General Kinetic Model for Liquid−Liquid Phase-Transfer-Catalyzed Reactions

Abstract

A simple and fairly general kinetic model framework for analyzing the rate data for phasetransfer catalysis reactions has been developed. The model does not a priori assume extractive equilibrium and applies equally well to cases where the pseudo steady state with respect to the active catalytic species in one of the phases is not maintained. Within this framework, complex multistep reactions of comparable rates in both phases along with interphase mass-transfer resistance, if and when present, can be considered. The model was applied to interpret published kinetic data for a number of phase-transfer and inverse phase-transfer catalysis reactions. The model is likely to be useful in rationalizing published or new kinetic data from a general and unified framework and will contribute to the design and development of reactors carrying out phase-transfer catalysis reactions of industrial importance. † NCL Communication No. 6331. ‡ Fax Nos.: (0212) 330233 and (0212) 334761.

Phase transfer catalysis: Chemistry and engineering

“…Experimental data on QY concentration profiles with time Yang, 1990, 1991a) validate these model predictions. Bhattacharya (1996) has proposed that a quasi-stationary concentration of quat species in the organic phase arises only when the rate of delivery of the nucleophile to the organic phase is almost exactly balanced by its consumption in the organic reaction. When the rate of consumption is faster than the rate of quat transport, the concentration in the organic phase falls.…”

“…Using information from items 1-5 above, the overall kinetics of the PTC cycle in a liquid-liquid system can be characterized. However, due to the complex multistep mechanism of PTC, various approaches to LLPTC modeling have been taken (Bhattacharya, 1996;Chen et al, 1991;Wu. 1993;Melville and Goddard, 1988;Evans and Palmer, 1981).…”

Experimental validation of equilibrium based mathematical modelling of liquid‐liquid phase transfer catalysis

“…In this model as well, the species in the aqueous phase are assumed to be in equilibrium. Hence the species concentration in the aqueous phase is described by Equations (10)(11)(12)(13)(14)(15)(16)(17).…”

“…Maity et al developed a mechanistic kinetic model assuming equilibrium of phase transfer catalyst and active catalyst at the interface. Bhattacharya and Bhattacharya and Mungikar developed a mathematical model assuming different species in the aqueous phase to be in equilibrium. They considered the reaction to occur in both the organic phase and the film region.…”

Phase transfer catalyzed esterification: modeling and experimental studies in a microreactor under parallel flow conditions

“…Despite many publications on the chemistry and applications of PTC, only few of them involve the role of interfacial mass transfer and mathematical modeling which include reaction kinetics in both phases and mass transport between and within each phase (Wang and Wu 1990;Asai et al 1993;Wu 1993;Wang and Chang 1994;Bhattacharya 1996;Yang 1998).…”