通过小试振荡实验,研究了经573℃热改性的颗粒状石英砂(热改性砂)对水中低浓度磷的吸附效果.对原砂和热改性砂的XRD图谱分析,验证了石英砂的同质异晶转变.研究结果表明,实验时段内热改性砂对水中低浓度磷(1mg/L)的去除率达到99%,磷吸附动力学和等温吸附实验结果可分别由准二级反应动力学模型和Langmuir吸附等温线非线性模拟,相关系数R^2均大于0.95.25℃时,热改性砂最大吸附容量(qm)为0.71 mg/g(磷/吸附剂),D-R吸附模型计算的吸附平均自由能E=7.21kJ/mol,物理吸附为优势吸附行为.热改性颗粒状石英砂吸附除磷实现了不引入二次污染的除磷过程,拓宽了颗粒状石英砂在水处理中的应用,为再生水中磷的去除提供了理论支持.
Removal of phosphate from stimulated reclaimed water using high temperature calcinated granular sand(573-quartz-sand)at 573℃ was investigated by batch experiments.Verified the allomorphic transformation of quartz sand through the comparison of both the raw quartz sand and573-quartz-sand's XRD spectrums.The efficiency of phosphate removal achieved 99% in entire adsorption time.The data obtained from kinetics and isotherm experiments could be well fitted by the pseudo-second-order rate model and Langmuir isotherm respectively.Both the linear correlation coefficients were higher than 95%.The theoretical saturated capacity(qm)was=0.71mg/g at 25℃.D-R isotherm model could decribe those data and derived mean free energy E,which was equal to7.21kJ/mol.Secondary-pollution wasn't been adhibitted in the adsorption process and this results will extend the application of granular quartz-sand and provide technical guidance for phosphate removal from reclaimed water in the future.