Study On The Adsorption Property Of Modified Cotton Fibers To Heavy Metal Ions

Heavy metal pollution is caused by the heavy metals or their compounds.After itenters the human body through food and water,this can occur strong interaction withproteins and various enzymes,making them lose their activity;they may also enriched incertain organs of the human body,overdose can cause acute poisoning,subacutepoisoning,chronic poisoning and so on,this will have great harm to human bodys.Therefore,treatment of heavy metal pollution has attracted people’s attention.This topic take cotton fibers as a carrier,successfully prepared two modified cottonfiber adsorbent by grafted tetraethylenepentamine monomer and HBP-NH2to oxidizedcotton fibers,at the same time we optimized its preparation process.The morphology andstructure of modified cotton fiber were analyzed by scanning electron microscopy (SEM)and infrared spectroscopy (FT-IR).The results showed that:After modified,the longitudinalstripes in the surface of pretreated cotton fiber disappeared;there containing a large numberof amino and hydroxyl active sites on the prepared adsorbents molecules,they can adsorbeand remove heavy metals by Chelating ligands with heavy metals ions.The adsorption of HBP-NH2modified cotton fiber adsorbent is better thantetraethylenepentamine monomer modified cotton fiber adsorbent.The maximumadsorption of Pb2+,Cd2+,Cu2+by HBP-NH2modified cotton fiber adsorbent can reached41.38mg/g,28.91mg/g,19.16mg/g.This paper discusses the influence of the adsorbent dosage,pH,adsorption of time,initial concentration of metal and other conditions on the adsorption effect.To have a betterunderstanding of the adsorption behavior for heavy metal ions,we use adsorption kineticsand adsorption isotherms to fit the experimental data and then analysis.Kinetic experimentsshowed that:Quasi-two equations is more suitable to describe the adsorption process,andthe adsorbents have a higher adsorption rate of the three metal ions,they can achieveadsorption equilibrium within2h.Adsorption isotherm results indicate that:Langmuir isbest suited to describe the adsorption process for heavy metal ions,which is monolayer adsorption,and the adsorption sites of the adsorbent surface distributed more evenly.