污泥基陶土对水中Pb^(2+)、Cd^(2+)、Ni^(2+)、Cr^(3+)离子的吸附性能研究

Adsorption of Pb^(2+), Cd^(2+), Ni^(2+) and Cr^(3+) by municipal sludge based pottery clay in aqueous solution

利用污水厂污泥、河道淤泥、粉煤灰和加拿大一枝黄花等废弃物为主要原料,制备出一种污泥基陶土(SBPC),研究了其对Pb^(2+)、Cd^(2+)、Ni^(2+)、Cr^(3+)4种重金属混合溶液的吸附效果,并以Cr^(3+)为例研究其吸附机理.结果表明,在低浓度重金属混合溶液中,SBPC对Cr、Pb的去除率可达90%以上,而对Cd、Ni的去除率低于15%;在单一重金属铬溶液中,SBPC对Cr^(3+)的最大吸附量为4.32 mg·g-1,其吸附等温线符合Freundlich模型;吸附机理主要包括表面沉降、阳离子置换、取代反应、Cr^(3+)水解以及静电吸附.

By employing municipal sludge, river silt, coal soots and Solidago canadensis L. as raw materials, a new kind of sludge based pottery clay（SBPC） is prepared, and the adsorption properties of SBPC on Pb^2＋,Cd^2＋,Ni^2＋ and Cr^3＋ in aqueous solution are investigated. The results show that the removal efficiency on Pb and Cd can be achieved by more than 90%, while that on Cd and Ni is under 15% in the mixed heavy metals solution. The maximum adsorption capacity on Cr^3＋ is 4.32 mg·g^-1 in the single solution of Cr^3＋, and the adsorption isotherm on Cr^3＋ is consistent with the Freundlich model. The sorption mechanism mainly involves surface precipitation, cation exchange and substitution reaction, Cr^3＋ hydrolysis and electrostatic adsorption.