酒造用活性炭を特集するにあたり, 活性炭メーカーの立場からユーサーにとって必要な商品知識として活性炭の歴史, 製造法, 特性, 吸着理論および基礎的な概念について平易に解説していただいた。

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Carbonized plam kernel shell (a) was steam-treated to prepare activated carbon and activation characteristics in preparation as well as adsorption charateristics of the resulting activated carbon were compared with those of a commercial coconut shell carbon (b).
Reaction rate of (a) with steam is smaller than that observed with (b).
The adsorption behavior and pore size distribution suggest that activated carbon from (a) is suitable for smaller molecular absorbates.
On the adsorption of styrene monomer in the fixed beds, activated carbon from (a) was superior to a commercial activated carbon from (b) with regard to break-through time and retentiveness of adsorption.
The experimental results indicate that activated carbon from (a) has ability of deodorization as Well as decolorization.

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パラジウム塩と活性炭よりなるオレフィン酸化の触媒系についてその活性点に関して検討した。触媒は水素で還元することにより失活したが,反応条件下で塩化水素を添加することにより容易に活性を回復した。酸素を供給しないにもかかわらず担持した塩化パラジウムに対して4倍モル以上のアセトアルデヒドが生成したが,陰イオン(塩素イオン)も多量に流出した。周期的酸化還元反応により次の結果を得た。
1)酸素を反応系に供給すると触媒活性は急激に増大し,無酸素反応(還元反応)前の活性の70～80%に回復した。2)無酸素反応を行なった場合,低温で行なうと陰イオンの流出はきわめて少量であったが,活性の低下は高温の場合より著しかった。
これらの実験事実に基づいて陰イオン,パラジウム,活性炭等の作用について考察した。
活性炭上の表面酸化物はパラジウムの再酸化反応に対して積極的な役割を演じなかった。

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Four methods were examined to prepare porous carbons with controlled micropores from phenolic resins. Firstmethod carbonizes phenolic resins synthesized from formaldehyde and various phenols. At the carbonization temperatureof 600°C, phenol-resin or 1, 2, 3-trihydroxybenzene-resin had uniform micropores of 0.4 to 0.45nm in diameter, whereas 1, 5-dihydroxynaphthalene-resin had larger micropores of 0.4 to 0.5nm in diameter. The larger pores werefound to be formed through the devolatilization of 1, 5-dihydroxynaphthalene remaining in the resin. This presenteda possibility to control micropores by devolatilizing the substance incorporated in the resin during carbonization.
Second method carbonizes resins prepared from the mixture of two different phenols. The mixed resin synthesizedfrom 1, 2, 3-trihydroxybenzene and 1, 5-dihydroxynaphthalene had large micropores of 0.9 to 1.1nm which did notexist in either 1, 2, 3-trihydroxybenzene or 1, 5-dihydroxynaphthalene-resin. This presented a possibility to controlmicropores by carbonizing mixed resins.
Third method uses resin of different cross-link densities as starting materials. However, the cross-link densitydid not affect significantly the size of micropores of carbonized resins.
Fourth method is to control the carbonization by loading mechanical pressure, and consequently to controlmicropores of carbonized resins. This method was found to be effective to decrease the size of micropores.

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サラン廃棄物を原料とする分子ふるい炭素の製造について検討した。サラン廃棄物を温度800℃で脱塩酸炭化したのち,これにコールタールレピッチを4.4～26.1wt%,亜硫酸パルプ廃液を13.0wt%加えて,ディスク型のペレタイザーを用いて平均径0.7mmの球形ペレットを製造した。得られた球形ペレットを窒素雰囲気中で温度800℃に1.5時間熱処理した。熱処理炭について,二酸化炭素,ブタン,イソブタン,ネオペンタシの25℃における吸着等温線を測定した。そめ結果,サラン廃棄物の炭化物にコールタールピッチを加えて熱処理することによって分子ふるい炭素を製造できることがわかった。サラン廃棄物からの分子ふるい炭素は分子径6.2Aのネオペンタンを吸着しなかった。コールタールピッチの添加量が12.6.14.4,17.0wt%の分子ふるい炭素はゼオライト5Aに類似した細孔径を有し,分子径4.3Åのブタンと分子律5.0Åのイソブタンに対してすぐれた分子ふるい作用を示すことがわかった。

