以海藻酸钠（SA）、聚乙烯醇（PVA）为原料，以丙烯酸（AA）为单体合成SA/PVA-g-AA复合凝胶吸附剂，对凝胶材料的官能团结构和微观形貌进行表征。以Co²⁺、亚甲基蓝（MB）为吸附对象，考察了pH值、Co²⁺/MB初始质量浓度、凝胶投加量等对凝胶吸附性能的影响，并对吸附动力学进行探究。结果表明：复合凝胶的比表面积和平均孔径分别为120.896 7 m²/g和8.069 08 nm，呈现多孔结构，有利于对Co²⁺、MB的吸附。凝胶在60 min内对Co²⁺和MB的吸附都达到平衡，且均与准二级吸附动力学模型拟合较好。pH值分别为3和7、凝胶投加量为0.15 g、初始质量浓度均为100 mg/L条件下，凝胶对Co²⁺、MB的最大去除率分别为95.01%和98.78%。

Using sodium alginate (SA), polyvinyl alcohol (PVA) as raw materials, acrylic acid (AA) as monomer to synthesize SA/PVA-g-AA hydrogel, the functional group structure and micromorphology of the hydrogel material were characterized. Using Co²⁺/MB as the adsorption object, the effects of pH, initial mass concentration, hydrogel addition on the adsorption of hydrogel performance were investigated, and the adsorption dynamics were explored. The results show that SA/PVA-g-AA hydrogel is a porous surface area of 120.896 7 m²/g and an average adsorption pore diameter of 8.069 08 nm which is beneficial to the adsorption of Co²⁺and MB. The composite hydrogel has a fast adsorption rate for Co²⁺/MB, and can reach adsorption equilibrium within 60 min, which is consistent with the quasi-second-order kinetic model. The maximum removal rates of Co²⁺ and MB reaches 95.01%and 98.78%, respectively, when the pH value is 3 and 7, the hydrogel dosage is 0.15 g, and the initial mass concentration is 100 mg/L.