Adsorption of arsenic(III) into modified lamellar Na-magadiite in aqueous medium—Thermodynamic of adsorption process |
| |
Authors: | Denis Lima Guerra Alane Azevedo Pinto Rúbia Ribeiro Viana |
| |
Institution: | a UNICAMP, Instituto de Química, Universidade Estadual de Campinas, Cp 6154, 13083-9700 Campinas, SP, Brazil b UFMT, Universidade Federal de Matogrosso, Centro de Recursos Minerais, Cuiabá, Matogrosso 68060 900, Brazil |
| |
Abstract: | Synthetic Na-magadiite sample was used for organofunctionalization process with N-propyldiethylenetrimethoxysilane and bis3-(triethoxysilyl)propyl]tetrasulfide, after expanding the interlayer distance with polar organic solvents such as dimethylsulfoxide (DMSO). The resulted materials were submitted to process of adsorption with arsenic solution at pH 2.0 and 298±1 K. The adsorption isotherms were adjusted using a modified Langmuir equation with regression nonlinear; the net thermal effects obtained from calorimetric titration measurements were adjusted to a modified Langmuir equation. The adsorption process was exothermic (ΔintH=−4.15-5.98 kJ mol−1) accompanied by increase in entropy (ΔintS=41.32-62.20 J k−1 mol−1) and Gibbs energy (ΔintG=−22.44−24.56 kJ mol−1). The favorable values corroborate with the arsenic (III)/basic reactive centers interaction at the solid-liquid interface in the spontaneous process. |
| |
Keywords: | Chemical properties Nanocomposites Surfaces Interfaces |
本文献已被 ScienceDirect 等数据库收录! |
|