| 摘要 |
PURPOSE:To obtain methacrolein in a 80% yield and in high yield per unit vol. of catalyst, by oxidizing isobutylene at a lower reaction temperature and in a shorter contact time, using a specific catalyst comprising Mo-Co-Fe-Bi-O added with V. Te or Nb. CONSTITUTION:Methacrolein is obtained by reacting isobutylene with molecular oxygen at 260-370 deg.C, most suitably 290-340 deg.C, in a contact time of 0.2-7 sec., most suitably 1-2.5 sec., preferably in the presence of steam in a reaction system, using a catalyst composition of formula (X is vanadium, niobium or tellurium; a, b, c, d, e and f are numbers of atoms: when a=10, b=3-10, c=1-7, d= 0.1-1.5, e=0.01-1 and f=34.6-54.1). In an example, the catalyst composition is obtained by mixing calculated amounts of ammonium molybdate, ammonium metavanadate, cobalt nitrate and bismuth nitrate in the presence of water to form a slurry, and calcining at 500-800 deg.C after drying. |
