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Kinetic study for the heterogeneous decomposition of hydrogen peroxide over different non-soluble metal oxides (CuO, Fe2O3 and PbO2) was taken as a model reaction, mainly in normal micellar, inverse micellar microemulsion of sodium dodecyl sulfate (SDS). Other micellar phases of different surfactants [sodium dioctylsulfosuccinate (AOT), cetyle trimethyl ammonium bromide (CTAB) and triton X100] have been studied. Different organic solvents have been investigated. A promotional effect was generally observed. The reaction rate determining step was estimated. Reaction rate constants and thermodynamic parameters (ΔG*, ΔH* and ΔS*) were calculated. It was found that the highest promotional influence was observed in the case of (SDS/Fe3O4) in micellar and inverse micellar micro-emulsion media.

The reaction kinetics of ninhydrine (Nin) with glycine-glycine di peptide (Gly) was studied in aqueous solution. The same reac tion was studied in micellar solutions of different surfactants such as sodium dioctylsulfosuccinate (AOT) and sodium dodecyl sulfate (SDS). The reaction was also studied in the L2 micro emulsion phase of the three systems AOT/heptane/water, SDS/ pentanol/heptane/water, CTAB/pentanol/heptane/water. Spectrophotometric measurements were perfomed at 570 nm. The data show that the reaction is first-order with respect to Nin and Gly in all cases. Values of the observed rate constants (kobs) increase with increasing concentration of the surfactant in micel lar media. AOT was more promotional than SDS. The reaction rate in the presence of different micelles could be explained using a pseudo-phase kinetic model. Association constants of Nin and Gly with surfactant micelles are reported. Values of kobs for the reaction rates in the microemulsion phases are reported. AOT/heptane L2 microemulsion system has been clearly found as the most promotional among all the other studied systems. Association constants of Nin and Gly with surfactant in micro emulsion were obtained. The rate was increased with the tem perature in aqueous, micellar and microemulsion phases. The activation parameters AH*, AS* and AG* have also been obtained. The reaction rate in different microemulsion media is slightly in creased with the change of oil (heptane > hexane > pentane), while co-surfactants (butanol, pentanol and hexanol) have no effect on kobs values in AOT, CTAB or SDS microemulsion.

Adsorption of different n-alkyl alcohols (hexanol, pentanol, butanol, propanol, ethanol and methanol) out of aqueous media by polyurethane foam, an insulation waste powder, (PUF) was investigated using batch system under controlled conditions. Kinetic data followed more closely to the pseudo-first-order model. The adsorption rate and the related parameters, such as the PUF dosage, n-alkyl alcohol initial concentration, pH, temperature, and ionic strength were studied. The saturation equilibrium was also studied as a function of the related parameters (PUF dose, alcohol initial concentration, temperature, pH and ionic strength). The adsorption isotherm was established for the adsorption of different alcohols on PUF. Linearized Langmuir, Freundlich and Frumkin models were applied to estimate the adsorption constants. It was estimated that the adsorption rate is positively affected by increasing PUF dose, adsorbent concentration, acidity and temperature. The adsorption equilibrium was shifted toward higher adsorption capacity by increasing the PUF dose, substrate concentration, temperature and acidity in the order of: n-hexanol > n-pentanol > n-butanol > n-propanol > ethanol > methanol. It was not affected by ionic strength. The adsorption data fit to Freundlich, Langmuir and Frumkin models, but attained a better correlation to models in the order of as Langmuir > Freundlich > Frumkin. In addition to the Freundlich, Langmuir und Frumkin constants the thermodynamic parameters of activation and adsorption were determined.

Kinetic study concerning the complex formation of silver ion (Ag +) with Ortho-aminobenzoic acid(OABA) was conducted. The reaction kinetics was studied in aqueous, micellar solutions and L2 microemulsion media of different surfactants. Sodium dioctylsulfosuccinate (AOT), cetyltrimethylammonium bromide (CTAB) and sodium dodecyl sulfate (SDS) were the studied surfactants. Spectrophotometric study follow up at 460 nm was used. The results show that the reaction is first-order with respect to Ag + and OABA in all cases. Generally; values of the observed rate constants (k obs) were increasing with increasing of surfactant concentration in micellar media. AOT media was mainly more promotional than each of SDS and CTAB. A pseudo-phase kinetic model was applied and association constants of Ag + and OABA with surfactant micelles were calculated. Values of k obs for the reaction rates in microemulsion phases have been reported. AOT L2 microemulsion system has been found as the most promotional system among all the other studied systems. Association constants of Ag + and OABA with surfactant layer in microemulsion were calculated and tabulated. The reaction rate was increasing by increasing temperature in aqueous, micellar and microemulsion phases. The activation parameters H * , S * and G * have also been obtained. The reaction rate in different microemulsion media is affected by oil nature (n-heptane > n-hexane > npentane). Co-surfactants nature (n-butanol, n-pentanol and n-hexanol) has a very slight effect on k obs values in the case of CTAB or SDS microemulsion.