Abstract: Aiming at the problem of Cd²⁺ pollution in water, the experiment of Cd^2+ adsorption by ecologically safe scoria in low temperature water was carried out, and we analyzed the effect and influence factors of Cd²⁺ adsorption by scoria. The results show that scoria is a kind of Cd²⁺ adsorbent with potential value. The removal rate reaches 97.10% in 0.5 mg/L Cd²⁺ solution using 1.00 g scoria at 10 ℃. The neutral environment is conducive to adsorbing Cd²⁺. 
Ca²⁺,Mg²⁺ and NO^-₃ in groundwater can inhibit the adsorption of Cd²⁺by scoria, while Fe²⁺ and Mn²⁺ have little inhibitory effect. When the mass concentrations of NH⁺₄ and NO^-₂ are less than 50 mg/L, they have no effects on the adsorption of Cd²⁺ by scoria. When the mass concentrations are more than 50 mg/L, they have inhibitory effects on the absorption. SO^2-₄ has no effect on the adsorption. HCO^-₃ with higher mass concentration has promotion effect on the adsorption of Cd²⁺ by scoria.

Key words: scoria, groundwater, adsorption, Cd ion, influence factor