摘要：

将粉煤灰与助熔剂混合进行高温焙烧制得热改性粉煤灰(TFA),对其进行表征并考察其对水中Cr(VI)的吸附性能.与原粉煤灰相比,TFA疏松多孔,比表面积显著提高.20℃下的吸附实验结果表明院当初始废水pH为6.7、Cr(VI)质量浓度为10.00mg/L、TFA加入量为4.0g/L、吸附时间为90min时,Cr(VI)去除率可达98.98%,吸附量为2.39mg/g.用拟二级动力学模型可较准确地描述TFA对Cr(VI)的吸附过程;吸附实验数据与采用Freundlich等温吸附模型得出的计算值吻合很好;降低温度有利于吸附反应的发生.

关键词: 热改性粉煤灰, Cr(VI), 吸附

Abstract:

Thermal modified fly ash(TFA)has been prepared through high temperature roasting of the mixture of fly ash and fluxing agent. It is characterized and its adsorption capacity for Cr(VI)from water is investigated. Compared with the raw fly ash,TFA is looser and more porous and its specific surface area is remarkably increased. The adso-rption experimental results under 20 ℃show that Cr(VI)removing rate can reach 98.98%,and adsorption capacity 2.39 mg/g,when the initial wastewater pH is 6.7,Cr(VI)mass concentration 10.00 mg/L,TFA dosage 4.0 g/L,and adsorption time 90 min. The pseudo-second order kinetic model can be used for the exact description of the adso-rption process of Cr(VI)by TFA. The experimental data of adsorption fit to the calculated value obtained fromFreun-dlich isothermmodel quite well. Lowering the temperature is in favor of the adsorption process.

Key words: thermal modified fly ash, Cr(VI), adsorption

中图分类号: 

• X703