硅灰石复合吸附剂对磷酸根吸附性的研究

Preparation of the wollastonite compound adsorbent and its adsorption behavior of phosphates

采用硅灰石与氯化镁等无机物在适宜条件下反应生成无机复合物吸附剂.讨论了溶液的pH值和吸附温度对吸附量的影响.通过对吸附剂的红外谱图和吸附前后颗粒表面积的变化、颗粒表面X-ray的衍射图分析,以阐述水中磷酸根被吸附的可能机理.结果表明:该吸附剂的最大吸附量为26.5 mg.g-1,该吸附剂去除水中磷酸根的主要机理为:在低pH时,水中的磷酸根与吸附剂表面上的羟基发生离子交换,在高pH时,水中的磷酸根与颗粒表面的金属氧化物反应形成金属磷酸盐而沉积在颗粒的表面.

The particulate inorganic adsorbent was obtained by reaction of wollastonite and aluminium chloride, magnesium chloride etc. , by microwaves. It was used to remove phosphate form aqueous solutions. The influence of suspension pH amt adsorptive temperature on phosphate removal was investigated. In addition, the yield and mechanisms of phosphate removal were explained on basis the ]R of adsorbent and values of specific surface area of the particles before and ＇after adsorption, X - ray spectroscopy. In this study, adsorption capacity is 26.5 mg · g ^- 1 and it is an efficient adsorbent for the removal of phosphates. When the pH is low, phosphate removal probably occurs with ion exchange ; at pH range of 7 - 11, the removal of phosphate predominantly takes place by precipitation mechanism between the surface and the phosphate forming metallic salts of phosphates.