| 摘要 |
PURPOSE:To obtain high-purity isobutylene, by bringing an isobutylene feed containing butene-1 into contact with a group VIII metallic catalyst, such as Pd, in the liquid phase in the presence of a small quantity of hydrogen under specific temperature condition, isomerizing the butene-1 to butene-2 and removing the butene-2 by distillation. CONSTITUTION:An isobutylene feed containing 0.2-2.0wt.% butene-1 is brought into contact with a group VIII metal-containing catalyst in the liquid phase in the presence of hydrogen in a quantity of 0.002-0.008mol. (preferably 0.003-0.007mol.) based on 1mol. feed at 10-100 deg.C (preferably 30-70 deg.C) to isomerize the butene-1 to butene-2, which is then removed by distillation to afford the aimed high-purity isobutylene with hardly any content of the butene-1 for producing butyl rubber. Pd is preferred as the group VIII metal and 0.01-1.0wt.% Pd is supported on a carrier (preferably alumina). Loss of the isobutylene by conversion thereof into isobutane can be suppressed within 0.3% by the above-mentioned method. |
