碳酸羟基磷灰石对水中氟离子的吸附研究

Fluoride Adsorption from Aqueous Solution by Carbonate Hydroxyapatite

利用XRD和TEM对沉淀法合成的纳米碳羟基磷灰石(CHA)样品进行表征。考察原料配比、p H值、吸附时间和氟离子(F~–)初始浓度、投加量和吸附温度对CHA吸附水中F~–的影响。结果表明:碳酸根掺杂有利于磷灰石对氟的吸附,当[Ca^(2+)]/[PO_4^(3–)]和[CO_3^(2–)]/[PO_4^(3–)]原料摩尔配比分别为1.67和0.12时,除氟效率较佳。当以此原料配比的CHA作为除氟剂,按1 mg/m L的投加量浸渍于4 mg/L Na F溶液中吸附6 h,控制吸附温度为35-65℃,p H值为4.0-8.0,除氟效率均高达95%以上。

Nano-carbonate-hydroxyapatite （CHA） synthesized by wet chemical method was characterized by XRD and TEM. The influence of various parameters, including raw material ratio, pH value of the solution, adsorption time, initial concentration of F-, adsorbent dose and adsorption temperature on the fluorine adsorption were investigated. Experimental results showed that the carbonate doping was beneficial to the F-adsorption. The optimized molar ratio of [Ca2＋]/[PO43-] and [CO32-]/[PO43-] were 1.67 and 0.12. When this CHA powder was impregnated in 4 mg/L NaF solution with the adsorbent dose of l mg/mL for 6 h, the adsorption temperature at 35- 65℃, and the pH value in the range of 4.0 - 8.0, the removal efficiency was above 95%.