Study On Adsorption Properties Of Amino Modified Cotton Fiber Products

The pollution of dyes and heavy metal ions is increasingly serious,A large number of dye and heavy metal emissions have caused damage to the ecosystem,which has seriously affected human health and the sustainable development of society.Adsorption is a simple,low-cost and widely used method for pollutant removal.Among them,the preparation of highly efficient adsorption materials based on natural renewable cellulose conforms to the trend of green and sustainable development.In this study,the amino modified two-dimensional flexible adsorption products were prepared by green process with the cotton fabric as the framework,and the terminal amino hyperbranched polymer rich in amino as the functional active substance.Firstly,cotton fabric was activated and then selectively oxidized.Amino modified cotton fiber products with high adsorption performance were prepared by using self-generated dialdehyde group to graft amino hyperbranched polymer(HBP-NH2).The optimal conditions of selective oxidation process and grafting process were explored,the cotton fabrics before and after modification were characterized,the adsorption properties of dyes(kongo red,acid blue 9)and heavy metal ions(Pb2+,Cr6+,Cu2+)were tested,and the adsorption mechanism was analyzed.The results show that Cotton fabric is successfully grafted with HBP-NH2 to prepare amino modified cotton fabric,and it has good adsorption effect on dyes and heavy metal ions.The maximum adsorption capacity of amino modified cotton fabric to Congo Red and Acid Blue 9 is 248.73mg/g and 57.57mg/g respectively,which is 5?10 times higher than that of ordinary cotton fabric.The maximum adsorption capacity of Pb2+,Cr6+,Cu2+is 35.75mg/g,22.16mg/g and 19.95mg/g respectively,which is 20?23 times higher than that of ordinary cotton fabric.In order to better describe the adsorption performance of amino modified cotton fabric for dyes and heavy metal ions,the effects of adsorption material dosage,adsorption time,initial solution concentration and solution pH on adsorption performance were studied.The adsorption kinetics and isotherm model were used to fit the experimental data.The results show that the quasi-secondary adsorption kinetics model has a better fitting effect on dyes and heavy metal ions than the quasi-first-order adsorption kinetics model.Meanwhile,the adsorption process of dyes and heavy metal ions by amino modified cotton fabric can be fitted by Langmuir adsorption isotherm model.