In Japan, the amount of coal ash generated by power plants is increasing year by year, and its effective utilization is greatly requested. After a considerable three years effort of research and development of the technologies to manufacture the lightweight aggregates from coal fly ash, Kyushu Electric Power Co. Inc. and Kobe Steel, Ltd. constructed the commercial plant producing the lightweight aggregates utilizing coal fly ash, which operates efficiently and produces the high quality lightweight aggregates approved by the Japanese Ministry of Construction. The technology of manufacturing the lightweight aggregates from fly ash is based on the advanced pelletizing and sintering technology developed as a result of extensive experience in the iron-making industry.

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Wood powder suspended in an aqueous solution of alkali or alkaline earth salt was directly liquefied without a reducing agent such as 112 and/or CO. Heavy oils were obtained in 4550% yields under the following conditions: pressure, 110 atm; temperature, 300 °C;
holding time, 0-30 min; catalyst l oading, 5 wt%. The heating values were about 25 MJ/kg. Carbonate and hydrogencarbonate of sodium, potassium and calcium showed marked catalytic effects. Various kinds of wood and bark were used as a feedstock. In case of wood, heavy oil yields were 50%, irrespective of the indivisual species. In case of bark, however, heavy oil yields were as low as 20-27%. To improve the yields, steam explosion was applied to bark and as a result heavy oil yields increased to 33%.
Heavy oils obtained from wood in the above-mentioned manner were very viscous. Organic solvents such as propyl and butyl alcohols were added to the reaction system to reduce the viscosity of heavy oils. As a result, heavy oils with low viscosity were obtained in 50%yields. It was clarified that the additional alcohol functions not as a hydrogen donor but as a stabilizer of unstable breakdown products of wood. Because the additional alcohol was not consumed duririg the reactions, extended batch reactions in which water/2-propanol mixture was used repeatedly were examined. As a result, heavy oils were obtained in the yields of about 35% till the fourth run in five sequential runs.

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Rhodococcus erythropolis produces a kind of microbial flocculant. This bioflocculant was able to efficiently flocculate all the suspended solids tested in an aqueous solution. Among those tested were microorganisms such as E. coli. and baker's yeast, activated sludge, algae, kaolin clay, muddy water, river bottom sediment, ash and charcoal powder. The bioflocculant NOC-1 from Rhodococcus erythropolis has a wide flocculating activity against both organic and inorganic materials.
From an aqu eous solution of a water-soluble pigment, removal of the water-soluble pigment was attained by the bioflocculant NOC-1. The bioflocculant NOC-1 was able to efficiently flocculate and precipitate the soluble pigment in an aqueous solution tested. Among those efficiently tested were black ink, melanoidin pigment (blackish brown pigment) and black colored pigment of the black liquor of pulping industry.
Culture conditions for producing the bioflocculant w ere also tested. More than 90% of the flocculating activity was found in the culture broth and less than 10% in the cells.
This bioflocculant was purified, and was found to be composed mainly of p rotein. This bioflocculant is biodegradable flocculant which causes no problem of environmental pollution.
The microbial Alcaligenes latus produces a super bioabsorbent which can absorb u p to 1000times of water to its own weight about 5 times greater than currently available synthetic superabsorbents used in sanitary protection and baby diaper products.
Saline absorption rate is very high when compared with s ynthetic polymers and water retention in dry environments is also superior. This bioabsorbent may be environmentally safe for almost all applications, even those such as preventing drying out of desert soil and so on.

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A study was accomplished over recycling system of chromium(VI) in wastewater from the plants handling chromium(VI) by ion exchange resin.
An anion exchange resin selectively adsorbing chromium(VI) was adopted in the Cl-form to prevent from the hydroxide precipitation owing to the rise in pH during treatment.
Effects of pH and Cl-, SO₄^2-, Cr(III) contents in treated water on adsorption of chromium (VI), and differences between one bed method and two beds method were investi gated to develop a process, which can adsorb chromium(VI) to an ion exchange resin effectively and perfectly.
With a centralized regenerating process in industrial scale, the resins are perfectly regenerated and the chromium(VI) solution with high content and low impurity is recovered. This solution can be recycled as the raw material of chromium compounds.

