Jyothi, T M; Dr.Sugunan, S(Cochin University of Science and Technology, January , 1999)
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Abstract:
A comparative study of acid-base properties and catalytic activity of Sn-La and
Sn-Sm mixed oxides and their corresponding sulfate modified analogues are
reported in this thesis. The catalytic activity and product selectivity in the
decomposition of alcohols are correlated with the acid-base and redox properties
of the catalyst systems under study The effect of catalyst preparation,
pretreatment and various reaction parameters on the catalytic activity of sulfate
modified oxides is investigated in the oxidative dehydrogenation reactions The
experimental conditions are optimised to synthesise industrially important organic
chemicals viz. 2,6 xylenol, o-cresol, N-methylanilne and N,N-dimethylaniline
employing the mixed oxide systems. The effect of sulfate treatment on the
catalytic activity of these systems in the alkylation reactions of phenol, anisole and
aniline is also investigated and the merits and demerits of sulfate treatment are
highlighted.
Description:
Department of
Applied Chemistry, Cochin University of Science and Technology,
Nishamol,Kanat; Sugunan, S(Department of applied chemistry, 2002)
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Abstract:
In recent years considerable advances have been achieved in the study of the surface structure and mechanism of action of environmentally benign heterogeneous catalysts. The study entitled as surface properties and catalytic activity of manganese ferrospinels. In the present study we have prepared manganese ferrospinels of general formula Mn(1-x)BxFe2O4 via low temperature controlled co-precipation method. The study employed low temperature co-precipitation method for the preparation ofMn(1-x)BxFe2O4 specimens, where B is a metal cation such as Cr,Co, Ni,Cu and Zn. The catalytic activities of the systems were investigated for liquid-phase benzoylation of aromatic compounds and phenol hydroxylation and for vapour-phase reactions such as aniline alkylation, phenol methylation and ODH of ethylbenzene. The different series of manganese ferrites are proved to be excellent catalysts for various industrially important reactions such as Friedel-crafts benzoylation of aromatic compounds, methylation of aniline and phenol, hydroxylation of phenol and oxidative dehydrogenation of ethylbenzene. Due to the tightening of the environmental regulations, production of diphenols from phenol hydroxylation and reduction of phenolic pollutants in waste waters using these catalysts can be a promising approach because it demands only simple techniques and produce little environmental pollution.