Preparation Of Poly(meth)acrylate-based Fibrous Materials And Their Catalytic Properties For Oxidative Decomposition Of H2O2/O3

Advanced oxidation process is considered as an effective method to treat dye wastewater.Powdered or granular manganese oxides have been used as catalysts in advanced oxidation process;however,powdered or granular manganese oxides exhibit a single shape,they can't be directly taken out from water after application,and filtration or centrifugation process is often adopted to separate these particles from water,thus application cost increases greatly.The materials which are prepared by loading manganese oxides on the surfaces of fibrous materials can be applied in the field of dye wastewater treatment,and these materials not only can solve the problem that granular or powdered manganese oxides can't be directly taken out from waterafter application but also can be recycled and reused,thus the cost reduces significantly.Methacrylate or acrylate polymer has excellent fiberizability,and has been used to treat dye wastewater,therefore,the combination of manganese oxides with(meth)acrylate polymer fiber is expected to play a positive role in the field of dye wastewater treatment.In this paper,butyl methacrylate(BMA)and hydroxyl ethyl methacrylate(HEMA)were used as monomers,benzoyl peroxide(BPO)was used as initiator,and N,N-dimethyl formamide(DMF)was used as solvent,the solution of the copolymer of BMA and HEMA(P(BMA-co-HEMA))was synthesized via solution polymerization.The copolymer solution obtained above was used as spinning solution,and solid and hollow fibers were prepared via wet spinning.The chemical structure of copolymer was analyzed by using fourier transform infrared spectrometer(FTIR)and nuclear magnetic resonance spectrometer(1H-NMR)and the morphology of the obtained fiber was observed by using field emission scanning electron microscope(FESEM).Under alkaline condition,the hydroxyl groups on the surface of the fiber were oxidized into carboxylic acid groups,and potassium permanganate was reduced to manganese oxides through an oxidation-reduction reaction.The generated manganese oxides were firmly loaded on the surface of the fiber via the complexation between carboxylic acid groups and manganese oxides.Manganese oxides-loaded fiber was used to catalyze hydrogen peroxide and ozone to oxidize model dyes.The results showed that when the solid fiber prepared with a mass feed ratio of BMA and HEMA of 6:4 and a post-treatment time of 3h was used as a catalyst,the removal efficiency of cationic blue could reach 93.6%within 210min.While the hollow fiber prepared with a mass feed ratio of BMA and HEMA of 6:4 and a post-treatment time of 30min was used as a catalyst,the removal efficiency of cationic blue could reach 94.2%within 90min.It could be seen that hollow fiber had application advantage over solid fiber.However,the hollow fiber prepared with a mass feed ratio of BMA and HEMA of 6:4 exhibited poor flexibility.In order to improve the flexibility of the hollow fiber,the solution of the copolymer of butyl acrylate(BA)and HEMA(P(BA-co-HEMA))was synthesized via solution polymerizationand was introduced into the spinning solution which was composed of P(BMA-co-HEMA)and DMF.The bi-constituent hollow fiber with excellent hollow shape retention and flexibility was prepared,and the manganese oxides were then loaded on the inner and outer surfaces of the hollow fiber.The surface morphology,the type and composition of manganese oxides,applicability,and reusability were analyzed,along with the catalytic mechanism.The results showed that when the polymerization time was 2.5h,the volume ratio of P(BMA-co-HEMA)and P(BA-co-HEMA)solutions was 85:15,the post-treatment time was 30min,0.5ml H2O2 was added,and O3 was blown into 10ml cationic blue solution with a concentration of 20mg/l for 60s,the removal efficiency of cationic blue could reach 95.1%within 90min.In addition to cationic blue,the above system had good catalytic activity for the oxidative decomposition of a variety of dyes.The hollow fiber exhibited good reusability at several application modes,especially it could act as a channel for the water containing dyes,thus the real-time processing of the water containing dyes could be achieved.