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Experimental studies were carried out to obtain fundamental data on the effe ctive use of gypsum from flue gas desulfurization.
The properties studied were gypsum's chemical composition, particle size distribution, specific surface area, X-Ray diffraction, differential thermal analysis, flowability and floodability. Carr's flowability index of gypsum from flue gas desulfurization is 41-46 and floodability index is 53-57.5.
The gypsum f rom flue gas desulfurization consists of CaS0e 2 H 2O.
The whiteness of this gypsum is 49.3 and it's specific surface a rea is 868-1687 cm²/g. The first step dehydration reaction of
CaSO₄2H₂O_??_ CaSO₄.1/2 H ₂0 + 3/2 H ₂0
and the second step dehydration reaction of
CaSO₄ 1/2 H 2O _??_CaSO₄ + 1/2 H 20
is first order reaction. The activation energy for th e first step dehydration was found to be 14.2 '17.3 kcal mo1^-1, and the second step dehydration was found to be 34.3-35.0 kcal
The relation between the dry strength of gypsum from desulfurization and various water carrying capacities was measured and compared with literature values.
The strength of gypsum from desulfurization was 130-60
kg/cm². These values were stronger than literature values.
The dry strength of gy p sum- natural zeolite for molding materials was measured. Several properties of the gypsum-poly(vinyl chloride) were measured by JIS K 6723 method. Gypsum from flue gas desulfurization can be used as molding materials and as filler of poly(vinyl chloride) with the exception of insulated electric wires.

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The calcium lactate products, obtained by reaction of lactic acid with ground eggshell particles, contains finely divided protein films. The films obtained from 75, 225μm eggshell particles fitted well to the liquid phase, and were quite suitable as scrub (friction) particles.
On the other hand, the products with the particles less than 10 μm formed emulsions suitable for night cream marterials.
The lactate prod uct containing smaller protein films showed more effcient adsorption property. These results indicate that the eggshell is a good raw material for a cosmetic cream.

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Coal ash, which was formed as a by-product waste at coal-fired power station, was converted into zeolites by hydrothermal reaction in alkaline solution.
The reaction of coal ash with sodium hydroxide at 373 K under atmospheric pressure resulted in formation of Na-P 1, Na-A type zeolite, and hydroxysodalite. X-Ray microanalysis (EPMA) revealed that the zeolite zone was formed like egg white, covering the central core of fly ash particles (see Fig.2). Comparing SEM images at various times of hydrothermal treatment shown in Fig.5, formation of coal ash zeolites was suggested to proceed by the following sequence: (1) dissolution of zeolite components from the starting fly ash particles, (2) deposit and growth of amorphous microspheres on the surface of fly ash core, and (3)crystalization of the amorphous aggregates toward Na-P 1 or Na-A type zeolite. Na-A type zeolite, which was obtained through the above sequence, gradually changed with time to afford hydroxysodalite.
The zeolite was soluble in acid, and thus the weight percent of zeolite zone in fly ash zeolite could be evaluated quantitatively. The cation exchange capacity per unit weight of the acid soluble (zeolite) zone measured by NH4+ adsorption was quite close to that of synthetic zeolite (see Table 5).

