Das J, Sairam Patra B, Baliarsingh N, Parida K M
Institute of Minerals and Materials Technology (IMMT) (Formerly Regional Research Laboratory), Bhubaneswar 751 013, Orissa, India.
J Colloid Interface Sci. 2007 Dec 15;316(2):216-23. doi: 10.1016/j.jcis.2007.07.082. Epub 2007 Aug 10.
Mg-Fe-CO(3) layered double hydroxide (LDH) with a Mg/Fe molar ratio of 2.0 was synthesized by co-precipitation method and its calcined product (CLDH) was obtained by heating Mg/Fe-LDH at 500 degrees C. Sorption of SeO(2-)(3) on CLDHs was studied and the results indicate that the sorption capacity of CLDHs was higher than that of uncalcined LDHs. Isotherms for SeO(2-)(3) sorption by CLDHs were well described using the Freundlich and Langmuir equations. The thermodynamic parameters, viz. DeltaG*, DeltaH*, DeltaS* were calculated to predict the nature of adsorption. The negative and positive values of DeltaG* and DeltaH* indicate that the adsorption process is spontaneous and endothermic in nature, respectively. The adsorption process followed first-order kinetics.
通过共沉淀法合成了镁铁摩尔比为2.0的碳酸镁铁层状双氢氧化物（LDH），并通过在500℃下加热镁铁LDH得到其煅烧产物（CLDH）。研究了CLDH对亚硒酸根（SeO₂⁻₃）的吸附，结果表明CLDH的吸附容量高于未煅烧的LDH。用Freundlich和Langmuir方程很好地描述了CLDH对SeO₂⁻₃的吸附等温线。计算了热力学参数，即ΔG*、ΔH*、ΔS来预测吸附性质。ΔG的负值和ΔH*的正值分别表明吸附过程本质上是自发的和吸热的。吸附过程遵循一级动力学。
