经三氯化铁改性的沸石除磷效果

Effect of Phosphorus Removal by Zeolite Modified by Ferric Trichloride

为提高沸石填料的除磷效果,用Fe Cl3沉积法,改性粒径为10~20目的天然沸石,研究沸石的最佳改性条件,以及反应时间、进水磷浓度和沸石投加量等对除磷效果的影响。研究结果表明,经Fe Cl3改性的沸石的除磷率是天然沸石的6.2~12.8倍,最佳改性摩尔质量浓度为3.5 mol/L;当进水磷质量浓度为10 mg/L时,改性沸石最佳投加浓度为0.1 g/m L,其除磷率随着时间增加而增大,在8 h后趋于稳定;随着进水磷浓度的增大,改性后的沸石的吸附速率和吸附容量增大,其吸附速率符合班厄姆公式;改性沸石等温吸附过程符合Freundlich方程(R2>0.988)和Langmuir方程(Qm=0.275 6 mg/g,R2>0.988)。

In order to improve the phosphorus removal capacity of zeolite, FeCl3 sedimentation method was used to modify the natural clinoptilolite with particle size of 10-20 mesh. After the modification, phosphorus removal test was carried out to explore the best conditions of modification and the influence of reaction time, inffiuent concentration of phosphorus and dosage of clinoptilolite on phosphorus removal capacity. The results showed that the removal capacities of phosphorus by modified zeolite were 6.2 to 12.8 times that of the natu- ral zeolite and the best modification conditions of FeCl3 was 3.5 mol/L. The best dosage of modified zeolite was 0.1 g/mL when the inffiuent concentration of phosphorus was 10 mg/L. The phosphorus removal capacity improved with the increasing reaction time then kept constant after 8 h. In addition, the absorption rate and ca- pacity also increased with the increasing inffiuent concentration of phosphorus. The absorption rate followed Bangham formula with the characteristics of fast adsorption and slow balance. The absorption process could be described by both Freundlich equation （R2〉0.988） and Langmuir equation （Qm=0.275 6 mg/g, R2〉0.988）.