Kinetic models of concentrated NaBH4 hydrolysis

• Published in: International journal of hydrogen energy Vol. 39; no. 1; pp. 442 - 448
• Main Authors: LIN YU, PELLECHIA, Perry, MATTHEWS, Michael A
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier 01.01.2014
• Subjects: Alternative fuels. Production and utilization; Applied sciences; Energy; Exact sciences and technology; Fuels; Hydrogen; Hydrogen-based energy; Hydrolysis; Liquids; Mathematical models; Power law; Reaction kinetics; Sodium; Hydrolysis; Hydrogen; Self-hydrolysis; Kinetic models; Kinetics; Sodium borohydride; Hydroborates; Concentrated solution
• ISSN: 0360-3199; 1879-3487
• DOI: 10.1016/j.ijhydene.2013.10.105

The hydrolysis of NaBH4 in liquid solution has been extensively studied in the past few years; however, data on the kinetics of self-hydrolysis in concentrated solution are few. This work reports the kinetic modeling of self-hydrolysis of 10a20 wt.% NaBH4 at 25a80 degree C. Also, pH data were obtained independently of the reaction kinetics data. The data obtained from Boron-11 NMR measurements and pH are used to determine kinetic parameters. An empirical power law model is evaluated over a wide pH range. The effects of temperature, pH and initial sodium borohyride concentration are reported. The power law model reproduced the trends of the kinetics of the hydrolysis reaction. In addition, a pseudo first order model derived from a proposed reaction mechanism is evaluated. The behavior of the pseudo first order rate constant k is interpreted in terms of the effect of pH.