【摘要】 [目的]对沸石进行负载氧化镧的改性,用于高氟水除氟,评价其吸附性能。[方法]用碱性氯化镧溶液浸渍—干燥—高温焙烧法对人造沸石进行改性,用模拟高氟水样进行静态吸附实验。[结果]动力学研究结果表明:吸附速度快,40min内接近吸附平衡,吸附速率可用拟二级动力学方程描述。吸附等温线表明:在平衡浓度很低(﹤1.0mg/L)时就接近饱和吸附量,平衡吸附数据符合Langmuir吸附等温线,饱和吸附量为7.49mg/g,吸附平衡常数为7.38L/mg。对浓度为10mg/L的含氟水样投加3g/L吸附剂,除氟率达91.4%。溶液pH值对吸附有影响,最佳吸附在pH4～5。水中共存CaCl2及温度对吸附的影响不大。[结论]氧化镧改性沸石对氟的吸附力强,除氟效率高。更多还原

【Abstract】 [Objective] To evaluate the adsorbent of a lanthanum oxide modified permutite to remove fluoride in water.[Methods]The modified permutite -base adsorbent was prepared by alkaline lanthanum chloride modification with impregnating -drying -roasting method,which was used to remove fluoride through static adsorption test.[Results]Kinetic study revealed that adsorption of fluoride was fast in the initial 40 min and followed pseudo-second-order kinetics.Adsorption isotherm showed that maximum adsorption capacity was approached at very low equilibrium concentration(﹤1.0 mg/L).The equilibrium adsorption data fitted well to Langmuir adsorption isotherm and showing maximum fluoride adsorption capacity of 7.49 mg/g and equilibrium constant of 7.38 L/mg.The removal ratio of fluoride against the water containing F-of 10 mg/L was 91.4% at the dosage of adsorbent was 3 g/L.The pH affected adsorption and the best efficiency was observed at pH 4-5.Co-existing CaCl2 of water and temperature marginally affected fluoride adsorption.[Conclusion]The lanthanum oxide modified permutite adsorbent shows high adsorption capacity and efficiency in fluoride removal.更多还原