ISOPROPYLATION OF BENZENE WITH 2-PROPANOL OVER HIGH-SILICA LARGE-POREZEOLITE - NCL-1

The influence of various reaction parameters such as temperature, WHSV , time on stream, and feed ratio of benzene to 2-propanol, as well as of the Si/Al molar ratio of zeolite NCL-1, on catalytic activity and s electivity was studied in the isopropylation of benzene with 2-propano l. The selectivity towards cumene increases with Al content, contact t ime, and ratio of benzene to 2-propanol. Among diisopropylbenzenes (DI PBS), the concentration of 1,3-DIPB (vis-g-vis 1,4-DIPB) increases wit h increases in reaction temperature, Al content of the catalyst, and b enzene conversion. The 1,2-DIPB, with relatively high strain energy (4 .26 kcal mol(-1)) compared to that of either 1,3-DIPB (2.02 kcal mol(- 1)) or 1,4-DIPB (2.78 kcal mol(-1)), was formed in very small quantiti es (0-2 wt%). (C) 1995 Academic Press, Inc.