification temperatures. It is not necessary to feed air or oxygen to provide a partial combustion. As the results, high BTU product gas is produced. A part of calcium compound is reacted with HCl emitted from PVC. In this study, the pyrolysis behavior of PVC was investigated in thermo-balance. The pyrolysis profile depended on the heating rate, slightly on the degree of polymerization and strongly on the metals included in the resin. The reactivity of Ca compound to HCl gas depended on the heat treatment temperature and the particle size. The gasification rate of the residue from the pyrolysis of PVC resin was affected by the metals included in the PVC resin. PVC can be decomposed by the heat of reaction produced via hydration and carbonization of calcium compounds. HCl emitted during pyrolysis of PVC was almost completely captured by Ca compound mixed.

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Electrochemical properties of iron carbide (Fe₃C) for an anode of alkaline battery and the effects of the electrode voidage on the performance of the battery were investigated. Cyclic voltammetry and charge-discharge measurements showed that the oxidization process of Fe₃C is different from that of pure iron, but it is irreversible. In charge-discharge cycles, discharge characteristics of Fe₃C became like those of pure iron, and the particles were pulverized to be smaller than 100 nm in diameter. By comparing of the discharge curves of electrodes with various value of voidage, it was found that the lower the voidage of the electrode was, the more specific capacity increased, up to as much as 450 mAh/g. In addition a maximum of the discharge potential appears at the voidage of 60%. Results of AC-impedance spectroscopy (ACIS) showed that the effective value of reaction surface area increased with the voidage to reach a maximum at the voidage of 60%. The opposite effects of voidage on the contact resistance between electrode particles and the diffusion resistance of electrolyte in the three-dimensional electrode were balanced to exhibit best electrode performance at the voidage of 60%.

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Ionic liquids (ILs), or molten salts, have received much attention from the areas of electrolytes of fuel cells and batteries. Their special properties such as wide electrochemical window, high conductivity, and wide operation temperature range make ILs attractive to electrolyte applications. For that purpose, new families of salts based on morpholinium organic cations combined with the bis(trifluoromethane sulfonyl)imide anions are reported in the present study. Morpholinium cation - based ILs' potential uses as electrolytes based on following some reasons: The effect of oxygen group in the cation for ionic conductivity, the advantages of synthesis and purification processes and cost reduction in production of imidazolium ionic liquids. These new pure ILs were proven to be conductive and, thermally and electrochemically stable(3 to 4.5 V). The conductivity values from 10^-3 to 10^-2 order are investigated in the temperature range between 20 to 50°C and they are also stable below the temperature at least 400 °C. Lithium-doped ionic liquids were also proven to be highly conductive and electrically stable. In addition, the physical and electrochemical characteristics of these Ionic liquids based on N-alkyl-N-methylmorpholinium salts have been investigated for their uses as electrolytes.

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This paper describes heat transport from higher to lower positions using a top-heat-type two-phase loop thermosyphon with an electromagnetic switching valve. The objective of this study is to develop the heat transport device which transports large amount of heat with consuming external electric power as small as possible. In the previous report, the operation principle was explained and it was shown that this heat transport device had the probability of a practical use. Also, the temperature and pressure variations at main points of the apparatus, and the heat transport efficiency were shown. In this report, the reliable operation of this device is reconfirmed and the temperature differences between the evaporator and the cooling water are shown by changing the heat input and the cooling water temperature using water and ethanol as the working fluids.

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This work describes a procedure based on a mixed template of copolymer F127 (poly(ethylene oxide)₁₀₆-poly(propylene oxide)₇₀-poly(ethylene oxide)₁₀₆) and surfactant CTAB (cetyltrimethylammonium Bromide) for generating nanocrystals of anatase TiO₂. The mixed template allows access to larger surface area, smaller size and higher crystallinity TiO₂ particles in comparison with single template. XRD and TEM show the TiO₂ nanocrystals have high crystallinity with the size of 3-5 nm which carry out obvious quantum confinement effect and high photocatalytic activity. The mixed template allows to make crack-free porous TiO₂ film with various thickness by repetitive coating and calcinations. Over 8% conversion efficiency of light-to-electricity with the TiO₂ film electrode has been obtained.

