Effects of Sorption Enhancement and Isobutene Formation on Etherification of Glycerol with tert-Butyl Alcohol in a Flow Reactor

Abstract

In the presented work, liquid phase etherification reaction of glycerol (G) with tert-butyl alcohol (TBA) was investigated in a continuous flow reactor using Amberlyst-15 (A-15) as the catalyst. Some experiments were also repeated in a batch reactor at autogenous pressure. Effects of feed composition, reaction temperature (70–110 °C), and reaction pressure (1–5 bar) on the product distribution were investigated. When flow reactor pressure was reduced from 5 to 1 bar, enhanced glycerol conversion and isobutene formation were observed. Conversion of glycerol reached 66% at 110 °C, at a space time of 18 s·g·cm–3. However, batch reactor results indicated glycerol conversion values over 90% with diether selectivity of about 36% at much longer reaction times, over 400 min. Results indicated significance of equilibrium limitations, which initiated the idea of performing sorption enhanced reaction experiments in the flow reactor using Zeolite 4A and 5A as water adsorbents. Results of these sorption enhanced react...