羟基磷灰石微球的制备及废水除氟性能评价

以壳聚糖为模板,通过反向乳液聚合制备得到羟基磷灰石微球（CTS-HAP）,在利用X射线衍射（XRD）、扫描电镜（SEM）、能谱（EDS）、红外光谱（FT-IR）对改性和吸附前后微球进行微观分析基础上,测定其在氟化钠溶液中的平衡吸附量为17.8 mg/g（吸附pH=4）,微球对氟离子吸附符合多层分子吸附模型——Freundlich模型。针对氟离子质量浓度为2 789.2 mg/L、pH为1.7的酸性高含氟废水,设计二阶段除氟。初步除氟阶段氢氧化钙用量为10 864 mg/L,剩余氟离子质量浓度为200.6 mg/L,去除率为92.81%;深度除氟采用CTS-HAP微球吸附法,CTS-HAP微球用量为24 g/L,去除率为95.2%,满足处理后废水氟离子浓度要求。

Preparation of CTS-HAP and evaluation of fluoride removal performance in wastewater

CTS-HAP microspheres were prepared by reverse emulsion polymerization using chitosan as template.Based on the microscopic analysis of the microspheres before and after modification and adsorption by X-ray diffraction（XRD）,scan-ning electron microscopy（SEM）,energy dispersive spectroscopy（EDS） and infrared spectroscopy（FT-IR）,the equilibrium adsorption capacity of the microspheres in sodium fluoride solution was determined to be 17.8 mg/g（adsorption pH=4）.The adsorption of fluorine ion on microspheres conformed to the multi-layer molecular adsorption model—Freundlich model.For acidic high fluorine containing wastewater with fluorine ion mass concentration of 2 789.2 mg/L and pH of 1.7,two-stage fluo-ride removal was designed.In the preliminary fluoride removal stage,the dosage of calcium hydroxide was 10 864 mg/L,the mass concentration of residual fluoride ion was 200.6 mg/L,and the removal rate was 92.81%.CTS-HAP microsphere adsorption method was used for deep fluoride removal,with the dosage of 24 g/L and the removal rate of 95.2%,which met the requirements of fluoride ion concentration of treated wastewater.