Preparation Of Starch Xanthate And Its Heavy Metal Wastewater Treatment Applications

The thesis deliberated synthetization of starch xanthate. The research results obtained showed that, sulphonating extent of synthetic starch xanthate was high, under room temperature, time 120 minutes, mol ratio of starch, sodium hydroxide and disulphide being 10 : 4 : 3, It was to say that sulphur content and supplent extent were high. It deliberated that magnesium sulphate and epichlorohydrin affecting on synthetization of starch xanthate, mass ratio of synthetic starch xanthate and Magnesium sulphate was 8: 1, Mass ratio of synthetic starch xanthate and epichlorohydrin was 10 : 1, Magnesium sulphate and epichlorohydrin didn't affect sulphonating extent of synthetic starch xanthate, but did enhance cross extent and nature of insoluble. Sulphur content of the product was 8.41%, and supplent extent was 0.245.Research of treatment of starch xanthate in heavy metal ions wastewater showed that, under the same repercussion condition, the function of insoluble cross starch xanthate was superior in soluble starch xanthate, insoluble starch xanthate, soluble cross starch xanthate and insoluble cross starch xanthate handled heavy metal ions Cu2+, Zn2+, Ni2+, and Cr3+ wastewater, It was to say that consistency of residue of heavy metal ions was below 0.95mg/L, and extrication proportion was above 97%. However, under quality ratio of insoluble cross starch xanthate and heavy metal ions being 4.3 : 1, 3.9 : 1, 4.3 : 1 and 5.9 : 1, value of pH neutral or weak alkal, time 30 minutes, extrication proportion of heavy metal ions wastewater was above 99%. The higher concentration of heavy metal ions Cu2+, Zn2"1", Ni2+, and Cr3+ was, the largerdelivered capacity of starch xanthate was. The higher sulphur content of starch xanthate was, the larger delivered capacity of starch xanthate was. Remainderes of heavy metal ions Cu2+, Zn2+, Ni2+, and Cr3+ were stable, they didn't produce the secondary pollution. Under proper remedy capacity, value of pH and reaction time, treatment effect of the heavy metal ions Cu2+, Zn2+, Ni2+ wastewater was good, consistency of residue of heavy metal ions was below 0.50mg/L, and extrication proportion was above 98.5%. Under suitable remedy quantity, value of pH and reaction time, treatment effect of Cr3+ wastewater of Xiang Xiang tannery was good, consistency of residue of heavy metal ions was below 0.05mg/L, and extrication proportion was above 99.5%.Reseach of solution chemistry agent, differential thermal analysis and infrared optical spectrum analysis showed mechanism of starch xanthate in watewater treatment. Oxidation-reduction reaction, supplent repercussion and commutation and adsorption reaction all existed in Cu2+ wastewater, but just supplent repercussion andcommutation and adsorption reaction existed in heavy metal ions Zn2+, Ni2+, and Cr3^ wastewater.