Preparation Of WPCB Modified Chelate Materails And Study Of Their Adsorption Properties

In the rapid development of science and technology in modern society, waste electronic products increased year by year, printed circuit board(PCB) as an important component of electronic products has become the largest number of electronic garbage waste. The technology of the WPCB’s non-metal materials resource recycling and processing has aroused great attention. In addition, with the rapid development of global industrialization, industrial waste water emissions increase, the problem of water pollution caused by heavy metals is also becoming increasingly serious. At present, the adsorption method is widely applied in treating the heavy metal waste water because of its good treatment efficiency and no secondary pollution. But, most adsorption material exist the problems of difficulty to get raw material and the cost is higher, therefore, find a more cheap and stable performance of the materials to produce heavy metal chelating adsorption material is particularly important.Comprehensive the above two problems in the field of the environment, this paper provides a new train of thought. Three different functional groups chelating adsorption material were prepared by taking WPCB as raw material, through chemical modification by monochloroacetic acid, thiosemicarbazone and carbon disulfide. They were MCA-WPCB, TSC-WPCB and DTC-WPCB. Their functional groups were characterized to confirm by infrared spectroscopy. These three chelating material were used to adsorb Cu2+, Pb2+ and Ag+ from aqueous solution. The results showed that:MCA-WPCB have better adsorption effect on Cu2+, Pb2+ and Ag+. Solution pH had great effect on the adsorption effciencies and the optimum experimental pH was 5. The adsorption effciencies on MCA-WPCB of the three metal ions decreased with the increase of temperature, but it has little affect on adsorption of Ag+, this indicated that the adsorption processes were exothermic. It was found that all the adsorption of Cu2+, Pb2+ and Ag+ on MCA-WPCB was a fast adsorption process that could be reached equilibrium within 30 minutes. The adsorption processes could be well described by the pseudo-second-order equation. It showed that the major controlling step of adsorption rate was chemical adsorption. By analyzing the adsorption isotherms, the MCA-WPCB’s adsorption of Cu2+ and Pb2+ fitted Langmuir model, but Ag+ adsorption fitted Freundlich model.TSC-WPCB have better adsorption effect on Cu2+ and Ag+, but adsorption effect on Pb2+ was not obvious. Solution pH have littler effect on the adsorption effciencies on TSC-WPCB. The adsorption effciencies on TSC-WPCB of the three metal ions decreased with the increase of temperature, this indicated that the adsorption processes were exothermic. It was found that the adsorption of Ag+ on TSC-WPCB was a fast adsorption process but the adsorption of Cu2+ and Pb2+ was slowly. The all adsorption processes could be well described by the pseudo-second-order equation. By analyzing the adsorption isotherms, the TSC-WPCB’s adsorption of Cu2+ fitted Langmuir model, but Ag+ and Pb2+ adsorption fitted Freundlich model.DTC-WPCB have better adsorption effect on Pb2+ and Ag+, but adsorption effect on Cu2+ was not obvious. The suitable pH for DTC-WPCB was a wide range, DTC-WPCB have better adsorption performance when pH from 2 to 7. The adsorption effciencies on DTC-WPCB of the three metal ions decreased with the increase of temperature. In the process, ΔH is Plus and ΔG is negative, indicated that the adsorption processes of DTC-WPCB was spontaneous and endothermic. It was found that the adsorption of Ag+ and Pb2+ on DTC-WPCB was a fast adsorption process but the adsorption of Cu2+ was slowly. The all adsorption processes could be well described by the pseudo-second-order equation. By analyzing the adsorption isotherms, the DTC-WPCB’s adsorption of Cu2+, Ag+ and Pb2+ all fitted Freundlich model.