【摘要】 以四水硝酸钙和九水硝酸铝为原料、尿素为沉淀剂，利用微波加热、水热合成法制备了前驱体Ca-Al-LDHs,焙烧后得到钙铝类水滑石(Ca-Al-LDOs),并将其用于吸附废水中氟离子。结果表明，Ca-Al-LDOs具有明显的类水滑石层状结构；吸附材料在pH=2、F~-初始浓度500 mg/g、吸附时间180 min、吸附剂添加量2.5 g/L条件下，吸附容量达到173.9 mg/g,氟去除率达到92.01%;其吸附行为符合Freundlich等温吸附模型和准二级动力学方程；吸附剂经脱附溶液处理后可再生重复利用，8次循环再生后，除氟率依旧能达到68.92%。更多还原

【Abstract】 With Ca（NO₃）₂·4H₂O and Al（NO₃）₃·9H₂O as raw materials and urea as precipitant, a precursor Ca-Al-LDHs was prepared by microwave heating and hydrothermal synthesis. A product of Ca-Al hydrotalcite（Ca-Al-LDOs） was obtained after roasting, and it was used to adsorb fluorine in wastewater. It is found that Ca-Al-LDOs are of typical layered structure similar to hydrotalcite. With pH of 2, initial concentration of F^- ion at 500 mg/g, adsorbent dosage of 2.5 g/L and reaction time of 180 min, the adsorption capacity reaches 173.9 mg/g and the removal rate of fluorine reaches 92.01%. It is found that the process of adsorption conforms to the Freundlich adsorption isotherm mode, and its kinetics conforms to the quasi-second-order kinetic model. The adsorbent Ca-Al-LDOs can be reused after desorption, with defluorination rate keeping at 68.92% after 8 cycles of regeneration.更多还原