Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China.
Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China.
J Environ Sci (China). 2018 Feb;64:335-344. doi: 10.1016/j.jes.2017.06.034. Epub 2017 Jul 5.
For the removal of phosphate (PO) from water, an adsorbent was prepared via carbonization of sewage sludge from a wastewater treatment plant: carbonized sludge adsorbent (CSA). The mechanism of phosphate removal was determined after studying the structure and chemical properties of the CSA and its influence on phosphate removal. The results demonstrate that phosphate adsorption by the CSA can be fitted with the pseudo second-order kinetics and Langmuir isotherm models, indicating that the adsorption is single molecular layer adsorption dominated by chemical reaction. The active sites binding phosphate on the surface are composed of mineral particles containing Si/Ca/Al/Fe. The mineral containing Ca, calcite, is the main factor responsible for phosphate removal. The phosphate removal mechanism is a complex process including crystallization via the interaction between Ca and PO; formation of precipitates of Ca, Al, and PO; and adsorption of PO on some recalcitrant oxides composed of Si/Al/Fe.
为了从水中去除磷酸盐（PO），通过碳化来自污水处理厂的污泥制备了一种吸附剂：碳化污泥吸附剂（CSA）。研究了 CSA 的结构和化学性质及其对磷酸盐去除的影响，确定了磷酸盐去除的机理。结果表明，CSA 对磷酸盐的吸附可以用伪二阶动力学和 Langmuir 等温线模型拟合，表明吸附是由化学反应主导的单分子层吸附。表面结合磷酸盐的活性位点由含有 Si/Ca/Al/Fe 的矿物颗粒组成。含 Ca 的矿物，方解石，是去除磷酸盐的主要因素。磷酸盐去除机制是一个复杂的过程，包括 Ca 和 PO 之间的相互作用结晶；形成 Ca、Al 和 PO 的沉淀物；以及 PO 在由 Si/Al/Fe 组成的一些难降解氧化物上的吸附。
