The Kinetics of an Interfacial Reaction in a Microemulsion

Abstract

We propose an interfacial reaction model describing the kinetics of the synthesis of 1-phenoxyoctane from 1-bromooctane and sodium phenoxide in a nonionic microemulsion. In this model the microemulsion is divided into the aqueous and the organic subvolume. The interface is covered by a monolayer of surfactant molecules. The interfacial area is determined by the concentration of surfactant in the microemulsion. The reaction is assumed to take place only at the internal interface of the microemulsion. Due to the nanometer dimensions of the microemulsion droplets it is also assumed that there is no concentration gradient between the core of the droplets and the internal interface. Therefore, bulk concentrations of the reactants within the subvolumes are used for the kinetic evaluation of the obtained data. The model proves to be valid for the complete range of variations of the microemulsion composition studied here.

Use of self-assembled surfactant systems as media for a substitution reaction

“…A similar reaction, between sodium phenolate and decyl bromide, has been investigated in a microemulsion based on a nonionic surfactant and a model for the kinetics has been put forward [14,15]. A similar kinetics expression has been worked out for the related reaction between tert-butylbenzyl bromide and potassium iodide [16].…”

“…The aim of the present work was to investigate in a systematic manner nucleophilic substitution reactions between phenolate ions of varying hydrophobicity (and surface activity) and 3-bromo-1-propanol as substrate. The reaction can be expected to be a typical S N 2 reaction [14,15], i.e., a one-step reaction in which the rate depends on the concentrations of both the nucleophile and the substrate. Reactions were performed in micellar systems and in microemulsions, both based on either a nonionic or a cationic surfactant.…”

Rhodium catalyzed hydroformylation of 1-octene in microemulsion: comparison with various catalytic systems

“…One useful way to overcome this solubility problem that is frequently encountered in organic reactions is performing the reaction in a microemulsion [8,9]. A microemulsion is formed by adding a suitable surfactant to biphasic system.…”