| Poly (phthalazinone ether sulfone ketone) is a novel membrane material with high glass-transition temperature, good solubility, well membrane-forming ability, good mechanical performance and chemical stability. In this work, the preparation and the hydrophobic modification of PPESK hollow fiber membrane were investigated. Furthermore, soy sauce treatment by UF and chlorophenol removal by vacuum membrane distillation were studied.Hollow fiber ultratiltration membranes were prepared successfully from poly(phthalazinone ether sulfone ketone) (PPESK) with a dry/wet phase inversion technique. Poly(vinyl pyrrolidone) (PVP) was used as additive. N-methyl-2-pyrrolidone (NMP) and N,N-dimethylacetamide (DMAc) were used as solvents in membrane preparation. The effect of PVP concentration on the thermodynamic stability and the viscosity of the casting system was studied and the effects of the factors, such as the type of solvents, the PPESK concentration, the concentration of additive in casting solution on the morphology and performance of hollow fiber ultratiltration membranes were systematically investigated respectively. The results showed that the addition of PVP decreased the thermodynamic stability and increased the viscosity of the casting system and further more affect the structure and performance of hollow fiber membranes. The effect of hypochlorite treatment was also investiged and found that the hypochlorite treatment could decompose PVP. Furthermore, the pore size of the treated membranes could be altered after this treatment, and as a result the PPESK membranes show high flux, high porosity and low rejection. At the same time, the chemical stability of PPESK hollow fiber was studied and found the PPESK hollow fiber showed excellent acid-resistant ability, alkali-resistant ability and chlorine-resistant ability.The removal bacterial from soy sauce using PPESK hollow fiber membrane was investiged. The influence of operation parameters on the membrane performance and the washing methods were discussed. The results showed that the bacterial could be removed from soy sause with 100 percent. The permeate flux decreased unsignificantly in 27h operationg time. The permeat flux recovery rate of steam-washing and chemical back-washing could reach to 100%.The effects of PPESK hollow fiber membrane modification with three materials: siliconerubber, fluororubber and polytrifluoropropylsiloxane were investigated, respectively. The results showed that the PPESK hollow fiber membrane became hydrophobic after modified and the contact angle with water and the entry press of water of PPESK hollow fiber membranes increased. The permeat flux and the rejection of silicone rubber coated membrane were 3.3L·m-2·h-1 and 99% for for 5g/L NaCl solution respectively. The performance of silicone rubber coated membrane was stable in 15 days operation. For fluororruber coated membrane, the permeat flux was 3.1L·m-2·h-1 and the rejection was 98%. However, the rejection decreased significantly with operating time. The permeat flux was 3.7 and the rejection was 94.6% for polytrifluoropropylsiloxane coated membrane. And the the rejection decreased significantly after 11 days.The hydrophobic PPESK hollow fiber membrane was used to remove chlorophenol by VMD method. The mass transfer coefficient and removal fector is calculated for expressing the remove ability and remove efficiency. The result showed that the VMD method can well removed tnchlorophenol from water. The transfer coefficient increased and the removal fector kept constant with operating pressure. The transfer coefficient increased and the removal fector decreased with operating temperature.The PVDF/PPESK hollow fiber alloy membrane was prepared for improving mechanical performance and adjusting pore size. The influences of compatibility, concentration of polymer, kind or concentration of additive were investigated. The results showed that 18:1 and 18:2 were better ratio for PVDF and PPESK. The permeate flux of alloy membrane was 10.70 L·m-2·h-1 at 0.01MPa. The rejections for 5g/L NaCl solution were 99%. At the same time, the alloy membrane was applied on removing chlorophenol by vacuum membrane distillation and the removal ratio was 39% in 1h operation and at 40℃.
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