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Calcium silicate-containing ion-exchangers have been prepared by h ydrothermal treatment of reutilizing burned waste paper sludges and cation-exchange characteristics of the prepared products have been investigated.
According to the amounts of added CaO, SiO2 and NaOH to the sludges, tobermorite and three types of zeolites (Analcime, Cancrinite and P-type Zeorite) were synthesized. Tobermorite was prepared at 0.7≤Ca/Si≤1.1, 0.15≤2 Na/Si≤0.5 and mixed products (tobermorite and three types of zeolites) were prepared at 0.25≤Ca/Si≤0.4, 0.15≤2 Na/Si≤1.0 at 150175 °C.
Ca tion-exchange characteristics of Ca²⁺ ions in the prepared products for Cs⁺, Co²⁺ and Zn²⁺ions in aqueous solution have been investigated at room temperature and atomospheric pressure, using a normal batch method. The prepared tobermorite product was found to easily ion-exchange the lattice Ca²⁺ ions in layer structure for Co²⁺ and Zn²⁺ ions in aqueous solution at room temperature and atomospheric pressure, ie, the product was found to be a “lattice ion ion-exchanger” introduced by one of the authors, Suzuki.

From the results, it can be concluded that the synt hetic compounds prepared from the burned waste paper sludges have been available for an ion-exchanger.

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Chemical precipitation with lime is an effective phosphate removal method when the concentration is relatively high such as industrial wastewater. However, lime treatment in its conventional form is not favored as a process for removing phosphate from wastewater for the following reasons. Since a high dosage of lime is required to raise the pH up to 10-42and large quantities of sludge are produced. The purpose of this study is to prepare a small volume of sludge and to precipitate calcium phosphate in the pH 8-9 region. Experimental results showed that the stepwise addition of lime was usefull to reduce sludge volume. A new process consists of two stage lime addition was proposed. For the first stage, the addition of slaked lime was done at a pH of below 6.5. The second stage was increased the pH to 8---9. The process reduced sludge volume to one-tenth compared with the one-time rapid addition of lime in the conventional process. A 10.6 mmol⋅dm^-3 Ca(OH)₂ dosage to 7 mmol⋅dm^-3 H₃PO₄ removed 98% of the phosphate at pH 8.7 and 99.5% of the phosphate in the presence of 1 mmoldm^-3 CaC1₂ at pH 8.5. The reduction in lime dose and sludge volume indicates a potentially improved conventional process.

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The starting material of various chromium compounds is sodium chromate that is avalilable from the chromium ore by firing with alkali under oxid izing atmosphere. At the same time, chromium slag containing Cr⁶⁺ is yielded as a by-product. The chromium slag was mixed with silicatematerial more than 30% of toal weight and they were pressed and fired at a temperature higher than 1200°C. Due to these treatments, we obtained the functional porcelain tile with high hardness, high intensity, high thermal coductivity and low specific electric resistivity.

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The accumulation of gallium from sea water containing 1 mg/^-1 of the element by Dunaliella sp. was strongly affected by the pH of sea water. The optimum pH for the accumulation was about 6.2. The accumulation of gallium proceeded rapidly, and reached a plateau within 1 h.79% of gallium accumulated in Dunaliella sp. was found in the cell wall.
The accumulation of gallium was increased by heat treatment of Dunaliella sp.. Iron and copper concentrations in Dunaliella sp. were largely affected by addition of gallium to sea water.

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We have developed a new process for recovery of Mo and Bi from used Sohio catalyst. Mo was preciptated as (NH₄)₃[PMo₁₂O₄] in the presence of PO₄^3- and NH ⁴⁺ on the HNO₃ decomposition of used catalyst and was recovered as (NH₄)₆[Mo₇O₂₄]4 H₂0. Bi was separated as BiC1O by neutralization from leaching solution containing Bi³⁺ and Fe₃₊. Then, metallic B i was obtained by reduction of BiCIO with carbon in molten alkali. Recoveries of Bi and Mo reached 85, -90%, and 85-88%, and their purities were 99.99% and 99%, respectively.

