Inorganic Chemicals Industry ›› 2021, Vol. 53 ›› Issue (6): 199-204.doi: 10.19964/j.issn.1006-4990.2020-0421

• Catalytic Materials • Previous Articles     Next Articles

Study on preparation of bentonite supported Ru catalysts and their performance for hydrogen generation from catalytic hydrolysis of ammonia borane

Chen Lingxia1(),Wang Qi1,Sun Haijie1(),Chen Zhihao2,Liu Ranran1   

  1. 1. School of Chemistry and Chemical Engineering,Zhengzhou University,Zhengzhou 450044,China
    2. Zhengzhou Tobacco Research Institute of CNTC
  • Received:2020-07-25 Online:2021-06-10 Published:2021-07-08
  • Contact: Sun Haijie E-mail:chenlingxia2120@vip.163.com;sunhaijie406@163.com

Abstract:

Ruthenium/bentonite(Ru/Ben) catalysts were prepared via an impregnation-reduction method using NaBH4 as the reducing agent.The effects of ruthenium content,amount of reducing agent of sodium borohydride,reduction temperature and reaction conditions on the hydrolysis of ammonia borane(NH3BH3) catalyzed by Ru/Ben were investigated.The results showed that under the conditions of Ru loading of 0.3%(mass fraction),the molar ratio of Ru to NaBH4 was 1∶2.5,and the reduction temperature was 303 K,the size of Ru microcrystalline in Ru/Ben was 3.8 nm,and the conversion frequency(TOF) of Ru/Ben catalyzed hydrolysis of NH3BH3 was 145 mol/(mol·min).When the stirring speed reached 450 r/min,external diffusion could be neglected,resulting in the highest reaction rate towards hydrogen generation.The rate of hydrogen production was directly proportional to the concentration of Ru/Ben.The interfacial reaction of catalyst was the decisive step in the hydrolysis of NH3BH3 to generate hydrogen.The order of Ru/Ben catalyzed hydrolysis of NH3BH3 to generate hydrogen was 0.7.The higher the reaction temperature,the higher the mass transfer rate of ammonia borane to the catalyst surface,the easier desorption of hydrogen and sodium metaborate from the catalyst surface,and the higher the hydrogen generation rate.The kinetic calculation showed that the hydrogen production rate of NH3BH3 hydrolysis catalyzed by Ru/Ben was independent of the concentration of aminoborane,and the activation energy was 15 kJ/mol.

Key words: Ru, bentonite, ammonia borane, hydrogen generation

CLC Number: