Dehydrating performance of commercial LTA zeolite membranes and application to fuel grade bio-ethanol production by hybrid distillation/vapor permeation process

The performance of commercial NaA zeolite membranes (Bussan Nanotech Research Institute Inc., Japan) was investigated for dehydration viability by vapor permeation (VP) to apply them to production of fuel grade ethanol. We carried out mainly two sub-projects: (1) the VP experiments with a large unit to determine the dehydration performance for elemental membranes and (2) the field test to produce fuel grade ethanol from fermented hydrous ethanol (5–10 wt.% ethanol content) through hybrid distillation/vapor permeation system in which the membrane modules were installed. The commercial NaA zeolite membranes exhibited sufficiently high dehydrating performance for economically feasible fluxes. It has been also verified that anhydrous ethanol (>99.7 wt.%) with an amount of 46 kg h−1 can be continuously produced with the commercial NaA zeolite membranes in a pilot plant. These results suggest that the commercial NaA zeolite membrane can be expected to be utilized in motor fuel ethanol production.