文献类型：期刊文献

英文题名：Reaction mechanism and kinetics for hydrolytic dehydrogenation of ammonia borane on a Pt/CNT catalyst

作者：Chen, Wenyao[1]; Li, Dali[1]; Wang, Zijun[1]; Qian, Gang[1]; Sui, Zhijun[1]; Duan, Xuezhi[1]; Zhou, Xinggui[1]; Yeboah, Isaac[2]; Chen, De[2]

机构：[1] State Key Laboratory of Chemical Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China; [2] Dept. of Chemical Engineering, Norwegian University of Science and Technology, Trondheim, 7491, Norway

年份：2017

卷号：63

期号：1

起止页码：60

外文期刊名：AIChE Journal

收录：EI(收录号：20165003125157)

语种：英文

外文关键词：Ammonia - Dehydrogenation - Reaction kinetics - Catalysts - Chemical bonds - Thermoanalysis - Byproducts

摘要：A reaction mechanism is proposed for hydrolytic dehydrogenation of ammonia borane on a Pt/CNT catalyst. A combination of thermodynamic analysis and FTIR measurement reveals that B-containing byproducts are mainly in the form of an NH4B(OH)4-B(OH)3 mixture rather than NH4BO2 reported previously. The revised main reaction is NH3BH3+4H2O →NH4B(OH)4 + 3H2↑ involving the B–H, B–N, and O–H bond cleavages. Isotopic experiments using D2O instead of H2O as reactant or introducing D2 into the reaction atmosphere suggest the O–H bond cleavage being in the rate-determining step, and an unfavorable occurrence of the chemisorbed H2O dissociation (i.e., the direct O–H bond cleavage), respectively. Different reaction pathways with indirect O–H bond cleavages are analyzed, and then NH3BH3+4H2O* NH3BH2(OH)* +H* is suggested as the rate-determining step. Subsequently, a Langmuir–Hinshelwood kinetic model is developed, which fits well with the experimental data. ? 2016 American Institute of Chemical Engineers AIChE J, 63: 60–65, 2017. ? 2016 American Institute of Chemical Engineers