Study On The Preparation And Functionalization Of Acrylic Polymer/graphene Oxide Composite Fiber

Dyes wastewater has become one of the main sources to cause the pollution of environmental water;thus,it is urgent and necessary to treat dyes wastewater effectively.Fenton method is very convenient for treating dyes wastewater;thus,it has attracted extensive attention of scholars.Under these backgrounds,we attempted to fabricate newly functional fiber to expand the application of fiber in the field of treating dye wastewater by Fenton method.When benzoyl peroxide was chosen as initiator,the copolymer of acrylic acid(AA)and hydroxyethyl methacrylate(HEMA)was first synthesized via precipitation polymerization with AA and HEMA being used as monomers,and a dilute solution of sodium hydroxide was then used as a solvent to prepare the spinning solution.Polyethylenimine(PEI)and graphene oxide(GO)were introduced into the spinning solution to improve the self-supportability of the copolymer of acrylic acid and hydroxyethyl methacrylate during fiber formation,along with the capability of fiber to load iron ions.The corresponding fiber was prepared by using a dilute aqueous solution of sulfuric acid as a coagulation medium through wet spinning.The fibrous heterogeneous Fenton catalyst was prepared via simple impregnation by using the fiber prepared above as a carrier.The results showed that the self-supportability of the copolymer was effectively improved due to the co-modification of PEI and GO,and the obtained fiber had a nearly-circular structure instead of the flat structure.The fibrous catalyst could catalyze hydrogen peroxide to decolorize MB aqueous solution within 7 minutes during the first eight cycles,and the decolorization efficiency of MB was higher than 94%;additionally,the TOC value of MB aqueous solution obtained at the eighth cycle was measured to be 8.7 mg/L,which was still less than 10.9 mg/L of original solution.PEI was easily dissolved in water during the initial period,and its dissolution would affect the TOC of the treated water.What was more,PEI combined with the copolymer to form a salt,and some carboxyl groups were consumed,thus,it would decrease the iron ions loading ratio.Therefore,a fibrous catalyst with better performance is prepared with GO being used as a single filler by adopting a crosslinking process.The optimum GO addition amount,loading time,andcrosslinking condition were determined by researching the application performance of corresponding fiber.The iron ions loading ratio of fiber was greatly increased by optimizing GO dosage and loading time while the construction of cross-linked structure could effectively prohibit the leaching-out of iron ions,making the prepared fibrous catalyst have more prominent catalytic performance.In order to further improve the application performance of the obtained fibrous catalyst,the parameters such as drying method,drying time,and drying temperature that were involved in the post-treatment process were optimized,and the morphology,crystalline state,chemical structure,and reusability of the fibrous catalyst obtained after the above optimization were characterized.The results showed that a large number of active substances were immobilized onto the body and surface of the fibrous catalyst prepared via the optimum processes.In addition,due to the slow leaching-out of iron ions,the fibrous catalyst could catalyze hydrogen peroxide to decolorize MB aqueous solution within 3 minutes during the first eleven cycles,with the decolorization efficiency higher than 94%,and it could still decolorize 93.33% of MB within 90 min when it was used for the thirteenth time.