| 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...
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