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An activated alumina-supported iron oxide-composite (denoted as FeAA-25) was utilized successfully as a catalyst for the heterogeneous photoassisted Fenton degradation of the azo dye C.I. Reactive Black 5 (RB5) at a pH of 7.0 in our previous study. In this work, the adsorption and desorption behaviours of RB5 on FeAA-25 were studied. Adsorption thermodynamics of RB5 on FeAA-25 were studied at 288, 303 and 318K and the thermodynamic parameters, such as equilibrium constant , standard free energy changes , standard enthalpy change and standard entropy change have been obtained. A pseudo-second-order rate model was employed to describe the kinetic adsorption processes. Additionally, desorption studies revealed that RB5 can be easily removed from FeAA-25 by altering the pH of the solution using NaOH. The mechanism of the RB5 adsorption onto FeAA-25 at neutral pH 7.0 will be established through this study. [Copyright &y& Elsevier]

Abstract: Hydrolysis of sodium borohydride (NaBH4) is a promising method for on-board hydrogen supply to polymer electrolyte membrane fuel cells (PEMFC). This article presents an attempt to design a novel solid-state NaBH4 composite, which is made up of NaBH4 powder, Co2+/IR-120 catalyst and silicone rubber, for hydrogen generator. The silicone rubber can act as a stabilizer in the solid-state NaBH4 composite because of its surface hydrophobicity leading to reduced diffusion rate of water into the composite. The solid-state NaBH4 composite can produce hydrogen stably near 25mLmin−1 for at least 2h without employment of any mechanical control system. Using the hydrogen generated from the solid-state NaBH4 composite, a 2W PEMFC stack is successfully operated to power a cellular phone. [Copyright &y& Elsevier]