| 摘要 |
<p>A catalyst for use in the production of acrylic acid by catalytic gas phase oxidation of acrolein, comprising active substances represented by general formula Mo(a)V(b)A(c)B(d)C(e)D(f)O(x) wherein Mo represents molybdenum, V represents vanadium, A represents at least one element selected from the group consisting of tungsten and niobium, B represents at least one element selected from the group consisting of iron, copper, bismuth, chromium, antimony and thallium, C represents at least one element selected from the group consisting of alkali metals and alkali earth metals, D represents at least one element selected from the group consisting of silicon, aluminum and tinanium, and O represents oxygen; and further, a, b, c, d, e, f and x represent atomic ratios of Mo, V, A, B, C, D, and O respectively, and when a=12, then b=2 to 14, c=0 to 12, d=0 to 6, e=0 to 6 and f=0 to 30 and x is a numerical value determined depending upon the oxidation states of the other elements, and characterized by having a specific surface area of 0.50 to 15.0 m<2>/g, a pore volume of 0.10 to 0.90 cc/g and a pore diameter distribution in which the pore diameters are distributed concentratedly in the ranges of from 0.1 to less than 1.0 mu m, from 1.0 to less than 10.0 mu m and from 10.0 to 100 mu m. The catalyst can be prepared, with good reproducibility, by charging an unfired catalyst material powder composition into a centrifugal flow coating apparatus to form particles having an average diameter of 2 to 10 mm, and then firing the particles.</p> |
