| 摘要 |
The selective partial hydrogenation of a compound capable of being partially hydrogenated in admixture with a hydrogenatable compound incapable of being partially hydrogenated containing sulphur compounds of class B is effected in the presence of a supported elemental nickel catalyst and continuously or intermittently added sulphur compounds of class A; class A compounds are thiophenes, thiacycloalkanes having at least four carbon atoms in the ring and dialkyl monosulphides, class B compounds are sulphur and compounds with hydrogen and/or carbon not in class A. The nickel may be supported on alumina, kieselguhr, chalk, silica gel or sepiolite and may be sulphided at 0-200 DEG C. with a thiophene in the presence of hydrogen. Hydrogenation is effected at 50-250 DEG C., preferably in the liquid phase. The class A compound added is preferably separable by distillation and is separated from the product and recycled. The partial hydrogenation of isoprene in the presence of isohexenes is exemplied. |
