Abstract:

A series of Zn-Al hydrotalcite-like compounds (HTALs) were synthesized by the coprecipitation method, and the factors affecting their phosphate adsorption capacity were investigated.The results showed that the highest phosphate adsorption up to 72.46 mg P·g^-1 in sludge filtrate of a sewage work by Zn-Al HTALs was obtained when the adsorbent was prepared at 70℃ using NaOH solution as the coprecipitant, aged for 6 h and calcined at 300℃ for 4 h.The fitness of kinetic models for phosphate adsorption on Zn-Al-300 followed the order of pseudo second-order equation> Elovich equation >the pseudo first-order equation.In addition, the adsorption isotherm was shown as the Langmuir-type.

Key words:

Zn-Al类水滑石, 污泥脱水液, 吸附, 磷酸盐

摘要：

采用共沉淀法制备了一系列Zn-Al类水滑石吸附剂，并考察了制备条件对其磷酸盐吸附性能的影响。结果表明，在制备温度为70℃、共沉淀剂为NaOH、陈化时间为6 h及焙烧温度为300℃时得到的Zn-Al类水滑石对城市污水处理厂污泥脱水液中磷酸盐的吸附效果最好，其饱和吸附容量达72.46 mg P·(g吸附剂)^-1。该吸附剂吸附水中磷的动力学拟合效果表现为假二级动力学方程>Elovich方程>假一级动力学方程。吸附等温线符合Langmuir吸附模型。

关键词:

Zn-Al类水滑石, 污泥脱水液, 吸附, 磷酸盐