湖水中的颗粒物对水体生物膜吸附铅、镉的影响

采用逐级过滤的方式对湖水进行过滤,并用含有不同粒径颗粒物的湖水进行生物膜的培养,以研究水中颗粒物对生物膜吸附痕量重金属的影响.研究结果表明,生物膜上铁、锰氧化物含量与水中总铁、总锰含量呈明显的线性关系,锰氧化物的含量受水中颗粒物粒径分布的影响很大.生物膜吸附铅、镉的热力学过程符合Langmuir方程,且膜上铁、锰氧化物吸附铅、镉的能力随着湖水中颗粒物粒径的减小呈增强的趋势.

Effects of Suspended Particulates in Nanhu Lake on Pb and Cd Adsorption to Surface Coatings Developed in the Natural Water

Surface coatings developed in different water obtained by means of stepwise filtration were used to assay the effect of suspended particulates on trace metal adsorption to them. There was a statistically significant correlation relationship between the contents of iron and manganese oxides on surface coatings and those in water, in which surface coatings were developed, even though manganese oxides was influenced obviously by particulates suspended in waters. The classical Langmuir adsorption isotherm was suitable to describe Pb and Cd adsorption to the surface coatings. It was observed that all of the iron oxides on the surface coatings contributed to Pb adsorption while manganese oxides on surface coatings developed in waters containing suspended particulates with a greater diameter contributed most to Cd adsorption. However, the adsorption capacities of Pb and Cd to the surface coatings increased with the decrease of diameter of suspended particulates in water.