Patent ID: 7429678
Filing Date: 2008-09-30
Classification: B01J,C07C

Abstract:
1. A process for production of acrylic acid, which is a process comprising the step of carrying out a catalytic gas phase oxidation reaction of acrolein with molecular oxygen or a molecular-oxygen-containing gas, thereby producing the acrylic acid; wherein the reaction is carried out in the presence of a composite-oxide catalyst shown by the following general formula (1): (wherein: Mo is molybdenum; V is vanadium; W is tungsten; Cu is copper; A is at least one element selected from among cobalt, nickel, iron, lead, and bismuth; B is at least one element selected from among antimony, niobium, and tin; C is at least one element selected from among silicon, aluminum, titanium, and zirconium; and O is oxygen; and further, a, b, c, d, e, f, g, and x denote atomic ratios of Mo, V, W, Cu, A, B, C, and O respectively; and, in the case of a =12, the following inequalities are satisfied: 2≦b≦15; 0<c≦10; 0<d≦6; 0<e≦30; 0≦f≦6; and 0≦g≦60; and x is a numerical value as determined by the oxidation state of each element); wherein said composite-oxide catalyst is prepared by the steps of: a) uniting a starting material for element A with a starting material selected from among molybdenum, vanadium, and copper to form a united material, then optionally drying said united material and optionally heating said dried material, such that a composite A is obtained; b) mixing said composite A and starting materials for other elements to obtain a starting material mixture containing said composite A; c) drying said starting material mixture containing said composite A to obtain a dried material containing said composite A; and d) calcining said dried material containing said composite A to obtain said composite-oxide catalyst.