| 摘要 |
<p>polyalkylbenzenes are dehydrogenated by (a) passing with steam over a steam-regenerable dehydrogenation catalyst for 10 to 60 secs. (pref. 20 to 45 secs.); (b) regenerating the catalyst under regeneration conditions for a period of 1.25 to 5.0 x (pref. 2 to 4 x) the reaction period, and (c) repeating (a). The polyalkylbenzenes are diisopropyl, diethyl or ethylisopropyl, and are dehydrogenated at a partial pressure of 0.01 to 0.15 (pref. 0.05 to 0.07) atm. over a catalyst of Fe2O3-Cr2O3-K2CO3 at 800 to 1200 (pref. 975 to 1125) degrees F and 0.1 to 1 (pref. 0.15 to 0.35) secs. residence time. The use of the short cycle dehydrogenation/regeneration system with the time ratios specified enables the initial activity of a regenerable dehydrogenation catalyst to be maintained.</p> |
