粉煤灰对重金属Cu^(2+)和Zn^(2+)吸附作用研究

Adsorption of Zn^(2+) and Cu^(2+) by Coal Fly Ash in Coal Mine of Huainan City

选取淮南市洛河发电厂灰场的粉煤灰和粗沙、细粉沙、菜地土颗粒物,在不同的pH和颗粒大小条件下,通过室内实验,探讨了粉煤灰对Cu2+和Zn2+的吸附特性。结果表明,比较4种颗粒物对重金属Cu2+和Zn2+吸附作用(pH为7),吸附能力大小依次为粉煤灰>菜地土>细粉沙>粗沙;粉煤灰对Cu2+吸附能力要比Zn2+大。在同等粒径大小条件下(pH为7)的不同组成的颗粒物吸附能力大小依次为粉煤灰>菜地土>细粉沙。在5种不同pH条件下,粉煤灰在pH为12时吸附最少,在pH为6时吸附最多。不同颗粒物对重金属Cu2+和Zn2+吸附作用与颗粒物组成、粒径大小和pH条件有关。

Coal mine of Huainan has more than one hundred years of exploitation, which has resulted in serious influences on the ecological environment of the city. Sorption characteristics of Zn^2＋ and Cu^2＋ was analyzed at different pH values by selecting coal fly ash, coarse sand, fine sand and soil sampled from vegetable fields in coal ash area of Luohe power plant. Results showed that among the four powder materials, the coal fly ash had the largest capacity of adsorbing Cu^2＋ and Zn^2＋, while the coarse sand had the least one at pH 7, and the sorption capacity of these powders listed as coal fly ash 〉 soil in vegetable field 〉 fine sand〉 coarse sand at pH 7. The coal fly ash had higher adsorption capacity for Cu^2＋ than for Zn^2＋. So the capacity of sorption for heavy metal elements was related with both the diameter of particles and their components. At different pH values, the sorption capacity of coal fly ash was the highest at pH 6, and was the lowest at pH 12.