From the result of reduction of nitro compound by use of N-3 catalyst in the preceeding report it can be explained that the rate equation is first order for nitro compound and zero order for hydrogen. In the case of using N-103 catalyst, with difference from N-3 catalyst, the reduction of nitrobenzene to aniline was disturbed by the intermediates and the rate equation derived from the consideration that the intermediate was removed by aniline was able to explainthe expermental results. The reductions of various compouds which are consideredas the intermedi ate compounds, have been carried out, and from there it can beassumed that the intermediate to disturb these reduction is nitrosobenzene .
In order to prove the mechanism of reduction of nitrobenzene in the second report, addition of aniline to nitrobenzene was tried and found to increase the rate of reduction. This fact was applied on the other nitro compounds and theaddition of amine was found effective. These experimental results good agreement with the rate equation given in the second report. Also, by adding ani line tothe substance considered as intermediate compounds of nitrobenzene to aniline its effect for reduction has been investigated.
As in the third report, phenylhydroxylamine showed the greatest reduction velocity among intermediates of reduction of nitrobenzene and itself was found to have reducing power. Then, as it was assumed that phenylhydroxylamine had a ability to increase the reduction velocity and remove nitrosobenzene which disturbs its reduction in the reduction course of nitrobenzene by use of N-103 catalyst by additon of phenylhydroxylamine to nitrobenzene containing 1 % of nitrosobenzene, it was ascertaind to be effective for reduction to aniline. Also, its addition to a difficultly reducible dinitro compound gave diamino compound easily. Under the same condition the integral equation of reduction velocity formulated from the above reaction mechanism showed the same type with the equation (6) in the second report and the experimental result could be explained well from this consideration. In addition the reductions of several other nitro compounds were carried out by use of N-103 catalyst.
Synthesis of acetaldehyde by the oxidation of ethylene with PdCl2 catalyst has been invtseigated by separating it into a carbonylation reaction and a metal oxidation reaction, respectively, in vapor-liquid catalytic reaction. It was concerned that the velocity of absorption of ethylene in the carbonylation reaction depends on a diffusion velocity or a reaction velocity according to the condition and the following equation was found to be applicable in the latter case:-dC2H4/dt=1.8×106exp(-7.4×103/RT)[Pd++]1.0[Cl-]-2.0P1.0C2H4 In the metal oxidation reaction the velocity was usually decided by the oxidation step of CuCl. It was confirmed that the velocity of absorption of oxygen were controlled by diffusion step or reaction step and the following equations were found to be applicable in each case: Reaction-controlled. -do2/dt=2.3×102exp(-3.4×103/RT)Po21.0 Diffusion-controlled. -do2/dt=3.4×10-2Po21.0G1.1 Then it was clarified that above results are applicable for a continuous reaction by combination of these two reactions.