Zeolite-catalysed liquid-phase synthesis of isopropyl tert-butyl ether by the addition of 2-propanol to isobutene

The paper deals with the liquid-phase synthesis of isopropyl tert-butyl ether (IPTBE) from 2-propanol and isobutene over H-Beta, H-ZSM-5, and H-Y zeolites. The SiO2/Al2O3 ratio of tested zeolites was about 25 for H-Beta, 28 for H-ZSM-5, and 6 for H-Y. Experiments were performed in a batch reactor in the temperature range of 70–90 °C at 1.6 MPa. A comparative study of the behaviour of these catalysts was made at 80 °C by with an initial alcohol-to-isobutene molar ratio (image) of 1. We optimised the activation process of the three zeolites by varying the temperature and time of calcination, thus selecting the experimental conditions of activation leading to the highest activity and selectivity. H-Beta was the most active and selective catalyst. Therefore, the kinetics of IPTBE synthesis was studied on H-Beta in the temperature range of 70–90 °C, with a image varying from 0.7 to 2. The best kinetic model stems from a mechanism in which isobutene reacts with 2-propanol, with both adsorbed on one site, to give the ether adsorbed on one site. The apparent activation energy was estimated to be image.