A study was made to investigate the hydrothermal synthesis and carbonation control of tobermorite from granulated blast furnace slag. The hydrothermal synthesis of tobermorite was performed under saturated steam pressure of 1.1 MPa at 183°C in suspensions (water/solid weight ratio 20) of different compounding ratios by adding silica stone and calcium hydroxide to slag. Characteristics of products were determined by means of X-ray diffraction, infrared spectrometry, scanning electron microscopic observation and chemical analysis.
Hydrogarnet was formed from hydrothermal reaction of the independent slag having Al/ (Si + Al) atomic ratio of 0.34 without additive. Consequently, the constituents in the slag were adjusted to Al/ (Si + Al) atomic ratio of 0.15 and Ca/ (Si + Al) atomic ratio of 0.80 by adding silica stone and calcium hydroxide to slag. The high crystalline tobermorite was formed alone by adjusting the constituents in slag.
The carbonation of tobermorite obtained by using the slag as main raw material was controlled considerably comparing with that of silica stone-Ca (OH) ₂ AlCl₃ system. Namely, it was a useful for the control of carbonation that a part of Ca²⁺ ion in tobermorite was substituted by Mg²⁺, Fe³⁺ and Mn²⁺ ions containing the slag.

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A hardened material with high strength can be obtained by the carbonation of calcium silicate compounds. In this study, the hardening properties of C₃S, β-C₂S and γ-C₂S were discussed. Powder of synthesized C₃S, β-C₂S and γ-C₂S were made as pellets and carbonated with 5% CO₂-bearing N₂ gas. The changes in the carbonation ratio, strength, porosity, etc. were measured. The carbonation products were calcium carbonates such as calcite, aragonite and vaterite, and amorphous calcium silicate carbonate hydrate. For β-C₂S, only aragonite was produced as calcium carbonate. As the results, a material with strength more than 100 MPa was obtained by carbonation of γ-C₂S pellet.

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Morphology-controlled hydroxyapatites (HAp) were prepared by phosphoration of various carcium carbonate used as seeds. Formation and coagulation processes of HAp were investigated by measuring the electrical conductivity and pH in the slurries and by means of X-ray diffraction, electron microscopic observation and measurements of IR spectra. When aqueous slurry of CaHPO₄ (DCPD) was titrated into aqueous slurry of aragonite, platy particles were deposited on the aragonite surface and then the rod-like crystal of aragonite were covered with precipitated particles. Platy particles were composed of low crystalline HAp. Aragonite in the center of aggregate was dissolved away in aqueous solution of CH₃000H- (CH₃000) ₂Ca. HAp aggregates with hollow were prepared. Ellipsoidal HAp aggregates with hollow were formed by phosphoration of vaterite used as seeds.
When phosphoric acid was titrated into aqueous slurry of calcite, on the other hand, spherical porous HAp aggregates were formed. Formation model of HAp aggregates with various morphology was proposed.

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本論文はクリーニング事業所での排水処理に関する研究報告である.
この事業所での排水は本洗い, すすぎ, のりずけの3種類に大別でき, これら排水を平均孔径8.5×10^-3μmの限外ろ過膜と2.0×10^-1μmの精密ろ過膜でそれぞれ処理した.その結果, 精密ろ過処理した排水と限外ろ過処理した排水とでは差異がみとめられず, 本洗い排水の有機成分 (TOC) は98%除去できた.しかし, のりずけ排水でのTOCは精密ろ過膜ではほとんど除去できなかった.
水質レベル向上として, TOC残存量の減少と洗濯用水としての水硬度成分Mg²⁺イオンとCa²⁺イオンとの除去に焦点をしぼり, 前者に対しては活性炭, 後者に対しては合成ゼオライトによる吸着除去をすすぎ排水に対して試みた.その結果, 吸着剤による高度処理水の水質は用水のそれらの値にきわめて近い値, すなわちTOCで24・3mg/l, Mg²⁺イオンで0.03mg/l, Ca²⁺イオンでは0.09mg/lを示した.

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本論文は大豆系食品 (豆腐) 製造所での排水処理に関する研究報告である.
この製造所での排水は浸せき排水, 寄せ込み排水, さらし排水の3種類に大別でき, これら排水を分画分子量が異なる3種類の限外ろ過膜, すなわち100,000, 10,000および3,000でそれぞれ処理した・その結果, 膜の分画分子量の相違による差異はみとめられず, 排水中の汚濁物質はほとんどが分子量3,000以下の有機化合物であった.また, ゲルクロマトグラフの分析結果より, これら排水中には分子量2・000前後と3,000前後のわずか2種類のタンパク質が含まれていることもわかった.
水質レベル向上として, 有機体炭素物質の減少とカチオン成分, すなわちMg²⁺イオン・C^a2+イオンおよびNH₄⁺イオンの除去に焦点をしぼり, 前者に対しては活性炭, 後者に対しては合成ゼオライトによる吸着除去をさらし排水に対して試みた.その結果, ゼオライトによるカチオン吸着は20分間で平衡に達し, その水質は用水のそれらの値を示した.しかし, 活性炭では有機体炭素物質を吸着減少させることができなかった.

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