Process configurations for the production of the 2-methoxy-2,4,4-trimethylpentane - a novel gasoline oxygenate

A comparison of various process configurations was made for the production of 2-methoxy-2,4,4-trimethylpentane, which is a promising gasoline component owing low solubility to water and high octane value. The ether is synthesised by reacting methanol with a mixture of 2,4,4-trimethyl-1-pentene and 2,4,4-trimethyl-2-pentene, which are obtained in large scale from the dimerisation of isobutene. The reaction equilibria were determined experimentally at temperature range 323-383 K in liquid phase using a commercial cation exchange resin Amberlyst 35 as catalyst. A first order kinetic model was developed and utilised in the process simulations. The production of the ether was found to be inefficient in a once through tubular reactor, because the conversion is strongly limited by the reaction equilibrium. Considerably higher conversion and more economical process are obtained by using reactive distillation in the process schema. (C) 2002 Elsevier Science B.V. All rights reserved.