Synthesis and Adsorption Performance of Dithiocarbamate Resin Towards Waste Water Containing Fe³⁺, Co²⁺ and Mn²⁺

Dithiocarbamate (DTCR) resin was synthesized using primary amine resin D309 in methanol-water solution way and characterized by FTIR and SEM. Adsorption mechanism and ion removal ability of DTCR were investigated by isothermal adsorption experiments and kinetics experiments. The results obtained from the equilibrium isotherms adsorption studies on three metal ions of Fe³⁺, Mn²⁺ and Co²⁺ indicate that the adsorption conforms to the Langmuir isotherm equation. The maximal absorption capacity for Fe³⁺, Mn²⁺ and Co²⁺ reaches up to 25.07, 20.58 and 41.87 mg/g at 25 ℃, respectively. The kinetics experiments show that DTCR has a high adsorption rate and the adsorption reaches equilibrium in 4 h. In the dual metal ions system, the order of the adsorption selectivity for the three metal ions is Mn²⁺＞Co²⁺＞Fe³⁺. In the presence of Ca²⁺ and Mg²⁺, the removal rate of Co²⁺ stays at 97%, and the removal rate of Fe³⁺ rises from 50% to 98%, but the removal rate of Mn²⁺ declines from 92% to 80% under competitive conditions.