ABSTRACT
The alkylation of phenol with 1-butanol has been carried out over HZSM-5 and HY zeolites in a fixed-bed reactor at atmospheric pressure, temperature range 230-265 °C, contact time between 10-30 Kg.s/mol, and 1-butanol-to-phenol molar ratio varying from 1 to 3.
Butylphenols were the main products together with smaller quantities of phenyl butyl ether. Under similar reaction conditions HY zeolite was twice as active than HZMS-5 zeolite, while the selectivity of the pentasil catalyst was higher than that observed for the faujasite zeolite. For both solids an outstanding para-selectivity was achieved which gave rise to a high p-alkylphenol production. Even though both zeolites show a high shape-selectivity property, a significant improvement in the para-selectivity was obtained for the HZSM-5 zeolite; the butylphenol production being at least four times higher. Furthermore, in each case, the acid sites strength seems to be responsible for the C-alkylation/O-alkylation ratio observed.
