申请人:BASF Aktiengesellschaft
公开号:US04538009A1
公开(公告)日:1985-08-27
Substituted phenols of the general formula I ##STR1## where R.sup.1, R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are each hydrogen or an aliphatic or aromatic hydrocarbon radical, are prepared by dehydrogenating a cyclic alcohol of the general formula II ##STR2## or a cyclic ketone of the general formula III ##STR3## where one of the broken lines can be an additional C-C bond, in the gas phase at from 150.degree. to 380.degree. C. over a supported noble metal catalyst, by a process in which the dehydrogenation catalyst used is palladium or platinum on an aluminum spinel carrier, in particular an aluminum spinel which has a BET specific surface area of from 5 to 150 m.sup.2 /g or, for the dehydrogenation of cyclohexenones, preferably from 10 to 50 m.sup.2 /g. Particularly suitable aluminum spinels are those which, in addition to aluminum, contain magnesium, zinc, cobalt or nickel. In the novel process, substituted phenols are obtained in high yields and selectivities, and the catalyst has an extremely long life without a significant decrease in activity.
通式I的取代酚##STR1##其中R.sup.1、R.sup.2、R.sup.3、R.sup.4和R.sup.5分别为氢或脂肪或芳香烃基,通过在气相中,在150°C至380°C之间的温度下,通过在支持的贵金属催化剂上脱氢环状醇通式II##STR2##或环状酮通式III##STR3##其中其中一条虚线可以是额外的C-C键,制备的过程中,使用的脱氢催化剂为钯或铂载于氧化铝尖晶石载体,特别是具有BET比表面积为5至150m^2/g的氧化铝尖晶石,或者对于环己烯酮的脱氢,最好是10至50m^2/g。特别适合的氧化铝尖晶石是那些除铝外还含有镁、锌、钴或镍的氧化铝尖晶石。在新工艺中,取代酚以高产率和选择性获得,并且催化剂具有极长的寿命而无显著活性下降。