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Methane selective oxidation to methanol using a nonthermal pulsed plasma was investigated at room temperature and atmospheric pressure. The maximum selectivity of methanol was 47% at the methane conversion of 1.9%. It was found that the methanol selectivity is more sensitive to the input power for discharge than to oxygen concentration and discharge length. Effects of input power for discharge, oxygen concentration, and discharge length on methane conversion and selectivity of each product were investigated.

The optimization of C 1 -oxygenates for the selective oxidation of CH 4 in the gas-phase reaction of CH 4 -O 2 -NO has been examined with kinetic models utilizing the software packages of CHEMKIN III. The variations of simulated selectivities of the products in the reactions reproduced well the experimentally obtained values except for those of CH 3 OH in a region of less than 10% CH 4 conversion. The effects of several experimental conditions, i.e., SV, CH 4 /O 2 , NO concentration, NO/NO x (x ) 1,2) on the selectivities of C 1 -oxygenates were examined. The ratio of CH 4 /O 2 ) 2 and 0.5% NO concentration for the feed gas were the best reaction conditions for getting the highest yield of C 1 -oxygenates through experimental conditions, and its yield was 57% at 10% CH 4 conversion. All of the simulated values of the selectivities of C 1 -oxygenates could not exceed this value in the examined reaction conditions. If the decomposition reactions of CH 2 O and CH 3 -OH with OH radicals in the course of the reactions were omitted, the predicted value of C 1oxygenates would be 77% at 10% CH 4 conversion.

The adsorption of α-chymotrypsin onto plant biomass charcoal (PBC), which was prepared from plant biomass wastes such as bagasse and dumped adzuki beans by pyrolysis, has been examined. The PBC was characterized by SEM, specific surface area, and pore size distribution. The adsorption isotherms were successfully correlated by the Freundlich equation. The amount of α-chymotrypsin adsorbed on PBC was dramatically dependent upon the solution pH and temperature. Maximum adsorptions of α-chymotrypsin on adzuki bean charcoal and bagasse charcoal were observed at weak acidic and near neutral pH, respectively. The amount of α-chymotrypsin adsorbed on PBC decreased with an increase in the concentration of salts. Plots of the amount of α-chymotrypsin adsorbed on PBC versus temperature exhibited an optimum temperature.

Catalytic deoxygenation of various N–O bonds using rhodium carbonyl compounds under a water gas shift reaction was studied. A catalyst system of Rh6(CO)16 and N,N,N′,N′-tetramethyl-1,3-propanediamine was found to have high activities for the following deoxygenations: 1) conversion of nitrobenzenes to anilines, 2) aliphatic nitro compounds to nitriles, 3) oximes to nitriles, 4) hydroxylamines to amines, and 5) amine oxides to amines. The above-mentioned rhodium catalyst system was heterogenized by using amino-substituted polystyrenes. Rh6 and Rh14 carbonyl clusters of [Rh6(CO)15H]−, [Rh6(CO)15]2−, and [Rh14(CO)25]4−, were formed on the polymer surface. The characteristic features of the catalysis of the polymer-bound rhodium cluster complexes are described in relation to the corresponding homogeneous ones.

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