Preparation of Cu(II) ions adsorbent from acrylic acid-grafted corn starch in aqueous solutions

Acrylic acid graft onto corn starch with excellent water holding capacity were successfully synthesized and employed for copper ions removal in aqueous solution. N,N-methylenebisacrylamide and potassium persulfate effectively worked as cross-linking agent and the reaction initiator for copolymerization reaction, respectively. The data of FTIR confirmed that acrylic acid has been grafted onto starch. The effect of time on the water holding performance was investigated, and its maximum value was 96.6g/g. The copolymers were dispersed in aqueous solution of Cu2+ ions and form polymer-copper ions complex. The copper ions removal capacity of grafted starch was investigated by UVvisible spectrophotometry as a function of pH, water holding capacity, the content of NaCl, and the initial concentration of copper ions. In the presence of NaCl, the highest copper ions removal capacity was 2.56mmol copper ions per gram of grafted starch, and 85.3% of copper ions have been removed. The isothermal study indicated that the adsorption data could be well modeled by Langmuir isotherms.