EQUILIBRIUM, KINETIC, AND THERMODYNAMIC ANALYSIS OF Cd(II) SORPTION FROM AQUEOUS SOLUTIONS USING POLYMERIC MICROCAPSULES CONTAINING AN ACIDIC ORGANOPHOSPHONIC EXTRACTANT

作者：Valenzuela Fernando^*; Valdes Andrea; Ide Viviana; Basualto Carlos; Sapag Jaime; Araneda Claudio

来源：Solvent Extraction and Ion Exchange, 2012, 30(4): 422-430.

DOI：10.1080/07366299.2012.687180

• Cadmium(II)
• microcapsules
• sorption
• equilibrium
• kinetics
• thermodynamics

The equilibrium, kinetics, and thermodynamics of Cd(II) sorption from aqueous solutions onto polymeric microcapsules has been studied. Microcapsules were prepared by immobilizing an acidic organophosphonic extractant in a polymeric matrix prepared from styrene and ethylene glycol dimethacrylate following in situ free-radical suspension polymerization. Scanning electronic microscopy showed that the microcapsules were spherical and exhibited a rough surface with an average BET surface area of 12-20 m(2) g(-1) and an approximate pore size of 7.0 nm. The microcapsules were contacted with aqueous solutions containing Cd(II) approximately 100 mg L-1 at an initial pH = 4.0 to study their sorptive behaviour over a temperature range of 293-323 K. The results of equilibrium experiments showed that the results filled the Langmuir isotherm model. The experimental kinetics followed a pseudo-second order model with an activation energy of 47.1 +/- 2.2 kJ mol(-1). Thermodynamics measurements showed that sorption is spontaneous and exothermic and that entropy had a negative value.

• 出版日期2012