本文通过对天然硅藻土进行酸洗和超声波复合改性处理来改善其吸附性能，并以此作为吸附剂处理皮革废水中的重金属污染物。利用红外光谱分析（FTIR）、扫描电镜分析（SEM）、比表面积分析（BET）以及X射线衍射分析（XRD）的方法，对比了硅藻土改性前后组织形态以及微观结构的变化；通过振荡吸附实验，研究了天然硅藻土和改性硅藻土对重金属离子Cd2+、Pb2+的吸附性能。结果表明：改性处理后，硅藻土表面孔隙的杂质明显减少，晶体结构更加有序整洁，孔径与比表面积均有所增长，分别为：13.781 nm和76.081 m2·g-1；当改性硅藻土投加量为8 g/L，吸附时间为60 min时，吸附反应达到平衡，且达到对重金属离子的最大去除率，对Cd2+的最大去除率为52.95%，比天然硅藻土高出19.24%，对Pb2+的最大去除率为89.37%，比天然硅藻土高出34.37%；改性处理之后，最大吸附容量从Cd2+11.8625 mg/g、Pb2+12.5486 mg/g升高到了Cd2+14.1451 mg/g、Pb2+14.5479 mg/g；改性前后硅藻土对两种重金属离子的吸附过程较好地符合Freundlich吸附等温模型和二级动力学模型。%The nature diatomite was treated by acid pickling and ultra sonication as composite modification to improve its adsorption property,as an adsorbent for the treatment of heavy metal pollutants in leather wastewater. The means of BET,XRD,FTIR,SEM were used to compare the microstructure and tissue of nature and composite modified diatomite;through adsorption test, the adsorption properties of Cd2+and Pb2+of the heavy metal ions by the natural diatomite and modified diatomite were studied. The results showed that:after modification, the surface pores of diatomite were decreased obviously, and the crystal structure was more orderly and clean;the pore size and specific surface area were increased, which reached 13.781 nm and 76.081 m2·g-1, respectively. The adsorption equilibrium was attained within 60 min. The result of adsorption test showed that modified diatomite was effective removal of heavy metal Cd2+and Pb2+with 8 g/L within 60 min, with the adsorption rates attaining Cd2+ 52.95%and Pb2+ 89.37%, 19.24%and 34.37% higher than the natural diatomite, respectively. The adsorption capacities of nature diatomite for the heavy metal were Cd2+11.8625, Pb2+12.5486 mg/g. After modified treatment, the adsorption capacities were Cd2+ 14.1451, Pb2+ 14.5479 mg/g, with the obvious effect. The adsorption process of the heavy metals by different diatomite was better in accord with Freundlich adsorption isothermal model and the two stage dynamic model.
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