PERVAPORATION SEPARATION OF METANOL FROM METHYL t-BUTYL ETHER WITH POLYHIDROXYBUTYRATE (PHB) MEMBRANE

MERCEDES VILLEGAS; ELZA F. CASTRO VIDAURRE; JUAN C. GOTTIFREDI

Cancún

Congreso; XIII International Materials Research Congress; 2004

Academia Mexicana de Ciencias de Materiales

<< El trabajo enviado era en forma de Resumen. La presentación fue modalidad Oral por lo que se adjunta nuevamente copia de este Resumen >>  Tertiary ethers have attracted much attention as octane boosters, due to their pollution reduction and excellent blending capabilities. Methyl t-butyl ether (MTBE) is one of them. It is produced by reacting isobutene with methanol (MeOH) in excess, and the unreacted MeOH is subsequently distilled off and recovered. This distillation process is energy intensive as MeOH – MTBE is an azeotropic mixture. Pervaproation (PV) is a membrane-based separation process. This technique has attracted recent interest because it is potentially less energy-intensive than distillation. The final application of pervaproation membranes is the separation of organic solvent mixtures. Currently this is the least development application of pervaporation. In this study, sorption and transport properties of alcohol and ether through films of PHB were obtained. A Cahan electrobalance was employed for measuring the solvent uptake by the polymer samples. The pervaporation characteristics of a PHB membrane with MeOH-MTBE mixtures were investigated at a feed temperature of 40ºC and a feed composition of 17% in MeOH, and measuring quantities such as flux and selectivity. This membrane was found to be highly methanol selective, with the separation factor of 5.5, and a flux of 315 g cm-2 h-1. It was finally ahown that pervaporation can easily be used to break the azeotrope of meOH-MTBE, and that the membrane shows potential for being used in an industrial hybrid distillation-PV system.