Mustafa S, Nawab G, Naeem A, Rehana N, Dilara B
National Centre of Excellence in Physical Chemistry, University of Peshawar, Peshawar, Pakistan.
Environ Technol. 2004 Jan;25(1):1-6. doi: 10.1080/09593330409355432b.
The ion exchange sorption of phosphate on Fe(OH)3 is studied as a function of temperature (25-55 degrees C) and concentration (1.49-3.23 mmol l(-1)). The mechanism of sorption is observed to be the exchange of OH- anions from the adsorbent surface by those of H2PO4- and HPO4(2-) from the aqueous solution. An equation developed in the Langmuir formalism is used to explain the ion exchange sorption of phosphate on Fe(OH)3. The isosteric heat of sorption illustrates that the uptake of phosphate on Fe(OH)3 takes place through an anion exchange process, involving both the phosphate anions H2PO4- and HPO4(2-). Further, at higher temperature the solid prefers the HPO4(2-) anions forming a binuclear bridging complex.
研究了磷酸盐在Fe(OH)₃上的离子交换吸附作用与温度（25 - 55摄氏度）和浓度（1.49 - 3.23 mmol l⁻¹）的关系。观察到吸附机理是吸附剂表面的OH⁻阴离子与水溶液中的H₂PO₄⁻和HPO₄²⁻阴离子发生交换。用朗缪尔形式推导出的一个方程来解释磷酸盐在Fe(OH)₃上的离子交换吸附。吸附等温热表明，磷酸盐在Fe(OH)₃上的吸附是通过阴离子交换过程进行的，涉及磷酸根阴离子H₂PO₄⁻和HPO₄²⁻。此外，在较高温度下，固体更倾向于HPO₄²⁻阴离子形成双核桥连络合物。
