Adsorption Study of Glycerol in Biodiesel on the Sulfonated Adsorbent

作者：Chen, Bin; Wang, Wusheng; Liu, Xiao; Xue, Weiming; Ma, Xiaoxun; Chen, Guoliang; Yu, Qiushuo; Li, Rong^*

来源：Industrial & Engineering Chemistry Research, 2012, 51(39): 12933-12939.

DOI：10.1021/ie301951p

• AQUEOUS-SOLUTION
• PURIFICATION
• EQUILIBRIUM
• REMOVAL
• SEPARATION
• IONS
• THERMODYNAMICS
• EXCHANGER
• ACIDS
• LEAD

The adsorption isotherm data of glycerol from biodiesel (FAME, fatty acid alkyl esters) onto the sulfonated adsorbent were obtained via batch equilibrium tests at different temperatures in the range of 303-323 K. Subsequently, these data were fitted by four isotherm models. Freundlich isotherm model was the best fitted (r(2) > 0.98), and the model parameter 1/n implied that the adsorption process was favorable. For the Dubinin-Radushkevich (D-R) isotherm model, the model parameter Q(D) decreased with increasing temperature, and the mean free energy of sorption (E) was less than 8 kJ mol(-1). The results of Q(D) and E reflected the exothermic and physical properties of the adsorption process, respectively. The negative values of Gibbs free energy change (Delta G(0)) and enthalpy change (Delta H-0) indicated that the adsorption occurs spontaneously with an exothermic nature, while the positive values of entropy change (Delta S-0) suggested the increase in randomness at the solid-liquid interface during adsorption. The isosteric heat of adsorption (Delta H-x) suggested that strong hydrogen bonding between glycerol and the -SO3- groups of the sulfonated adsorbent dominated the adsorption process and that there existed adsorbate-adsorbate mutual attractive interaction. Furthermore, the existence of hydrogen bonding was also confirmed by infrared spectra.

• 出版日期2012-10-3
• 单位西北大学