| 摘要 |
<p>A process comprising producing acrolein and acrylic acid by vapor phase catalytic oxidation of propylene with molecular oxygen or molecular oxygen-containing gas using a catalyst filled fixed bed shell-and-tube reactor, which process is characterised in that: (1) the catalyst layer in each of the reaction tubes in the fixed bed shell-and-tube reactor is divided into two or more layers in the axial direction of the tube; and (2) each reaction zone is filled with more than one catalyst such that the catalytic activity increases from a starting gas inlet side of each reaction tube toward an outlet side thereof; wherein the catalysts are complex oxides of formula (1): MoaWbBicFedAeBfCgDhEiOx wherein Mo is molybdendum; W is tungsten; Bi is bismuth; Fe is iron; A is one or more element selected from cobalt and nickel; B is one or more element selected from phosphorus, tellurium, arsenic, boron, antimony, tin, cerium, niobium, lead, chromium, manganese and zinc; C is one or more element selected from alkali metal elements; D is one or more element selected from alkaline earth metal elements; E is one or more element selected from silicon, aluminum, titanium and zirconium; and O is oxygen; a, b, c, d, e, f, g, h, i and x denote the atomic ratios of Mo, W, Bi, Fe, A, B, C, D, E and O, respectively, such that when a is 12, b is from 0 to 5, c is from 0.1 to 10, d is from 0.1 to 10, e is from 1 to 20, fis from 0 to 5, g is from 0.001 to 3, h is from 0 to 3, it is from 0 to 30, and x is a numerical value determined by the extent of oxidation of each of the elements. and are different from each other in ( alpha ) occupying volume, ( beta ) calcining temperature and/or ( gamma ) kind and/or amount of alkali metal element.</p> |
