钢渣吸附去除水溶液中磷的研究  

Adsorption of Phosphorus from Aqueous Solution on Steel Converter Slags

作　　者：赵桂瑜[1] 周琪[1] 谢丽[1] 

机构地区：[1]同济大学污染控制与资源化国家重点实验室,上海200092

出　　处：《同济大学学报（自然科学版）》2007年第11期1510-1514,共5页Journal of Tongji University:Natural Science

基　　金：上海市科委国际合作项目(062307038)

摘　　要：研究了钢渣对水溶液中磷素的等温吸附特征和吸附动力学过程,考察了初始溶液浓度、钢渣粒度和温度对吸附作用的影响,计算了钢渣对磷素的吸附速率.结果表明:钢渣的吸附除磷作用主要是通过化学沉淀和配位体交换两种途径实现的,符合Langmuir等温吸附模型,理论饱和吸附量为4.27×104mg.kg-1.钢渣对磷素的吸附量受粒度和温度影响不大,但随初始溶液浓度的增大而增大.钢渣粒度越小,吸附速率越高,对吸附作用越有利.温度较高,初始浓度较低的条件下,吸附速率较大.钢渣吸附除磷的吸附动力学过程符合准二级动力学模型,由该模型可以估算出钢渣对水溶液中磷素的平衡吸附量,误差基本在14%之内.This paper focuses on a study of phosphorus adsorption onto steel converter slags. Phosphorus adsorption isotherm and its kinetics were examined and effects of temperature, adsorbent particle size and initial phosphorus concentration were investigated to reveal reaction mechanisms. Phosphorus adsorption rates of steel converter slags under different conditions were calculated for comparison. Results show that precipitation reactions and ligand exchange with elements of calcium and iron in steel converter slags are the dominating mechanisms for phosphorus removal. Langmuir isotherm is found to fit the data of phosphorus adsorption onto steel converter slags well, with saturation adsorption capacity of 4.27 × 10^4 mg· kg^- 1. The capacity of phosphorus adsorption improves with the increase of initial phosphorus concentration but is not affected by temperature and adsorbent particle size. Phosphorus ad- sorption rate is observed to decrease with larger particle size, but increase under low initial phosphorus concentrations and higher temperature. The change of phosphorus concentration with time can be described by the pseudo second-order kinetics with correlation coefficient of 0.98. Accordingly,amnounts of phosphorus adsorbed at equilibrium can be calculated with error below 14 %.

关 键 词：钢渣 吸附 动力学 

分 类 号：X52[环境科学与工程—环境工程]