| Membrane filtration is widely used in water treatment.However,membrane fouling is a key limitation factor for membrane filtration performance,efficiency and economic viability.Photo-Fenton reaction is one of the Advanced oxidation processes(AOPs),which is green technology and environmently friendly.Besides,the Photo-Fenton reaction has a low operation cost and a high degradation efficiencies.However the catalysts in the Photo-Fenton reactions still have the problem of blocking the membrane pores or difficult recycling.In order to overcome thess problems,a new Photo-Fenton Reactive Ceramic Membrane was made by combining membrane separation with photo degradation.The hydroxyl radical(-OH)precede by the Photo-Fenton reaction was used to degrade the organic pollutants.By this way,the quality of the efflutent was improved and the membrane fouling was effectively slowed down even prevented at the same time.So the Photo-Fenton Reactive ceramic membrane was coated in the article by hybridization method,and its synthesis control?characterization and performance abilities were analysed by different detective methods.The batch reaction and continue reaction were conducted with the coated membranes.A photo-electronics banlance model was built to compare the level of the electron loading from the influent pollutant(Je)and the maximum possible capacity of electron transfer rate(JP).The natral pollutants and antibiotic compound were used as goal pollutants to study the membrane filtration ability and stable ability on different VU intensity?coating catalyst amount and hydrogen peroxide concentration.And the degradation mechanism and pathways were studied as well.The conclusions are showed below:1)The hybridization method was chosen to coat the a-FeOOH catalyst on the surface of the ceramic membrane.The stablilty and catalytic performance of the modified membrane were studied.The influences of the coating amount,density and porosity on surface properties(e.g.,morphology,flux resistance)were also analyzed.The modified ceramic membrane had a big filtration flux and great catalytic ablitly with the Rf value of 2.74 ×1010m-1.2)Study on the antifouling and degradation of the modified ceramic membrane under natural organic pollutants.The BSA and HA were used as goal pollutants standing for the natural organic pollutant to study the TMP on different operation conditions.The removel rates of BSA and HA were 90%?38%and 80%?50%under the condition of modified ceramic membrane+ UV + H2O2 and modified ceramic membrane+UV within 60 minutes.The fouling mechanism was analysed by the blocking model,which indicated the membrane may undergo complete pore blocking,and the fouling was reversible.After chemical cleaning with NaOH solution and phosphoric acid,the membrane flux recovered to the DI water flux level.3)Study on the degradation and pathways by the modified ceramic membrane with two model antibiotic compounds,sulfadiazine(SDZ)and sulfamethoxazole(SMX).They were used to analyse the removal efficiency under different photo-Fenton reaction conditions.The first-order rate constants of the SDZ and SMX under the modified ceramic membrane + UV + H2O2 condition were 1.0969 and 1.01 in batch experiment.The mediam coating membrane could reach a good SDZ degradation with the catalyst on the ceramic membrane 2?g·g-1;The degradation of SDZ and SMX could increase with the UV intensity as well as the AQY when the UV intensity was lower than 200?W·cm-2.Four main byproducts and four possible degradation pathways for SDZ were inferred by LC-ESI-MS results,together with nine main byproducts and three possible degradation pathways for SMX.4)The photo-electronic model was set up to investigate the relationship among the influent concentration?flow rate and apparent quantum yield.Based on this,the removel efficiency of SDZ and SMX were studied as well as TOC.The modified caremic membrane improvd the removel efficiency of SDZ and SMX by 10%and 8%separately compared to the origin ceramic membrane.The influent concentrations had a big effect on the TMP.The TMP increased quickly when the influent pollutant(Je)was bigger than the maximum possible capacity of electron transfer rate(Jp).So the Je should be less than the Jp in experiment process.The SDZ removal ratio remained near 100%after 10 consecutive cycles of repeated use,highlighting its excellent stability and photocatalytic activity. |
PDF Full Text Request