基于一种硫磷复配体系的土壤化学固定技术研究

发布时间：2018-03-06 21:29

本文选题：复合重金属　切入点：硫脲　出处：《应用化工》2017年02期 　论文类型：期刊论文

【摘要】：以硫脲和羟基磷酸钙复配体系为固定剂,结合SEM表征手段,研究其在水溶液中对重金属离子(Pb2+、Cd2+、Hg2+、Cu2+和Zn2+)的去除反应及其固定过程。结果表明,羟基磷酸钙对重金属离子具有良好的吸附性能,硫脲水解释放的硫离子与重金属离子反应生成稳定的硫化物。应用均匀设计实验方法探究了硫脲用量、羟基磷酸钙用量、氢氧化钠用量、土壤含水率及固定周期等因素对土壤中重金属固定效果的影响,并结合二次多项式逐步回归法确定了最优固定条件:硫脲、羟基磷酸钙和氢氧化钠的使用量与重金属总量摩尔比分别为5∶1,3.044 2∶1和1.340 1∶1,土壤含水率33.26%,固定时间0.25 d。在该条件下,土壤中重金属固定率:铅99.57%、镉91.41%、汞93.01%、铜93.26%、锌91.37%。统计学分析表明该最大值可靠,该条件可以作为固定剂使用的最佳条件。
[Abstract]:Using thiourea and calcium hydroxyl phosphate as immobilized agents and SEM characterization, the removal of heavy metal ions (Pb2 + CD2 + Hg2 + Cu2 and Zn2) in aqueous solution was studied. Calcium hydroxyl phosphate has good adsorption performance on heavy metal ions, and the sulfur ions released by hydrolysis of thiourea react with heavy metal ions to form stable sulfides. The amount of thiourea and calcium hydroxyl phosphate are studied by uniform design method. The effects of sodium hydroxide dosage, soil moisture content and fixation period on the fixation effect of heavy metals in soil were studied. The optimal fixation conditions were determined by quadratic polynomial stepwise regression. The molar ratios of hydroxyl calcium phosphate and sodium hydroxide to the total heavy metals were 5: 1, 3.044 2: 1 and 1.340 1: 1, respectively. The soil moisture content was 33.26 and the fixed time was 0.25 d. The fixed rates of heavy metals in soil are: lead 99.57, cadmium 91.41, mercury 93.01, copper 93.26, zinc 91.37. Statistical analysis shows that the maximum value is reliable, and this condition can be used as the best condition for fixation.
【作者单位】：上海应用技术大学化学与环境工程学院;上海化工研究院;
【基金】：2014上海市科委土壤专项(14231200502)
【分类号】：X53;S153;TQ421

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