Distillation of methanol–water solution in hollow fibers

Non-porous hollow fibers were used as more excellent structured packing over normal packing in the distillation of methanol–water system. Due to their special geometry, a column with hollow fibers could easily work 3–10 times higher above the limit where flooding usually occurs in conventional cases. A small height of transfer units at 8 cm and the overall mass-transfer coefficient Kx based on the liquid-side at 2.3 × 10−5 mol/cm2 s were obtained experimentally. Compared with theoretical estimation from earlier studies, it was found that the liquid side was mostly responsible for the total resistance of mass transfer, which was similar to the conventional distillation process at low concentration, although mass transfer resistance in the membrane and the vapor could not be negligible.