Home – Home – Jornals – Chemistry for Sustainable Development 2018 number 4

The sorption activity of carbamide-containing sorbent made of aspen bark was studied with respect to nickel, zinc and lead from aqueous solutions with different metal concentrations. The effect of carbamide content in the aspen bark sorbent on its sorption activity with respect to admixtures under investigation was revealed. It was demonstrated that the adsorption-based deposition of 10.7 mass % of carbamide on the support made of aspen bark causes an increase in the capacity of the sorbent by a factor of 1.9-3.3 depending on metal nature. It was established that the resulting aspen bark sorbent is characterized by the high sorption capacity: the limiting sorption of lead, zinc and nickel is 91.17, 25.78 and 23.34 mg/g, respectively. The data on the kinetics of metal sorption and their analysis with the help of the models of pseudo-first and pseudo-second order are reported. The acidity of aqueous solutions providing efficient sorption of the metals under study was determined: pH 5.5-6.0 for zinc solutions and pH 5.5-7.0 for lead and nickel solutions. It was shown that the carbamide-containing aspen bark sorbent is efficient for the purification of low-concentration metal solutions: purification degree of the solutions containing 10.5 and 1.0 мg/l admixtures is not less than 66.7 and 89.9 %, respectively. The stability of the developed carbamide-containing sorbent to carbamide washing out was revealed in the studies of nickel, zinc and lead sorption. In combination with the high sorption activity, this determines the promising character of the use of this sorbent for additional purification of technical-grade water from metal admixtures.