New Analytical Methods for Separation and Identification of Heavy Metals (). A Study on the Adsorption and Recovery of Cu() ion by Amberlite XAD-7 Rrsins Impregnated with Chelating Agents

摘要

The adsorption behavior of some chelating agents on the Amberlite XAD-7 resin was studied to obtain the optimum conditions for the preparation of chelating agent-XAD-7 resins. The chosen chelating agents are cupferron (CP), diphenylcarbazone (DPC), salicylaldoxime (SAO), thiosalicylic acid (TSA), and dimethylglyoxime (DMG), which have been well known chelating agents to Cu(￥±) and Ni (￥±) ions. Among the chelating agent-XAD-7 resins, SAO-XAD-7 and DMG-XAD-7 resins were evaluated as appropriate impregnated resins by investigating their stabilities in the wide pH range and high abilities to adsorb Cu(￥±) and Ni(￥±) ions. The selective adsorption of Cu(￥±) from Ni(￥±) was possible by changing pH condition by SAO-XAD-7 resin. The adsorption capacities of SAO-XAD-7 and DMG-XAD-7 for Cu(￥±) were 7 ?? 10-3mmol Cu(￥±) per gram of resin and 2 ?? 10-3mmol Cu(￥±) per gram of resin, respectively. The quantitative recovery of Cu(￥±) adsorbed by the resin was demonstrated. The adsorption behavior of Cu(￥±) and Ni(￥±) by the single and mixed bed of chelating agent-XAD-7 resin was discussed.