Selective Adsorption of Silver Ions from Highly Acidic Aqueous Solutions by Polymers Containing Multiple Sulfur Groups

Abstract

A polymer (PDMTD) containing multiple sulfur groups is prepared and used for selective adsorption of silver ion from aqueous solution. The batch adsorption experiments are conducted to research the effects of the different parameters on adsorption of silver ion, including pH, adsorption time, and initial Ag(I) concentration. The maximum uptake of Ag(I) is 127.89 mg/g at pH = 1. The adsorption equilibrium data are fitted with different isotherm and kinetics models. The results show that the adsorption process of Ag(I) follows a pseudo-second-order kinetic model and Langmuir isotherm mode. Chelation interaction between Ag(I) and sulfur and nitrogen atom is the main adsorption mechanism. PDMTD shows the good selectivity from the coexisting ions and can be reused at least five times. The polymers containing multiple sulfur groups have wide application prospect to selectively capture silver ions from highly acidic aqueous solutions.