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Title: Silica supported nickel catalysts : tracer studies
Author: Sharratt, Andrew Paul
ISNI:       0000 0001 3399 9090
Awarding Body: University of Surrey
Current Institution: University of Surrey
Date of Award: 1991
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A series of silica supported catalysts were prepared by impregnation of the support materials with a nickel(II) nitrate precursor under standard conditions. The catalysts and silicas were characterised using temperature programmed reduction (TPR) techniques, neutron diffraction, small angle neutron scattering, and 29Si magic angle spinning nuclear magnetic resonance (MAS-NMR). These analyses revealed one significant variable in the silicas:- the surface concentration of strained siloxane rings containing three silicon atoms. The catalysts were tested using ethene as a probe molecule and the amination of ethanol as a test reaction in conjunction with various tracers (2H, 3H, 13C and 15N). Significant differences in behaviour and activity were observed, these differences correlated with the surface concentration of the strained three membered rings. Possible interactions between reactants and the rings were proposed to explain the observed differences in behaviour. Based on the tracer studies it was possible to propose a mechanism for the animation reaction over the catalysts. The role of the silica surfaces in influencing the activity of the catalysts was illustrated in terms of the proposed reaction mechanism.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID:  DOI: Not available
Keywords: Physical chemistry