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麹菌 (Aspergillus oryzae) の分生胞子を包括法によリアルギン酸ナトリウムのゲル中に固定化後, 麹汁培地で静置あるいは振とう培養することにより固定化麹菌を調製することができた。この固定化麹菌を用いて清酒中の異臭の除去を試みたところ, 老香, アセトアルデヒド臭及び木香に対して特に高い効果が認められた。また, ゲル中での過度の菌体増殖を抑えることにより, 麹臭の発生を低くすることができ, 麹菌体を直接添加した際に生ずる麹臭の付着という弊害を除くことができた。
このほかに, アセトアルデヒド臭の除去効果は, 固定化麹菌の還元作用によることを示唆する結果も得られた。

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The Cr(VI) in an acidic solution was reduced to Cr(III) and was most efficiently adsorbed at pH about 5 by the retorted shale from Thailand oil shale (spent shale). It is considered that these behaviors of Cr(VI) in an aqueous solution is due to the action of the deposited carbon in the spent shale, which was activated with various salts of Ca, Mg, Na, K and the like during the retorting of the oil shale.

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The microscopic surface structure of carbons, prepared from cyclodextrin (CD) and amylose (AM), was determined by a physical adsorption-desorption measurement of carbon dioxide at 195K and by a temperature programmed desorption (TPD) method. The topography of the samples was also observed by Scanning electron microscopy.
These carbons were obtained by a heat-treatment of the raw materials or those preoxidized. By means of the preoxidation of CD, the yield of the carbon was increased from 31.1% to 75% at a heat-treatment temperature (HTT) of 973K. By the same treatment, the surface area of the carbon increased from 385 to 491m²/g for the CD-carbon-HTT-1273K. The surface area of the AM-carbon-HTT-1273K non-oxidized was 301m²/g.
The pore distribution calculated from the adsorption-desorption measurement agreed well with the results of TPD spectra. The carbon obtained from CD (preoxidized) had large surface area and narrow distribution in micro pore.
There was no significant difference in pore distributions between two kinds of carbons (from CD and AM). Both of these carbons would have homogeneous pores.

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Adsorption behavior of some metal ions by an activated carbon treated with 8-hydroxyquinoline (HOx-AC) was studied for the preconcentration of trace metals. The HOx-AC was prepared as follows : 20 g of pre-dried activated carbon was added into a conical flask containing 500 ml of 8-hydroxyquinoline solution (20 g/l ethanol solution) and the mixture was stirred for 24 h at 20°C. The activated carbon was separated by suction filtration and air-dried. It was washed two times with 500 ml portions of 0.2 M acetate buffer solution (pH : 4), and then washed four times with 500 ml portions of distilled water and air-dried again. Finally it was dried at 40°C for 60 min. The adsorbed amount of 8-hydroxyquinoline was 154 mg on 1 g of activated carbon. The HOx-AC can be used in the pH range from 5 to 10 for the adsorber. The adsorption capacity of Cu (II), Zn(II), Cd(II), Ni(II), Mn(II), Ca(II) and Mg(II) was determined. Effect of pH on the recovery of metal ions was also studied. The recovery of 25μg each of Cu(II), Zn(II), Cd(II) and Mn(II) in 500 ml of 0.5 M sodium chloride solution was more than 95%. The adsorption rate was rapid. The HOx-AC proved to be useful for the enrichment of trace metals.

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毛管構造のわかつている多孔性バイコールガラスに沈積した酸化鉄について,分散状態と触媒活性との関係を検討した。酸化鉄沈積量f-0.064～0.206(g/g-carr)の試料について,0℃におけるn-キサンの執着.脱着等温線を測定した.酸化鉄が担体を構成している単位粒子の表面に均一に分散しているとすると, fの増加こともなう等温線の変化がよく説明できる.一方パルス法により,f-0～0.206の触媒についてシクロヘキサンのベンゼンへの脱水素反応活性を測定した。触媒活性は最初はfに比例して増加するが,fがさらに大きくなると一定値に収敏する。活性が一定になるところでの沈酸化鉄層の厚さはα型酸化鉄の格子定数,5.4Åに近い。沈積酸化鉄量がきわめて少なければ完全な活性を示さないであろうが,少なくとも格子定数以上の厚さになれば十分な活性を示すと考えると,f の増加にともなう活性の変化を, 収着法の場合と同一の分散モデルで無理なく説明できることを述べた。

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