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Zeolites consist of alumina-silica structures of nano-sized cavities with different sizes and arrangement. In recent years, numerous studies have been conducted on the capability of zeolites as adsorbents in adsorptive gas storage (ANG) and gas separation. The adsorptive properties of zeolites depend on their structure, size, charge and distribution of cations. The effect of polyvalent cations on adsorption capacity of zeolites has been reported in the literature, which indicated that the adsorptive capacity increases with increasing charge density of the cation. The effects of metal balancing cation in zeolite structure on gas adsorption depend primarily on the size and shape of the gas molecule, the size of the cation and its location in the channel, and its interaction with the gas molecule. Zeolite modification such as cation-exchanged technique was used to determine the effect of different cation on gas adsorption characteristics. In this study, sodium cations originally present in zeolites are exchanged with other metal cations. It is observed that at very low concentration of adsorbed gas, the type of cation influences the adsorption characteristics, where divalent cations adsorb more gas than monovalent cations exchanged zeolite. At higher concentrations of adsorbed gas, the effect of cation is insignificant. However, different gases adsorb differently depending on the adsorbate-adsorbent interactions.

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Gas separation plant was studied for energy analysis because it consumed high energy. This plant consists of three main distillation columns (demethanizer ,deethanizer and depropanizer ) and ten heat exchangers. First of all, the process values, are needed to be measured and collected. The simulation used for this research because there were not enough measured data to apply energy saving technique. The commercial software, Aspen Plus, was used to figure out the unmeasured values. Grand Composite Curve (GCC) and Column Grand Composite Curve (CGCC) were plotted in order to study the integration between the columns and the process. To modify the process, retrofit techniques such as inspection and integration were presented. Three alternatives were proposed and the results showed that the largest energy saving (alternative number three) was 26.14 % of total energy consumption. This alternative was done by adding side reboiler at the deethanizer column which used hot stream as the background process to recover the heat. The consequent results would be energy saving on both the cooling tower load and the main reboiler duty of the deethanizer column. The process modifications were based on the possibility of changing existing plant. Data reconciliation is the technique for ensuring the reliability of measurement. This plant contained 20 measured and 170 unmeasured variables. Based on the energy and material balance, 30 reconciled variables were given.

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In the situation of high prices and depletion of the world energy, one way for energy management is in process integration. In Specific, pinch technology has demonstrated that good process integration pays off through simplicity of plant design and good use of energy and capital. The principle is to predict what should be achieved (targeting), and to then set out to achieve it (design). For modification of existing plants, the retrofitting is used with the same thermodynamic principles that underlie established pinch technology. This study uses the process data of Reformer area of an aromatics plant, which is reconciled coupled with the Pinch technology for retrofitting the heat exchanger network to obtain the best design which results in high degree of energy recovery. In this area of plant, nine heat exchangers can be found. The streams that involve in this pinch analysis can be grouped in two types; hot streams and cold streams, which are twenty four hot streams and sixteen cold streams. First of all, the target of energy saving will be conducted for the specified payback period. In this step the Problem table Analysis and composite curves have been done in order to find the area and energy target. The result of these targets show the very low payback period. The retrofit procedure then can be done by constructing the grid diagram and finding the heat exchangers crossing pinch point. Eliminating these exchangers plus adding some area of heat exchangers result in energy saving about 10-20%.

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This paper describes a new system combining fossil fuel with sustainable energy to produce liquid fuel like methanol with CO₂ zero emission process. In this system, the heat required for endothermic reaction is supplied from the sustainable energy such as hydraulic-, solar-, or wind-generated power. Preheating technology of coal-water mixture (CWM) is the core technology to realize the process, because sustainable energy is used as vaporization of water and decreases oxygen consumption in the gasifiers. Water in CWM was continuously vaporized with a preheater and steam and dry coal fine particles were atomized in a tube and fed to the pressure vessel or the combustion chamber, using experimental unit with a capacity of 2 ton/day-coal. The internal autothermal steam reforming of methane is also the core technology to avoid CO₂ emission. The new reactor consists of packed layers with oxidation and reforming catalysts. The bench-scale test with feed flow rates of 1 Nm³/h was conducted to gather process design data.

