Preparation Of Grafted Hyperbranched Amine Adsorption Membrane And Its Removal Of Pollutants In Water

Membrane separation technology has a wide range of practical applications in the treatment of water bodies,especially wastewater treatment.Adsorption membranes,as a kind of separation membrane material,are a combination of separation membrane and adsorption.The adsorption film uses a membrane material having a certain pore diameter as a matrix or a medium to embed/attach a particle or a group having a target function to the membrane to have both membrane separation and adsorption capabilities.The membrane material has excellent performance and is widely used.In recent years,the modification of membrane materials has been a research hotspot.The hyperbranched polyamide-amine(HPAMAM)used herein has a special hyperbranched structure and a large number of terminal amine groups,and they have similar properties compared to dendrimers with a highly symmetrical structure,but HPAMAM The preparation method is simpler and more convenient,and the production cost is lower.Therefore,it has a good prospect in the field of membrane modification.In this paper,the homobranched amine was successfully grafted onto the cellulose material by means of interfacial polymerization and chemical grafting with isophthalic acid chloride as the crosslinking agent.After the preliminary comparison of the two methods,the chemical grafting method was selected.The HPAMAM modified adsorption membrane was prepared by the method.The adsorption capacity of the modified membrane for copper ion,chromium ion,lead ion,methyl orange and rhodamine B was determined.The influence factors such as pH value,concentration and time on the adsorption capacity were tested.Influence and study of its adsorption isotherms and adsorption kinetics models.It was found that the HPAMAM modified cellulose adsorption membrane has good adsorption capacity for three heavy metal ions and two dyes,but the fiber strength of the filter itself is not high,and the repeated use performance is poor.In this paper,a pure cotton filter cloth with high fiber strength was selected as the base film,and the hyperbranched amine was successfully grafted on the filter cloth.The adsorption capacity of copper ion,methyl orange and rhodamine B was tested,and the influence of pH,concentration and time on the adsorption capacity was examined.It was found that HPAMAM modified cellulose adsorption membrane has good adsorption capacity for three heavy metal ions and two dyes,and its adsorption isotherm and adsorption kinetics model were studied.It was found that the HPAMAM modified filter cloth has good adsorption capacity for copper ions and two dyes,and the adsorption capacity is larger than that of HPAMAM modified cellulose adsorption membrane,and the recyclability is good.Adsorption capacity still retains 70%after repeated use for four times.