Investigation Of Synthesis Of Isopropyltoluene With Toluene Over Zeolite Catalyst

In this paper, based on zeolite catalyst, the application and basic research on synthesis of isopropyltoluene is carried out.Based on an isothermal integral reactor (reactor dimension:Φ16×3mm, L 300 mm), the most suitable catalyst for the sythesis of isopropyltoluene was studied, and the best choice wasβzeolite catalyst by comparison of HZSM-5, HM, HY andβ. Vapor/liquid phase alkylation reaction of toluene and propylene/isopropyl alcohol were carried out overβzeolite catalyst, respectively. It was obtained that the liquid phase alkylation is superior to gas alkylation and alkylation of toluene with propylene is superior to alkylation of toluene and isopropyl alcohol.The standard heat of formation, free energy and heat capacity of isopropyltoluene were estimated by means of Benson's and Missena's group contribution. The thermodynamic analysis of synthesis process of isopropyltoluene and the calculations of equilibrium constants were carried out.Then the effects of temperature, toluene and propylene molar ratio and liquid space velocity on the alkylation reaction process (including conversion and selectivity) were investigated by means of the single-factor experimental method under a wide experiment range. And the orthogonal test design was employed to investigate the global effect of these factors mentioned above on the alkylation process and the suitable operating conditions were determined as follows:temperature of 220℃, toluene/propylene molar ratio of 8:1 and space velocity of 30 h-1. Under above conditions, the selectivity of isopropyltoluene could reach 97.69% and the selectivity of o-isopropyltoluene could be controlled at 4.99%.