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Crude fractionation units are designed to separate the crude in several product streams (naphtha, gas oil, diesel, etc.). Crude fractionation is a highly energy intensive process and represented one of the most important areas for energy integration in a refinery by modifying the existing plants and generating improved designs. Important heat exchange also takes place, and the energy efficiency is related to the column design parameters. First, the optimal condenser and pump-around duties were determined for three types of crudes; light, intermediate, and heavy crudes with using the heat demand-supply diagram, an important tool for modification. These crudes constitute the targets for the design of a multipurpose heat exchanger network. The multipurpose design problem for which several alternative solutions of similar cost exist. Such property is suspected to be true for the retrofit case, that is several retrofit scenarios aimed at improving energy efficiency and/or throughput can exist and be competitive. The result was observed that when the optimal condenser and pump-around duties were located in these designs, the energy consumption and operating costs were reduced.

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Some supercritical fluids are able to replace toxic industrial solvents. So, from an industrial point of view, supercritical fluids are widely used in many fields such as pharmacy, food industry and environment. From a scientific point of view, the main interest of supercritical fluids is connected to the possibility to adjust continuously the physicochemical properties of these reactive media, such as selectivity, solvation, solubility or reactivity. In this paper, we present recent work on processes using supercritical media for processing materials related to fine particle synthesis and porous materials synthesis.

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L-poly(lactic acid)(PLA) microspheres have been produced by particles from gas saturated solutions(PGSS). A CO₂ saturated polymer solution containing ethanol is sprayed through a nozzle to air and/or aqueous solution. In this work, to control the particle morphology, the gas saturated polymer solution is expanded through the nozzle to water. After sprayed through a nozzle to air, polymeric fibers and coalescence particles were obtained. On the other hand, polymeric microspheres were obtained after sprayed through a nozzle to water. The particles were smaller than those produced by PGSS into air. Dispersion of polymeric particles in water impedes particles growth and agglomeration. The particles do not tend to agglomerate after expansion, since the ethanol used as cosolvent on the surface of particles diffuse through the water. The changing the pre-expansion pressure, nozzle diameter, and injection distance between the nozzle and water interface, controls the particle size distribution and morphology of microparticles.

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The rapid expansion of supercritical solutions (RESS) is well known as an effective method to manufacture fine particles as long as the target substances can be dissolved in supercritical CO₂. A potential for preparation of pharmaceutical microcapsules by RESS was investigated in this study. As an example, loperamide hydrochloride and N-Lauroylsarcosine were utilized as the kernel and coating materials, respectively. The drugs were dissolved in small amount of ethanol and chloroform before they were loaded into the supercritical CO₂. The experiments showed that the formation of fine particles of loperamide hydrochloride coated with N-Lauroylsarcosine could be completed in a single step by spraying the supercritical solution from 10-20MPa to atmospheric pressure through a 200 µm orifice. The coating effects were observed by a scanning electron microscope. It is found that ratio of the two starting materials greatly affects the final form of products. By optimizing the process parameters, microcapsules have been produced. The typical microcapsules consist of the kernel particle of about 4µm diameter with the coating layer of 1-2 µm thickness. The experimental result indicates that the rapid expansion of supercritical solutions can be a possible way for synthesis of composite microparticles of drugs.

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Polymer porous medium is used as an ion exchange resin, a supported reagents etc.. Recently, it is also considered for use as a supporting structure for cell cultures. In order to use polymer porous medium for these purposes, the surface area and 3-dimensional form are important. The polymer porous medium is usually made by suspension polymerization. However, with this method, it is difficult to control the surface area and 3-dimensional form. It is also difficult to remove the water from the porous medium and expensive to treat the resulting waste water. We examined a method of producing the polymer porous medium using supercritical carbon dioxide as a solvent. The styrene and divinylbenzene (DVB) were cross-linked polymerized, and a porous medium was generated in the supercritical carbon dioxide. The polymerization rate and the properties of the form of the porous medium were investigated under varying conditions. As a result, it was found that the polymerization rate was fast under a low polymerization pressure and at a high DVB concentration, while the surface area of the porous medium was large at the high concentrations of the initiator and DVB. This large surface area was due to the fact that the primary particles in the porous medium were small under high pressure, and there was little coalescence of the primary particles at the high DVB concentration. In this study, it was shown that the 3-dimensional form of the porous medium can be quantitatively controlled by varying polymerization pressure, DVB concentration, and so on.

