摘要 |
1,255,578. Isoprene. TAKEDA YAKUHIN KOGYO K.K. 31 July, 1970 [2 Aug., 1969], No. 37116/70. Heading C5E. Isoprene is produced by reacting isobutylene and formaldehyde in the vapour phase in the presence of a solid acid catalyst comprising silica and antimony oxide. The catalyst may also contain one or more of Ti, Zr, V, Cr, Mo, W, Mn, Fe, Co, Ni, Cu, Zn, Ag, Cd, Mg, Ca, B, Al, Tl, Sn, Pb, P and Bi. The molar ratio of isobutylene : formaldehyde is preferably greater than 3 : 1 and the reaction temperature higher than 180‹ C. |