Study On Preparation Of Graft Copolymerization Flocculant Based On Lignosulfonate

The flocculation is a important methods in water treatment technology, the primary problem of flocculation is that the flocculant was preparation with excellent performance and reasonable price, and broad-spectrum.In the paper industry lignosulfonate was one of the main pollutants, The pollutants of 50% is lignosulfonate in papermaking Wastewater of the traditional sulfite. In recent years, polymer flocculant as the substrate of biomass was much attention to development and application. Because of the requirements were from the energy crisis, environmental protection and sustainable development.In the paper, I made a universal and good flocculant by graft copolymer modified as a raw material of lignosulfonate.A lignosulfonate flocculant(LA) was synthesized by copolymerization of lignosulfonate and acrylamide(AM). The Copolymerization conditions copolymerization of lignosulfonate and acrylamide(AM) was investigated. and it was used to flocculation landfill leachate. The flocculation of landfill leachate showed that the composite flocculants were better of modified lignosulfonate and polymerizationFeC13. COD removal was 76%, the floeculant can still hold the good floceulation effieieney under the operating conditions of high temperature.A lignosulfonate amphoteric flocculant(LDA) was synthesized by copolymerization of lignosulfonate with acrylamide(AM) and diallyl dimethyl ammonium chloride (DMDAAC). The optimum reaction conditions were obtained as follows:reaction temperature is 50?,copolymerization time is 6h, solid content is 20%,initiator concentration is 0.1%, mass ratio of monomer to lignosulfonate is 4:1, mass ratio of acrylamide to diallyl dimethyl ammonium chloride is 2:1.The limiting viscosity of LDA was 635.2ml/g,the grafting efficiency was 99.2%,cationic degree was 26.8%.The structure was confirmed by IR,1H-NMR and SEM. And four kinds of wastewater was treated,COD was up to the standards. And the results showed that the floeculant can still hold the good floceulation effieieney under the operating conditions of high temperature, high salt, sulfuric acid and strong base.