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Provides information on a study which examined the vapor phase alkylation of phenol with a series of alcohols containing different number of carbons. Details on the experiment; Results and discussion; Conclusion.

Vapor phase alkylation of phenol with methanol was carried out over catalysts derived from a series of hydrotalcite (HT)-like compounds of the form M(II)Al-HT; where M(II)=Mg, Mn, Co, Ni, Cu and Zn with M(II)/Al atomic ratios of2-5. The kinetic parameters such as rate constant (k), apparent activation energy (E) and Arrhenius frequency factor (A) for the disappearance of phenol were evaluated employing a power law equation assuming pseudo-first order kinetics. The kinetic parameters were found to be in good agreement with phenol conversion. The existence of the compensation effect between E and ln A was tested. [ABSTRACT FROM AUTHOR]

The trans-dioxo ruthenium (VI) complex, [P(CH)CHCH][Ru(O)OAcCl] or tetrapropylammonium perruthenate catalyzes the oxidation of secondary alcohols to ketones by N-methylmorpholine- N-oxide (NMO). Kinetic studies showed the formation of a complex between catalyst and substrate (alcohol) as the first step in the mechanism. [ABSTRACT FROM AUTHOR]

RuX(DMSO) (X=Cl, cis; Br, trans) undergoes ligand substitution in N,N-dimethylformamide (DMF) to give RuX(DMSO)DMF, which catalyzes the oxidation of secondary alcohols by NMO to ketones. Kinetics of the reaction catalyzed by trans-RuBr(DMSO) differed from that of cis-RuCl(DMSO). A mechanism is proposed involving the formation of Ru(IV)oxo species as the active intermediate and a rate expression is derived. [ABSTRACT FROM AUTHOR]

A series of cobalt containing hydrotalcites having the general formula CoMCO3-HT where M = Al, Fe and Cr were synthesized by sequential and coprecipitation methods. The samples were primarily characterized by X-ray diffraction (XRD), infrared absorption studies, transmission electron microscopy-energy dispersive X-ray analysis (TEM-EDAX), thermogravimetry-differential scanning calorimetry (TG-DSC) and BET surface area measurements. The lattice parameters, FTIR stretching wavelengths for O–H bonds and thermal stability depended on the ionic radius of the trivalent M cation. Thermal calcination of these materials yielded a non-stoichiometric spinel-type phase whose crystallinity was also affected by the nature of the trivalent cation. [ABSTRACT FROM AUTHOR]