| The effective recycling and reuse of organic compounds have always been an indispensable part in wastewater treatment realm,the membrane separation techniques of treating industrial wastewater had been utilized on many application realms. Poly(phthalazinone ether sulfone ketone)(PPESK) is a novel membrane material for filtration membrane with high glass-transition temperature,good solubility,good mechanical performance and chemical stability,in this thesis a series of different membranes were made by PPESK material and were used to separate and concentrate a water sample containing sulfolanc and inorganic salts.This research provided a good reference of membrane separation wastewater treatment in similar solution system.A series of poly(phthalazinone ether sulfone ketone) composite membranes were prepared by piperazine(PIP) and m-phenylenediamine(MPD) with trimesoylchloride(TMC) respectively through the interfacial polymerization technique on the poly(phthalazinone ether sulfone ether ketone)(PPESK) supporting membrane.The effect of the structure of substrate membrane,the content of monomer and the time of interfacial polymerization on the surface morphology and separation pcrformancc of the composite membrane were studied.A PPA/PPESK membrane with 96%rejection to 1g·L-1Na2SO4 solution and a PA/PPESK membrane with 94%rejection to 2g·L-1KCI solution were used to separate the sulfolane solution at 20℃and 1.0Mpa,the results showed that the rejections to the sulfolanc were respectively 64%and 84%,and the rejections to the salts solved in the solution were 72%and 90%,and the permeation flux were 16.8L·m-2·h-1 and 6.5L·m-2·h(-1).The PA/PPESK membrane had a better stability performance than the PPA/PPESK membrane when dipped into the 100 g·L-1 sulfolane solution with 90 day captive test.A flat membrane test device was used to simulate the two-stage separation and concentration process using PA/PPESK membrane.The permeate solution of the first stage entered the second stage as a feed.It turned out that the suitable concentration ratio of the two stage separation was separately 50%and 90%.Under the condition of 50℃and 1.5MPa,the PA/PPESK membrane was used to separate the 10 g·L-1 sulfolane solution,The result indicated that the contents of sulfolane in the two stage concentration solution were about 20g·L-1 and 18.5g·L-1 when the feed containing 10g·L-1 sulfolane and the conductivity was 2×103μS·cm-1,the second permeate had 0.2g·L-1 sulfolane content and the conductivity was 0.01×103μS·cm-1.The PA/PPESK membrane showed a good performance through a 24h constant separation opcration in the concentrated suifolane solution with a 20g·L-1 sulfolane content and 3×103μS·cm-1 conductivity. CMPPESK was acquired from PPESK through chloromethylation;CMPPESK asymmetric membrane was prepared form CMPPESK membrane material by phase inversion method. And quaternized poly(phthalazinone ether sulfone ketone)(QAPPESK) nanofiltration(NF) membranes were prepared from CMPPESK asymmetric membrane by quaternized modification.The effects of preparation conditions,such as the content and sorts of solvents and non-solvent additives,the concentration of polymer,the composition of quaternization reagent and the temperature of quaternization were investigated.QAPPESK NF membranes were obtained by optimal technology conditions,which had a rejection of 93%and 15L·m-2·h-1 permeation flux to the 1g·L-1 MgCl2 solution at 20℃and 0.4MPa.A series of QAPPESK NF membranes were used to separate the sulfolane solution,the effects of the operation temperaturc and pressure were investigated.A constant separation trial to the sulfolane solution procecded at 50℃and 1.0MPa,it was found that the rejection to the sulfolane was from 44%to 54%and the permcation flux was from 14.8L·m-2·h-1 to 14L·m-2·h-1 when the concentration ratio was 60%below.In this course the performance of membrane was stable.The long time separating pertormancc of the QAPPESK NF mcmbrane in the sulfolane solution needs to be researched further.
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