Journal of Inorganic Materials ›› 2016, Vol. 31 ›› Issue (1): 14-20.DOI: 10.15541/jim20150295

• Orginal Article • Previous Articles     Next Articles

Chemical Kinetics of Disproportionation Decomposition of tert-Butyl Hydroperoxide Catalyzed by Buserite-type Manganese Oxides

LU Shu-Pei1, FENG Li-Li2, QI Lin1, WANG Li-Li2, QI Xing-Yi1   

  1. (1. School of Chemistry and Environment, Beihang University, Beijing 100191, China; 2. Key Laboratory of Urban Stormwater System and Water Environment of Ministry of Education, Beijing University of Civil Engineering and Architecture, Beijing 100044, China)
  • Received:2015-06-29 Revised:2015-09-09 Published:2016-01-20 Online:2015-12-15
  • About author:LU Shu-Pei. E-mail: sigmalsp@buaa.edu.cn

Abstract:

The series of four buserite-type layered manganese oxides (Me-buserites) with different interlayer cations (Me, Me = Mg2+, Co2+, Ni2+, Cu2+) were synthesized by using both MnSO4·H2O as Mn source and K2S2O8 as oxidant. The as-synthesized Me-buserites were characterized by X-ray diffraction (XRD), inductively coupled plasma-atomic emission spectrometry (ICP-AES) and N2 adsorption-desorption (BET), in order to determine their crystal phases, elemental compositions and specific surface areas, respectively. In a 25 mL batch glass reactor, the disproportionation decomposition of tert-butyl hydroperoxide was kinetically investigated with the above Me-buserites as catalysts. The kinetic analyses show that the rate law established herein is second order in tert-butyl hydroperoxide, first order in Me-buserites and then third order overall, and that the apparent activation energy ranges from 56 kJ/mol to 125 kJ/mol. In accordance with the kinetic fittings, the proposed mechanism comprises two elementary reaction steps: pre-equilibrium step and rate-determining step. In terms of the pseudo-second-order rate constant and the half an hour-accumulated O2 volume (both obtained at 338 K), the activity follows the order of Cu-buserite > Mg-buserite > Ni-buserite > Co-buserite. And a 100% selectivity towards tert-butyl alcohol is achieved over all the Me-buserites under selected reaction conditions.

Key words: buserite-type layered manganese oxides, tert-butyl hydroperoxide, tert-butyl alcohol, disproportionation decomposition, chemical kinetics

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