Using sodium lignosulfonate and copper chloride dihydrate as raw materials, and activated carbon modified materials under different synthetic conditions were prepared by calcination under N₂ atmosphere by impregnation and activation. The structure and surface morphology of the prepared materials were studied by X-ray diffraction (XRD), infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS) and other testing methods. Taking K₂Cr₂O₇ solution with mass concentration of 20 mg/L as the research object, the Cr(Ⅵ) content in the solution was detected by Diphenyl carbamide chromogenic method, and the adsorption capacity of the prepared activated carbon modified materials was calculated. According to the experimental results, when the proportion of copper is 20% and the calcination temperature is 700 ℃, the adsorption performance of the material is the best, and the adsorption capacity is 72.2 mg/g. The adsorption process conforms to the Langmuir monolayer adsorption and Pseudo-second-order kinetics.