The structure of epichlorohydrin-dimethylamine polymer flocculants with different modifying agents and their properties for decoloration of wastewater

Flocculants epichlorohydrin-dimethylamine polymers (EPI-DMA) were synthesized by polycondensation of dimethylamine and epichlorohydrin with modifying agents including 1,2-Diaminoethane,diethylenetriamine and triethylenetetramine. The influences of the amount of modifying agents on the characteristics of EPI-DMA were investigated. IR and TEM were used to test the structure of EPI-DMA. EPI-DMA flocculants were also used for decoloring wastewater. The results showed that the addition of modifying agents changed the viscosity and the cationic degree of EPI-DMA. The IR spectrums of EPI-DMA were analogical, but the morphologies of the flocculants were different. When treating activated red dye wastewater, EPI-DMA flocculants showed both charge neutralization and adsorption bridging functions,while for reductive red dye wastewater EPI-DMA performed mainly as charge neutralization; The experimental results for treating raw wastewater showed that the decolorization rate and COD_ Cr removal rate could reach 80% and 60% respectively.