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The aquatic fern Azolla-Anabaena symbiosis whic h can grow without nitrogenous nutrient because of the N₂ fixing capability of Anabaena, was cultivated in a pond and its possible use as biomass was examined. The extent of growth in the pond (Komoike, Sakai) of 1200kg/100m² was less than that in a synthetic nutrient solution and in a diluted secondary efflue nt, The N₂ fixing activity of Azolla grown in the pond also decreased gradually when compared to that of the control which was grown in the synthetic nutrient solution.
A significantly higher content of dehydro-ascorbic acid (99.3 μ/gig) than that of L-ascorbic acid (O.5μ/gig) in fresh Azolla grown for 3 d, which is charac cteristic in view of possible use of Azolla as animal feed.
In the methane gas ferm entation experiment, the extent of conversion to gas increased by about 40% by the preheating Azolla-plants at 100 °C.

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The aim of this work was to develop the pretreatment and fermentation processes to convert lignocellulosic wastes into ethanol. The proposed process consists of steam explosion pretreatment followed by direct fermentation using thermophilic anaerobes. Ethanol production from lignocellulosic materials was demonstrated in a scaled-up test plant containing a pretreatment section with a capacity of 1 ton of wood per day and a fermentation section having a 5 m³ fermentor.
Wood chips o f cedar (softwood) and white birch (hardwood) were treated with saturated steam. Steam explosion of cedar chips for 10 min at 40 kg/cm²G (250 °C) gave the maximum yield of digestible cellulose. Holocellulose yield was 43% and enzymatic digestibility was improved to 90% under these conditions. Steam explosion of white birch chips for 10 min at 22 kg/cm²G (220 °C) gave 51% of holocellulose yield and 94% enzymatic digestibility.
Steam exploded cedar, steam exploded white birch and pure cellulose w ere fermented at 60°C by Clostridium thermocellum HS-1 which was newly isolated from a hot spring soil sample. The fermentation of steam exploded cedar was started when the initial holocellulose concentration in the medium was 20 gll. The final ethanol concentration in fermented broth reached 0.64 vol% which represents a yield of 45%. The steam exploded white birch was fermented to a final ethanol concentration of 0.74 vol% which represents a yield of 52% under the same conditions. The fermentation of pure cellulose gave a final ethanol concentration of 2.71 vol% and a yield of 48% from initial cellulose concentration of 80 g/1.
These technologies can be applied to fuel ethanol production from not o nly lignocellulosic wastes such as forestry and agricultural residues but also municipal cellulosic wastes.

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Enzymatic degradation of eleven types of microbial and synthetic polyesters; poly[(R)-3hydroxybutyrate] (1), poly[ (S)-3-hydroxybutyrate] ( 2 ), atactic poly[ (R, S)-3-hydroxybutyrate]( 3 ), poly[ (R)-3-hydroxyvalerate] ( 4 ), poly (3-hydroxypropionate) ( 5 ), poly[ (R)2-hydroxypropionate] ( 6 ), poly(4-hydroxybutyrate) ( 7 ), poly(5-hydroxyvalerate) (8 ), poly (6-hydroxyhexanoate) ( 9 ), poly(ethylene adipate) (10) and poly(1, 4-butylene adipate) (11)was investigated at 37 °Cand pH 7.4 in the aqueous solution of extracellular P(3 HB) depolymerase from Alcaligenes faecalis. The rate of enzymatic degradation decreased in the following order; (1)=(5)>(10)>(3)>(4)=(7)>(2)=(6)=(8)=(9)=(11)=0.
The relatio n between the molecular structure and the rate of enzymatic degradation of polyesters has been discussed.

