Abstract
A new type of polyvinylidene fluoride (PVDF)/polymethyl methacrylate (PMMA) hollow fiber membrane (HFM) with five bores was prepared. The effects of Polyvinylpyrrolidone (PVP), β-cyclodextrine (β-CD), Polyethylene Glycol (PEG) and Polysorbate 80 (Tween 80) and their combinations on the PVDF/PMMA five-bore HFMs were investigated. The performance and fouling characteristics of five-bore HFMs for dyeing wastewater treatment were evaluated. Results indicated that adding 5wt.% PVP could increase the porosity and water flux of the membrane but decrease the bovine serum albumin (BSA) rejection rate. Adding 5wt.% β-CD significantly improved the tensile and rejection of the HFMs without showing effect on the increase of water flux. The characteristic of the HFMs with different additives combinations proved that the mixture of 5wt.% PVP and 1wt.% β-CD obtained the best membrane performance, with a pure water flux of 427.9 L/ m2·h, a contact angle of 25°, and a rejection to bovine serum albumin (BSA) of 89.7%. The CODcr and UV254 removal rates of dyeing wastewater treatment were 61.10% and 50.41%, respectively. No breakage or leakage points were found after 120d operation showing the reliable mechanical properties. We set the operating flux to 55 L/m2·h and cross flow rate to 10% which can effectively control membrane fouling.
High flux and antifouling properties of negatively charged membrane for dyeing wastewater treatment by membrane distillation
