| 摘要 |
Oligomers of butene are cracked or depolymerized by contact at elevated temperature with a phosphate of aluminium and/or boron. The feed is preferably di-isobutene and/or tri-isobutene or a n-butene-isobutene copolymer. The catalyst may be supported, e.g. on silica gel or activated alumina and may also contain 0,03-1% of nickel as a salt thereof. Cracking is effected at 220 DEG -320 DEG C. and at or near atmospheric pressure, e.g. 4-8 atmospheres with a throughput of 0,5-3 kg./litre of catalyst/hour. The product from di-isobutene is isobutene, tri-isobutene also yields the dimer which may be separately cracked or recycled. Iso-butene-n-butene copolymers yield higher than theoretical amounts of isobutene. |