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The kinetics of polyethylene terephthalate (PET) depolymerization in supercritical methanol was investigated to develop a chemical recycling process for post-consumer PET bottles. PET with a high molecular weight of IV 0.84 was depolymerized in a batch reactor at temperatures between 553 and 593 K under estimated pressures of 13 - 15 MPa. In addition to PET with high molecular weight, PET with low molecular weight, such as its oligomer, bis-hydroxyethyl terephthalate (BHET) and methyl-(2-hydroxyethyl) terephthalate (MHET) was used as a model reactant to clarify the depolymerization scheme of polyethylene terephthalate in supercritical methanol. The reaction products were analyzed with size exclusion chromatography, high performance liquid chromatography, and high performance liquid chromatography-mass spectrometry. The main products of each reaction were the monomers, dimethyl terephthalate (DMT) and ethylene glycol (EG). The depolymerization of high molecular weight PET to its oligomer was faster than that of oligomer to its monomer. PET was depolymerized into DMT and EG through MHET. The molecular-weight distribution showed that the depolymerization of PET proceed consecutively where the step of the oligomer to its monomer would be a rate-determining step. MHET is a relatively stable intermediate in the depolymerization. The rate constants were estimated with simple reaction models.

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Decomposition of toxic substances such as dioxins and PCBs is an urgent environmental issue. Dioxins are present in envionmental matrices such as incinerator fly ash and contaminated soil. Since PCBs were used in large quantities as insulation oil in transformers and other applications, a large number of equipment and devices containing PCBs still exist. Solid materials containg dioxins and PCBs must be properly ptreated in additon to liquid materials. Supercritical fluid technology has focused on the treatment of these toxic chlorinated compounds. In this paper, recent developments of supercritical fluid technology for the decomposition of toxic materials are reviewed. A national project, starting in 2000, has developed two processes for the destruction of solid wastes containing dioxins or PCBs. One is a combined process of extraction/adsorption/SCWO (Ryotech Process) and the other is a hybrid SCWO process (Organo Process). In the former process, dioxins are extracted with supercritical carbon dioxide from a solid matrix and concentrated on an adsorbent. The dioxin-containing adsorbent is then destroyed by SCWO. In the latter process, solid materials containing PCBs are dechlorinated and neutralized in subcritical water. Then, the liquified materials are decomposed completely with SCWO. Mitsubishi Heavy Industries, Ltd. has also developed a SCWO process assisted by sodium carbonate. Solid organic materials containing PCBs are milled into a slurry and fed into a reactor with sodium hydroxide. These feed materials are completely destroyed by dechlorination and oxidation in the presence of sodium carbonate.

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The purpose of the study was to determine the amount of palm kernel oil extracted from a single palm kernel using a supercritical carbon dioxide (SC-CO₂) extraction technique. Further, the study sought to ascertain the values of the diffusion coefficient (D) of PKO in a single palm kernel by evaluation through a "Hot Ball Model", at constant temperature of 50°C and 60°C, and pressures ranges from 27.6 MPa, 34.5 MPa,41.4 MPa and 48.3 MPa respectively. Finally, the study also seeks to demonstrate the application of the diffusion coefficient values in relation to temperature and pressure. The diffusion coefficient for a single palm kernel was found to be in the range of 7.60 X 10^-7 cm²sec^-1 to 17.95 X 10^-7 cm²sec-1 for a constant temperature of 50°C and in the range of 6.09 X 10^-7 cm²sec^-1 to 15.07 X 10^-7 cm²sec^-1 for a constant temperature of 60°C with the pressure ranges from 27.6 MPa to 48.3 MPa. The diffusion coefficient was also observed to be dependent on pressure but weakly dependent on temperature.