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Oxidation of poly(vinyl chloride) (PVC) with oxygen was carried out in NaOH solutions in the range of NaOH concentration (1-25 molikg-H₂0), temperature (423-533 K) and the partial pressure of oxygen (1-10 MPa). The oxidation of PVC proceeded noticeably above 423 K. The major products of the oxidation were oxalic acid and CO_2-, . A small amount of malonic acid was also found as a minor product. The rate of formation of both oxalic acid and CO₂, increased with raising temperature and increasing the partial pressure of oxygen, but decreased with increasing NaOH concentration. However, the yield of oxalic acid increased with increasing NaOH concentration until 15 mol Na0H/kg-H₂O. The yield of CO₂ attained 50 C% in the initial stage of the oxidation, thereafter it remained almost constant. The maximum yield of oxalic acid and the yield ratio of oxalic acid/CO2 attained 38.5 C% and O.76, respectively, without any pretreatment prior to the oxidation. The yield of oxalic a cid and CO₂ were 10.6 and 9.8 C% respectively, when 2.0 wt% CuO was added to PVC as a catalyst. The yields of oxalic acid and CO₂ were improved to 45.1 and 5.1 C%, respectively, by pretreatment of sample in air at 473 K for 1 h, prior to oxidation in NaOH solution. Under the present pretreatment conditions, 42.2% of chlorine in the original sample were eliminated as HCl. These results indicated that oxalic acid was preferentially produced to CO₂ adding the catalyst or by the pretreatment.

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[in Japanese]

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Titanium-containing organic thin films were prepared from titanium tetraisopropoxied(TIPP)by plasma-polymerization and changes of electrical conductivity in the presence and absence of organic fuel gases were investigated. It was found that titanium containing organic thin films increased its conductivity rapidly in the presence of organic fuel gases such as methanol, ethanol, 1-butanol, t-butyl alcohol, and acetone. Conductivity change is presumably based on the absorption-desorption equilibrium of oxygen gas which react with organic gases at the surface of the film. The mechanism was briefly discussed.

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Solubility of MX₂ type metal salts in polyethylene oxide (PEO) with different molecular weight (200-600) was determined and summarized. The terminal hydroxyl groups of PEO were found to be effective in increasing the salt solubility. There was however no clear relationship between the solubility in PEO and that in water. The effect of salt concentration on the ionic conductivity showed a maximum because of the compensation of the increase of carrier ion concentration and decrease of their mobility. The PEOs containing MX₂ type salts show similar characteristics to those of PEOs containing MX type salts. The ionic conductivity of PEOs containing these salts shows a positive relation with the lattice energy of the salts contained. PEOs with lower molecular weight and containing salts with lower lattice energy provided higher ionic conductivity.

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Processes of preparation of vanadium oxides supported on alumina by chemical vapor deposition (CVD) usingV0(0C₂H₅)₃ were investigated by means of infrared spectroscopy (IR), thermogravimetry (TG), and temperature programmed decomposition (TPD). It is concluded that both OH groups and Lewis acid sites are active sites for the adsorption-decomposition. of VO(0C₂H₅)₃ to form V₂0₅ overlayers. X-Ray diffraction (XRD) and extended X-ray absorption fine structure (EXAFS) revealed that V₂0₅ was present as thin layers on Al₂0₃. In 2propano1+02 4-eaction, V₂0₅/Al₂0₃ produced acetone with high selectivities as compared to bulk V₂₀₅.

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Pure zinc silicate was synthesized by the reaction of sodium metasi licate with zinc chloride in a aqueous solution. The reaction product was analyzed by X-ray diffraction, atomic absorption and thermal analysis, and it was confirmed to be zinc silicate, Zn₂SiO₄. The reactions can be assumed to be proceeded by the following steps.
_??_

