Alginate is a natural polysaccharide polymer.Hydrogel filtration membranes prepared from alginate show excellent fouling resistance and controllable separation performance,but poor mechanical properties limit the use ...Alginate is a natural polysaccharide polymer.Hydrogel filtration membranes prepared from alginate show excellent fouling resistance and controllable separation performance,but poor mechanical properties limit the use of algae hydrogels.In this study,Ba^(2+)/Ca^(2+)co-crosslinked alginate(Ba/CaAlg)hydrogel membrane was prepared by cross-linking sodium alginate with a blend aqueous solution of barium ions and calcium ions,and the membrane was applied to the separation of dyes/salts from dyeing wastewater.Compared with the CaAlg membrane,the Ba/CaAlg hydrogel membrane exhibited more stable structure,and the mechanical properties and salt tolerance of the membrane were significantly improved.The flux of Ba/CaAlg membrane for methyl blue/sodium chloride mixed solution reached 43.5 L m^(−2) h^(−1),which was significantly higher than that of CaAlg membrane.Besides,the Ba/CaAlg membrane showed higher dye rejection(>99.6%)and lower salt rejection(<8.2%).The structure of Ba/CaAlg membrane was preliminarily simulated by molecular dynamics,and the pore size and distribution of the membrane were calculated.The Ba/CaAlg membrane has a broad application prospect in dyes/salts separation.展开更多
基金supported by the National Natural Science Foundation of China(No.22078244)Scientific research and development project of SINOPEC(No.222443)the Science and Technology Plans of Tianjin(No.20JCYBJC00120).
文摘Alginate is a natural polysaccharide polymer.Hydrogel filtration membranes prepared from alginate show excellent fouling resistance and controllable separation performance,but poor mechanical properties limit the use of algae hydrogels.In this study,Ba^(2+)/Ca^(2+)co-crosslinked alginate(Ba/CaAlg)hydrogel membrane was prepared by cross-linking sodium alginate with a blend aqueous solution of barium ions and calcium ions,and the membrane was applied to the separation of dyes/salts from dyeing wastewater.Compared with the CaAlg membrane,the Ba/CaAlg hydrogel membrane exhibited more stable structure,and the mechanical properties and salt tolerance of the membrane were significantly improved.The flux of Ba/CaAlg membrane for methyl blue/sodium chloride mixed solution reached 43.5 L m^(−2) h^(−1),which was significantly higher than that of CaAlg membrane.Besides,the Ba/CaAlg membrane showed higher dye rejection(>99.6%)and lower salt rejection(<8.2%).The structure of Ba/CaAlg membrane was preliminarily simulated by molecular dynamics,and the pore size and distribution of the membrane were calculated.The Ba/CaAlg membrane has a broad application prospect in dyes/salts separation.