PDMS复合膜回收酯化反应废水中的异丁醇

The esterification reaction of acetic acid and isobutanol produces isobutyl acetate, which generates a large amount of wastewater containing isobutanol. The conventional biochemical treatment is heavy and wastes resources. The effects of isobutanol concentration on the swelling degree and separation performance of polydimethylsiloxane (PDMS) membrane, the operating parameters of the pervaporation process and the effect of isobutyl acetate on the recovery of isobutanol by PDMS membrane were studied. The results show that with the isobutanol concentration increases from 1%(mass) to 3%(mass), the swelling degree of the PDMS membrane increases first and then stabilizes, the flux of isobutanol increases, and the separation factor is about 15. When the operating temperature increases from 30℃ to 60℃, the flux increases, the separation factor of isobutanol decreases, and the total apparent activation energy is 33.87 kJ/mol. With increase of the flow rate, the isobutanol flux is stability while the separation factor increases slightly. The trace amounts of isobutyl acetate can promote the recovery of isobutanol by the membrane. The recovery rate of isobutanol by PDMS membrane is greater than 94.0%, and the concentration of isobutanol in the retentate can be reduced to 0.1%(mass). The research results can provide a basis for PDMS composite membrane to treat low-concentration organic solvent wastewater.