抄録
In order to investigate the effect of catalyst on liquid phase air oxidation of petroleum hydrocarbons in the preparation of lower fatty acids, the authors studied the oxidation of petroleum naphtha at 160°C, 40atm, in the presence of Na, Mg, Al, Ca, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Zr, Cd, Sn, Ba, Ce, Pb, or Bi Catalyst (used as a salt of naphthenic acid or octylic acid), and observed the following results.
1. Compared with non-catalytic reaction, the induction periods were shortened by the salts of metals which belonged subgroup "a" in periodic table, and prolonged by the salts of metals which belonged subgroup "b".
2. Manganese salt was the only catalyst which increased the ratio of (secondary oxidation of intermediate products)/(primary oxidation of hydrocarbons). The addition of V or Cd salt was apt to suspend reaction.
3. The yield of formic acid was in the order of Mn>none>Co. The yield of acetic acid was in the order of Mn, Cu>none>Na, Co, Ni, Zn, Sn, Bi, Pb. The ratio of acetic acid to formic acid was in the order of Co>none>Mn.
These phenomena were observed regardless of the types of raw hydrocarbons-paraffinic or naphthenic-, and the types of anion component of catalyst-naphthenic acid or octylic acid-.