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Morinda citrifolia (Noni), a plant that has been used in folk remedies for over 2000 years, has recently gained increased interest from the scientific professionals. The roots of Noni plants were used by Polynesians to produce yellow dye, but more importantly, they contain medicinally active components, namely anthraquinones. The compounds show several therapeutic effects, which include anti-bacterial, anti-viral, and anti-cancer activities as well as analgesic effects, which make them useful in several medical applications.
Conventionally, the compounds are extracted with ethanol, followed by evaporation to separate solvent from the product but this could leave residual solvents in the product.
In this study, subcritical water was used as a benign alternative solvent for extraction of the dried Noni roots. The effect of various operating conditions such as water temperatures (383 K, 443 K and 493 K), pressures (3MPa and 7MPa), and flow rates (2, 4, and 6 ml min^-1) on extraction yield and extraction rate were determined. At the operating temperature of 493 K, the extraction yield was the highest and was found to be about 80% of ethanol extracted. Pressure had no significant effect on the results for the range of temperatures studied. The flow rate of 6 ml min^-1 resulted in the highest extraction rate, but the extraction efficiency, as measured by the amount of anthraquinones extracted per unit volume of water was lower than that of 4 ml min^-1. The results of anthraquinones solubilities in subcritical water at various temperatures and the extraction mechanism will be discussed.

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Supercritical carbon dioxide extraction of the oil component of okara was investigated in the temperature range of 40 to 80 °C and pressure range of 12 to 30 MPa, with or without adding ethanol (EtOH) as entrainer. Results indicated that the oil component can be best obtained with a recovery of 63.5% at a relatively low temperature of 40 °C and a mild pressure of 20 MPa in the presence of sufficient amount of EtOH (in this case, 10 mol%) as entrainer. Based on gas chromatography-mass spectrometry (GC-MS) analysis, the extracts consisted mainly of fatty acids and phytosterols, and traces of decadienal, an aldehyde. Folin-Ciocalteau estimates of total phenols showed that addition of EtOH as entrainer increased the yield and the amount of phenolic compounds in the extracts. No significant effect of pressure on the amount of total phenols in the extracts could be established from the results. The amounts of two primary soy isoflavones, genistein and daidzein, in the extracts were determined using high-performance liquid chromatography (HPLC) methods. The yields of genistein and dadzein at the highest oil recovery were 12.1 and 9.4 %, respectively.

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Harmful heavy metal ions concentrations in scallop viscera wastes were found as: 26.58 ppm Cd (II), 23.27 ppm Cu (II), 371.55 ppm Zn (II) and 7.69 ppm Pb (II) (ppm=mg/kg dry wastes), respectively. The existence of these metals in such wastes have incurred big problem due to the large amount of wastes. Traditionally those wastes are burning in incinerator, but this treating retains harmful metal ions in out-streams residues, such as bottom and fly ashes. This study proposes a new method using sub-critical water treatment to produce useful material and simultaneous recovery of the metal ions. Reaction conditions involved temperature between 443-653 K, and reaction time 1-30 minutes. The results showed that metal ions are concentrated in solid-phase by increasing temperature to 653 K (6 times). The oil and fat extracted during this method, acted as a chelating agent to catch almost all metal ions from original wastes with order of recovery as Zn²⁺ > Cd²⁺ > Cu²⁺. The triglyceride and fatty compounds are responsible to make complex with metals in fat and oil phases. These two phases illustrated maximum concentration of metal ions in fat-phase at 513 K (max. 8000 ppm) and in oil-phase at 513-553 K (max. 340 ppm). Finally, aqueous phase illustrated lowest concentration of metal ions especially at temperature above 550 K. The distribution coefficient of metal ions defined as concentration in fat, solid and oil phases to concentration in aqueous phase were found highest in the fat (max. 44,000), following by solid (max. 27,000) and oil (max. 1,300).

