摘要
针对水体中低浓度磷深度净化问题,以过氧化钙为吸附剂,采用等温吸附、吸附热力学模型和吸附动力学模型的方法开展其对磷酸盐吸附特性的研究,讨论p H、共存阴离子对其除磷过程的干扰能力.结果表明:(1)过氧化钙对磷酸盐的吸附等温线方程符合Langmuir方程,过氧化钙对磷酸盐的最大吸附量为381.7 mg/g(25℃);(2)过氧化钙在除磷过程中系统的热力学参数ΔG0<0,ΔH0<0,即过氧化钙对磷的吸附作用是一个自发的放热过程;(3)二级反应速率方程可精准地描述过氧化钙的吸附行为,其吸附速率随着溶液中磷酸盐浓度的升高而升高,经过4 min即可达到吸附平衡;(4)过氧化钙在p H=8时除磷效果达到最佳;(5)高浓度倍数的共存阴离子中,CO2-3对过氧化钙除磷影响最大,在10倍浓度下可造成吸附量减少14.7%.
Aiming at the advanced purification of low concentration of phosphorus in natural water, the adsorption of phosphate by CaO2 was studied using the models of adsorption kinetics and adsorption isotherm, and the influence of different operating parame-ters on the phosphorus removal was investigated. The results showed that：（1） The experimental data for the process of phosphate uptake onto CaO2 fit the Langmuir isotherm mode, and the maximum adsorption capacity was 381. 7 mg/g （25℃）. （2） Thermo-dynamic parameters in the process of phosphorus removal areΔG0 ＆lt;0 andΔH0 ＆lt;0, while the process was a spontaneous exother-mic one. （3） The adsorption performance of CaO2 was evaluated by the pseudo-second-order reaction rate equation, when the ad-sorption rate increased with the increasing concentration of phosphate in the solution, and the adsorptive reaction reached equilibri-um in 4 minutes. （4） The optimized effect of phosphorus removal was obtained at pH=8. （5） Among the high concentrations of coexisting anions, the CO2-3 expressed the greatest influence on phosphorus removal of CaO2 and could make the adsorption capaci-ty reduce 14. 7% under the concentration of 10 times.
出处
《湖泊科学》
EI
CAS
CSCD
北大核心
2015年第3期493-501,共9页
Journal of Lake Sciences
基金
国家水体污染控制与治理科技重大专项(2012ZX07103)资助