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Suspensions of thallium tris- and tetrakis(1-pyrazolyl)borates T1(BRPz₃) (Pz=1-pyrazolyl R=Pz, H) and cis-[RuC1₂(dmso)₄](dmso=dimethyl sulfoxide ligand) in CH2C12 were refluxed for 6 h, and afforded a boron-free pyrazole complex, [RuC1₂(PzH)(dmso)3] [1] as a pale yellow powder. Isolated yields were 13 and 17% from BPz₄ and BHP_z3 salts, respectively. Bond cleavage between boron and 1-nitrogen atoms occurred for the BRPz₃ ligands in the course of the reactions. All of the three dmso ligands in 1 were associated with their S-bonded coordination mode on the basis of 'H-NMR and IR spectroscopy. The singlet 'H-resonance (CDCl₃) at δ 3.53 was attributed to two spectroscopically equivalent m ethyl groups of one dmso ligand. On the other hand, the remaining two dmso ligands showed methyl-proton signals at δ 3.17 and 3.46, of which the mutual long-range coupling (⁴JHH)was observed in the H-1-H COSY, indicating spectroscopic nonequivalence of the two geminal methyl groups in the respective ligands. As a whole, the complex 1 was concluded to have the facial configuration of three S-bonded dmso ligands around ruthenium. In addition to 1, [RuCl₂(PzH)₂(dmso)₂] was formed as a minor product, by use of a large excess of PzH in the reaction with [RuCl₂(dmso)₄].

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The effect of carbon black on direct atomization of various molybdenum salts dispersing in water and the differential determination of salt mixture using flameless AAS by aid with the effect were investigated.
The mixtur e of two salts of molybdenum disulfide, molybdenum trioxide and molybdenum monocarbide were determined without chemical pretreatment. The mixture which was dispersed in water with carbon black by ultrasonic agitator was directly atomized. The constituent ratio of MoS₂ and Mo0₃, etc. in the mixture was determined using the calibration curve plotted with the difference of enhancing atomization effect with carbon black. We have applied the method to practical analysis of molybdenite and obtained satisfactory results, (MoS₂; 96.0%, MoO₃; 4.0%).

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The behavior of hydrogen ions and potassium ions in a culture solution was examined during germination and growing period of radish (Kaiware daikon). The radish was grown in the culture solution made up of pure water or in the solution containing potassium chloride. The germination rate was ca.80-90%. During the germination period (ca.20 h) from the seed snow in the culture solution of pH 6, 5 and 4, the concentration of hydrogen ion shifted to ca. pH 7 with the passage of time, and the concentration of pottassium ion increased from zero up to 10^-4 mol/dm³. On the other hand, in the growing period (ca.1 week), radish absorbed almost all potassium ion liberated in the germination period and liberated hydrogen ion.
Next, in order to examine' the influence of concentration of potassium ion in the culture solution, the radish was grown at pH 5 in solutions containing potassium ion of concentration ranging from 10^-5 to 1 mol/dm³. The results showed that the incorporation of hydrogen ion was suppressed with the increase of the potassium ion concentration. However, when potassium ion becomes more than O.1 mol/dm³, the radish was poorly germinant and not entirely grown.
The correlation coefficient of correlation between hydrogen and potassium ion concentrations in the culture solution was between 0.84--- O.96, and a good negative correlation was observed between them.

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Bromination of 2-acetamidopyridines [1], such as 2-acetamidopyridine [1 a], 2-acetamido3-methylpyridine [1 b], 2-acetamido-4-methylpyridine [1 c], 2-acetamido-5-methylpyridine [l d ], 2-acetamido-6-methylpyridine [1 e] and 2-acetamido-4, 6 -dimethylpyridine [1 f] was investigated.2-Acetamidopyridines HBr₃ [ 2 ] were prepared from the reaction of [1] with 48% HBr and Br₂. Compounds [ 2 ] were treated in water at 40 °Cto give 2-acetamido-5bromopyridines [ 3 ] in good yield via generation of Br₊OH_-. For example, 2-acetamido-5bromo-4-methylpyridine [3 c] was obtained from 2-acetamido-4-methylpyridine HBr3 [2 c]. Compounds [ 1 ] were reacted with Br₂ in basic buffer solutions such as Na₂HPO₄ or CH₃CO₂Na to give 2-acetamido-5-bromopyridines [ 3 ] in good yield. It is estimated that Br+NaHPO₄or Br+CH₃CO₂- is active species in these systems.

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