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Kinetics of homogeneous hydrolysis and/or oxidation reactions in supercritical water is now considerably documented. However, understanding of the heterogeneous reactions on solid materials are still very much limited. In order to analyze the reaction progress around solid materials in sub and supercritical water, flow-type reaction cells were constructed where the reaction progress was directly observed by means of optical methods, mainly shadowgraph observation. In the case of activated carbon particles as one example, the rate of the supercritical water oxidation reaction was mainly determined by the oxygen transport. The reaction progress was also simulated successfully, using CFD calculation adopting an appropriate flow field and reaction mechanism. Similar investigation was carried out for the case of decomposition reactions of wood blocks in sub and supercritical water. In the subcritical region, the phenomenological first-order rate constant for the size decrease obeyed the Arrhenius law with an activation energy of ca. 80 kJ mol^-1. However, the rate constant decreased near the critical point and again increased at higher temperatures. This peculiar behavior may be understood considering that the principal reaction mechanism is hydrolysis in subcritical region and changes at higher temperatures to a mechanism of more radical-type. These results are valuable in designing an appropriate reaction process of supercritical water reactions.

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The applicability of supercritical water oxidation was investigated to the treatment of livestock excrement, which is a large quantity in Japan and almost 100 million tons in a year. In this method, the livestock excrement was incinerated completely and safely to carbon dioxide, water and nitrogen. The toxic and bad-smelling ammonia was decomposed rapidly and the toxic nitrogen oxide was not produced in supercritical water. As a result, the nitrogen atoms in the waste were converted to harmless nitrogen gas.
The effects of temperature, pressure, reaction time and oxygen supply ratio (ratio of supplied to stoichiometric amount of oxygen) on the combustion efficiency of carbon and product yields of ammonia, nitrous oxide were studied. As a result, the condition of 650°C, 15MPa, 15min and 1.2 of oxygen supply ratio was suitable for clean and complete burning of cow's excrement, where the combustion efficiency of carbon atom was almost 100% and the product yields of ammonia, nitrous oxide were almost zero. Furthermore the thermal energy recovered from the combustion process was estimated to be 2.87x10⁶ kJ per ton of raw excrement. It was equivalent to around 70 liter of C-heavy oil and corresponded to the reduction of about 56kg of carbon dioxide on carbon basis.

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The high activity of supercritical phase methanol synthesis was developed. Supercritical alcohol, a catalytic solvent, which conventionally promotes the heat and product removal, can also accelerate the new reaction route. It was shown that the activity of supercritical alcohol such as 2-propanol was higher than that of supercritical n-hexane, which only enhanced the activity by facilitating heat and product removal from the catalyst bed. The combination of supercritical fluid and catalytic solvent effects broke through the thermodynamic limitation of the reaction efficiency.

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On the technology utilizing supercritical water, it is a severe problem that the inorganic salts deposition caused by the decrease of the dielectric constant of supercritical water. Depending on the kind and concentration of salt, operation temperature and pressure, inorganic salts will cause the blockade in the process pipes during a short operation time. If the chlorinated organic compounds are decomposed by supercritical water oxidation (SCWO : 600°C, 25MPa), HCl is generated as the result of the decomposition reaction. This HCl is neutralized by an alkali solution and transformed to an inorganic salt. We have found the salt passage characteristics (the extent of salt entrained by the reactor effluent) varies with the kind of alkali under the supercritical water condition. If a NaOH solution is used as a neutral agent, HCl is transformed to NaCl. If a KOH is used, it is KCl is formed. The solubility of NaCl and KCl are almost same values (100mg/L) under the conditions of 500°C and 23MPa. When a NaCl solution having a concentration of 10,000mg/L was supplied to a straight pipe (4.5mmID×455mmL) at the flow velocities of 5.5∼176 cm/s in the supercritical water under these conditions, the NaCl solution caused blockade by salt deposition in a short operation time. On the other hand, when a KCl or a CaCl₂ solution (100,000mg/L) was supplied under condition of 600°C and 25MPa, these salts were completely recovered in the effluent without deposition for 4 hr operation time. These results indicate that solubility of a salt does not necessarily reflect its passage characteristic. In this paper we present some experimental results about the passage characteristics of inorganic salts.

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