Study On Synthesis And Application Of Natural Macromolecule Chelator

Natural Starch is one of the most abundant natural polymers in the earth, it can regenerate. The modified starch is nontoxic, biodegradable. Recently, the removal and recovery of heavy metal ions from industrial wastewater has been a significant concern in all industrial branches owing to economic and environmental factors.This paper used starch as staple, then grafted by methyl acrylate, Which was carried out in aqueous media by the initiator of ceric ammonium nitrate and under a nitrogen gas atmosphere, to synthesize grafting starch(SMA). The chelating starch was synthesized by ethylene diamine which containing multiple amidocyanogen and acyl functions, and discussed the influences of the reactive temperature reactive time and catalyzers. The grafting percentage and grafting efficiency of the grafted starch (SMA) was measured, which was 54.14% and 28.42% respectively. The nitrogen content of the chelating starch was determined by the micro-Kjeldahl method, calculated the substituent. The structure of the chelating starch was determined by FTIR spectrum, then compared with starch and the grafting starch which educed starch was successfully grafted and chelated.This chelating starch was used to chelate copper( II) ions argentums( I) ions and lead( II) ions, and used Thermal Gravity Analysis to determine the weightlessness of the chelating starch before and after chelating, then estimated the chelating capacity.And determined the concentration of the metal ion solution before and after chelating by atomic absorption spectrometry, and discussed the influences of the pH value of the metal ion solution chelating time and the added capcity of chelator, found out the optimal condition of chelating.The chelating capacity of copper( II) ion was determined, which reached 3.33mmol/g, that of argentums( I) ion and lead(II) ion was 1.67mmol/g and 0.47 mmol/g, respectively. This proved the chelator possessing perfectable chelating capability, the chelating capacity to different metal ions was different.A sort of mature macromolecule materials was investigated, which has no second pollution to environment and can wipe off heavy metals from waste water. It has much significance from the viewpoint of environmental protection.