Adsorption Behavior of Rhodamine B on UiO-66

The adsorption characteristics of UiO-66 (a Zr-containing metal-organic framework formed by terephthalate) for Rhodamine B (RhB), such as isotherms, kinetics and thermodynamics, were investigated systematically. The batch adsorption data conform well to the Langmuir and Freundlich isotherms. The adsorption kinetics of UiO-66 for RhB can be well described by the pseudo first-order model, and the adsorption thermodynamic parameters Delta G(0), Delta H-0 and Delta S-0 at 273 K are -6.282 kJ.mol(-1), 15.096 kJ.mol(-1) and 78.052 J.mol(-1).K-1, respectively. The thermodynamic analyses show that the adsorption process of RhB on UiO-66 is more favorable at higher temperatures. UiO-66 can be regenerated by desorbing in DMF solution with ultrasonic for 1 h. UiO-66 can keep good performance for at least six cycles of sorption/desorption. (C) 2014 The Chemical Industry and Engineering Society of China, and Chemical Industry Press. All rights reserved.