【作者】 季靓；

【导师】 李义久；

【作者基本信息】 同济大学 ， 分析化学， 2007， 硕士

【摘要】 电子工业的迅猛发展使得重金属废水的排放量逐年增加，水质也更趋复杂。采用传统的化学沉淀法进行处理，排放水中的重金属含量仍较高，甚至不能达标排放，从而导致进入环境水体中的重金属总量越来越大。因此，采取有效的处理手段，降低电子工业排放废水中重金属浓度，同时又不产生二次污染具有重要的环境和经济效益。 本论文在课题组前期工作的基础上，完成了二硫代氨基甲酸改性淀粉（DTCS）重金属捕集剂整个合成工艺的优化，包括交联、醚化、胺化、加成等所有步骤，确定了成熟、稳定的制备工艺。在合成工艺的胺化步骤中，通过对N取代基筛选及参数的优化，确定了合适的N取代基及该取代基的最佳制备参数。采用该工艺制备了多批次产品，结果表明其性能优异、稳定性，重现性好，为下一步的性能及机理研究提供了可靠的产品保证。 论文研究了DTCS在多种不同环境条件（pH值、实验温度、反应时间、络合离子等）的水体中对Cu²⁺、Pb²⁺、Zn²⁺、Cd²⁺、Ni²⁺这五种重金属离子的捕集性能。首次考察了DTCS对重金属离子的饱和捕集量、对实际废水的处理效果、捕集物在水体中的稳定性及出水中残留的TOC值，确定了影响其捕集性能的主要因素，明确了合适的应用条件。 结果表明：在浓度均为1mmol·L^-1的单一重金属溶液中，DTCS对铜、铅、锌、镉、镍的最大去除率均能达到99.9％以上，对五种重金属离子的最大饱和捕集量分别为1.77、1.12、0.80、0.92、0.83mmol·g^-1；在浓度均为0.1mmol·L^-1的含络合剂EDTA的重金属溶液中，DTCS对铜、铅、锌、镉、镍的最大去除率分别为98.04％、99.94％、96.74％、99.82％、98.82％；在浓度为124.66mg·L^-1的含铜电镀废水中，DTCS对Cu²⁺去除率基本稳定在99.9％以上，出水浓度达到了国家一级排放标准。 论文通过扫描电镜、XRD等对合成产品及捕集物进行分析，观察到DTCS通过DTC基团与重金属离子形成的螯合物，并且讨论了DTCS捕集重金属的原理。 与小分子量有机捕集剂以及中和沉淀法相比，DTCS具有更优良的重金属更多还原

【Abstract】 With the development of industry, plenty of heavy-metal wastewater containing chelating agents is draining out of the manufacture world. Traditional chemical precipitated method can not meet the emission regulation to treat the ever increasing wastewater. Finding new efficient measures to decrease the heavy metal concentration without second pollution has become the top priority in the environment protection field.In this dissertation, corn starch is modified and applied for the removal of heavy metals from aqueous solutions. Starting from corn starch, cross-link starch derivative containing dithiocarbamate group（DTCS） is synthesized via a series of processes including crosslink, etheration, amination and addition reaction with CS2. According to the analysis of these processes, the technology is optimized and a new kind of DTCS is produced, which has better performance, repetition and stability.Some parameters affecting metal removal are investigated in this dissertation including pH, temperature, time and complexing agent. The best saturation, TOC and the performance on the plating waster water are researched for the first time in this dissertation.Experimental results show that in simple solution whose concentration is lmmol·L^-1, the removal efficiencies are all 99.9% and the best saturations are Cu²⁺1.77, Pb²⁺1.12, Zn²⁺0.80, Cd²⁺0.92, Ni²⁺0.83 mmol·g^-1. In the solution with complexing agent EDTA whose concentration is 0.1mmol·L^-1, the removal efficiencies are Cu²⁺98.04%, Pb²⁺99.94%, Zn²⁺96.74%, Cd²⁺99.82%, Ni²⁺98.82%. In the plating waster water whose concentration of Cu²⁺ is 124.66mg·L^-1, the removal efficiency is 99.9%. SEM and XRD of the compounds indicate that the chelating bonds are formed between this chelating reagent and metals.The experimental results show that the new kind of DTCS has good removal capability to heavy metals and it is convenient, safe and jarless. We can say that DTC-grafted starch is a low-cost chelating reagent for heavy metals, with good更多还原