| 摘要 |
A method for preparing an unsaturated aldehyde and an unsaturated carboxylic acid is provided to inhibit the excessive heat generation at hot spot, thereby reducing the temperature at hot spot effectively and increasing the yield of acrolein and acrylic acid from propylene or methacrolein and methacrylic acid from isobutylene or t-butanol. A method for preparing an unsaturated aldehyde and an unsaturated carboxylic acid comprises the steps of supplying a compound selected from propylene, isobutylene and t-butyl alcohol and an oxygen molecule to a reactor tube filled with a mixture oxide catalyst; and carrying out the catalytic oxidation of the compound and the oxygen molecule in gas phase, wherein the reactor tube is filled with a plurality of mixture oxide catalysts in such a pattern that the catalytic activity increases from the gas inlet to the outlet. The mixture oxide catalysts comprise molybdenum, bismuth and iron, show different catalytic activities, and are heated in the presence of a reducing compound. |
