Reflux-recycle-reactor for high yield and selectivity in TAME and TAEE production

The batch reflux–recycle–reactor (RRR) proposed here was shown to give high product yields and selectivities in the production of tert‐ethers. Because the vapor pressures of product ethers are lower than those of the reactants, vapor‐phase reactor inlet stream is always rich in reactants in this batch RRR. A first‐order reversible reaction rate model was shown to give good prediction of experimental results. The apparent activation energy of the rate constant was evaluated as 24.8 kJ mol−1. This low value of activation energy for vapor‐phase synthesis of tert‐amyl methyl ether (TAME) was concluded to be primarily attributed to the significance of transport resistances in the macropores of Amberlyst‐15 and also through the thin liquid film covering catalyst particles. In the case of TAME production fractional conversion values reaching 0.91 were obtained at 82°C with almost 100% selectivity. Comparison of the results obtained for TAME and tert‐amyl ethyl ether (TAEE) synthesis showed that reactivity of methanol was much higher than that of ethanol in the etherification reaction of isoamylene, over Amberlyst‐15. © 2005 American Institute of Chemical Engineers AIChE J, 51:631–640, 2005