Feasibility Study on the Etherification of Fermentative-Produced Isobutylene to Fully Renewable Ethyl <em>Tert</em>-Butyl Ether (ETBE)

Abstract

This work evaluates the direct etherification of bio-sourced isobutylene with ethanol forming fully renewable ethyl tert-butyl ether (ETBE). Challenge was the use of the fermentative produced substrate in a solvent-free catalysis using the acidic ion exchanger Amberlyst-15. CO2 impurities have a significant influence on the liquid phase process. The conversion at a ratio that is based on molarities of isobutylene to ethanol of 1:0.9 results in yields up to 97 mol% ETBE. Purities up to 99 wt.% could be achieved by subsequent water extraction in order to ensure qualities for technical application as high performance fuel additive.

Keywords

• ethyl <i>tert</i>-butyl ether (ETBE)
• biofuel additive
• bio-sourced isobutylene
• etherification
• Amberlyst-15