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Hybrid processes combining a polymer membrane and photocatalyst have received continual worldwide research attention,but ceramic membranes with excellent performance have not been tested for this application because of their high cost.Bellobono et al.[1] researched the advanced oxidation and integral photodegradation of organics in potable and wastewaters by membranes immobilizing titanium dioxide and promoting photocatalysts.Molinari et al.[2] described different flowsheets of photocatalytic membrane reactors for degradation of organic pollutants in water.Azrague et al.[3] described the combination of a dialysis membrane and a photochemical reactor into a membrane photoreactor (MPR) for the mineralization of organic pollutants from turbid effluents.Pidou et al.[4] investigated fouling control of a membrane-coupled photocatalytic process treating greywater.However,a ceramic membrane was not considered,despite its excellent performance,because of its high cost.The N2 back-flushing period (FT) and time (BT) were investigated in hybrid process of tubular ceramic microfiltration (MF) and polyethersulfone (PES) beads loaded with titanium dioxide (TiO2) photocatalyst for advanced drinking water treatment in viewpoints of membrane fouling resistance (Rf),permeate flux (J),and total permeate volume (VT).As decreasing FT and increasing BT,Rf decreased and J increased,and finally the maximum VT could be acquired at FT 10 min and BT 30 sec.In FT effect experiment,treatment efficiencies of turbidity and dissolved organic matters (DOM) were the highest at no back-flushing (NBF) because of dramatic membrane fouling.As result of BT effect,the treatment efficiencies were the maximum at BT 30 sec,which was different with the FT result.Because the photocatalyst beads could be cleaned effectively as decreasing FT and increasing BT,turbidity treatment efficiency increased a little from 95.4% to 97.5% as decreasing FT,and from 95.9% to 98.5% as increasing BT.Also DOM treatment efficiency increased from 70.8% to 80.6% as decreasing FT,and from 75.1% to 85.8% as increasing BT.The optimal condition,where the treatment efficiencies and VT were the maximum,should be FT 10 min and BT 30 sec in our experimental range.Also,we studied pH effect on the hybrid process of tubular ceramic MF and PES beads loaded with TiO2 in the pH range of 5~9.In this pH range Rf decreased and J increased as pH rising.As results,the final Rf,after 180 minutes’ operation was the minimum and the final J was the maximum,and the largest VT was absolutely 7.63 L at pH 9.Because the ceramic membrane surface was positive charged and humic acid was negative at acid condition of pH < 7,membrane fouling could have formed severely on the membrane surface.However,the ceramic membrane surface was changed to negative charge at alkali condition of pH > 7,and membrane fouling could be dropped dramatically.The turbidity treatment efficiency was almost same as 98.7~99.0%,but the DOM treatment efficiency decreased as pH increasing and finally was the maximum 84.5% as pH 5.The reason of this result was that adsorption rate of humic acid on PES beads increased because TiO2 particle surface of PES beads was positive at low pH,which was agreed with Kim’s result [5].