In this study, the organic mercapto polymer chelating agent (DDTC), Na2S and NaOH were selected as the capturing agent and used to remove complex Ni deeply from the electroplating plant wastewater. It paid the key focus on the study of reaction pH, pharmaceutical dosage, reaction time and other factors that could influence the removal of Ni. Besides, the mechanisms of Ni2+ removing by Na2S-DDTC was also discussed. The results showed that Na2S-DDTC had a high efficiency under the following conditions: ρ(Ni)=300mg/L of initial nickel concentration, pH 9.0, Na2S and DDTC dosing ratio was ρ(Na2S)/ρ(DDTC)=10, where ρ(Na2S)=600mg/L, ρ(DDTC)=60mg/L, the reaction time t=6.0min, the dosage of PAM was 1.0mg/L, leading to 0.064mg/L of residual Ni2+ concentration, which meeting the nickel special emission limit of the emission standard of pollutants for electroplating (<0.1mg/L). Furthermore, precipitation dissolution test about Na2S-DDTC mixed with Ni showed that, the hybrid sediment had a high sability under the state of nature, and did not cause secondary pollution. The particle size distribution was studied and a SEM method was used to observe the precipitation surface, the results indicated Na2S-DDTC had a certain synergy of flocculation and coprecipitation. Through this study, it could provide theoretical support for process design to deal with wastewater containing high complex Ni concentration using Na2S-DDTC.
戴文灿, 周发庭, 黄晴. Na2S-DDTC深度处理络合Ni高浓度电镀废水[J]. 中国环境科学, 2016, 36(3): 768-777.
DAI Wen-can, ZHOU Fa-ting, HUANG Qing. Application of high-level complex Ni removal from electroplating wastewater by the Na2S-DDTC. CHINA ENVIRONMENTAL SCIENCECE, 2016, 36(3): 768-777.
Fu F L, Chen R M. Removal of Cu2+ and dye from wastewater using precipitant N, N-bis-(dithiocarboxy) piperazine[J]. Environ. Chem., 2006,4:41-44.
[7]
Fu F L, Chen R M. Application of a novel strategy coordination polymerization precipitation to the treatment of Cu2+ containing wastewaters[J]. Sep. Purif. Technol., 2006,52:388-393.
[8]
Jiang J G, Wang J, Xu X, et al. Heavy metal stabilization in municipal solid waste incineration fly ash using heavy metal chelating agents[J]. Journal of Hazardous Materials, 2004,113: 141-146.
Thomas D N, Judd S J, Fawcett N. Flocculation modeling: a review[J]. Water Research, 1999,33:1579-1592.
[28]
Li Y, Zeng X, Liu Y, et al. Study on the treatment of copper-electroplating wastewater by chemical trapping and flocculation[J]. Separation and Purification Technology, 2003, 31(1):91-95.
Singh N, Bhattacharya S. Synthesis and characterization of some triorgano, diorgano, monoorganotin and a triorganolead heteroaromatic dithiocarbamate complexes[J]. Organomet. Chem., 2012,700:69-77.
[31]
Mostafa F, Amr E S, Raymond K S. The Infrared Spectrum and Structure of the[Ni(CN)4] -4 Ion[J]. Am. Chem. Soc., 1958, 80(9):2047-2048.
[32]
徐志固.现代配位化学[M]. 北京:化学工业出版社, 1987:173-175.
[33]
Singhal S, Garg A N, Chandra K. Thermal decomposition of transition metal dithiocarbamates[J]. Journal of Thermal Analysis and Calorimetry, 2004,78(3):941-952.
[34]
Zheng H L, Sun X P, He Q, et al. Synthesis and trapping properties of dithiocarbamate macromolecule heavy-metal flocculants[J]. Journal of Applied Polymer Science, 2008,110(4): 2464-2466.