改性活性炭对水溶液中氟离子的吸附性能

摘要

The new adsorbent magnesia modified activated carbon ( MgO-AC) was used to remove fluoride from aqueous solution. The effects of contact time, optimization of adsorbent dosage, pH and temperature on fluoride adsorption efficiency were studied in a batch system. Adsorption reaches equilibrium in 180 min. The optimum dose was fixed as 2. 8 g/L. Solution pH is one of the most important parameters affecting adsorption, and the optimum pH rang of the fluoride adsorption on MgO-AC was 6. 0-8. 0. Fluoride adsorption isotherm was well fitted by the Langmuir model, and the adsorption capacity increases with rising temperature. Kinetic studies showed that the kinetic data were well described by the pseudo-second-order kinetic model. The adsorption mechanism is discussed preliminary. Low cost, and high adsorption capacity indicate that the MgO-AC could be effectively employed as a promising fluoride adsorbent.%选用氧化镁改性活性炭(MgO - AC)为新型吸附剂,用于去除水溶液中的氟离子.系统地研究了反应时间、吸附剂最佳投加量、pH、温度等因素对吸附剂除氟性能的影响情况.反应系统达到吸附平衡的时间为180 min.吸附剂最佳投加量为2.8 g/L.pH值是影响吸附过程的重要因素之一,本研究最佳反应pH范围为6.0 ～8.0.吸附等温线研究发现MgO - AC除氟剂吸附等温线方程均符合Langmuir吸附等温线模型,且吸附量随着温度的升高而升高.吸附动力学研究发现动力学数据较好的的符合伪二级动力学模型.本研究对MgO- AC除氟的机理进行了初步探讨.廉价以及较高的吸附性能等优点表明MgO - AC是一种有实际应用潜力除氟材料.