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Hydrogen peroxide generation R&D data obtained in an alkaline fuel cell-type electrochemical reactor with a dividing Nafion™ 117 membrane have been used to extract anion-conducting properties of the cation-exchange membrane. The effective diffusion coefficient of NaOH and the average transport number of OH − in the membrane were obtained by fitting a model formula for the total alkalinity of outlet catholyte to experimental alkalinities obtained with various electrolysis parameters’ values. The formula resulted from assumptions that NaOH diffuses through the membrane and OH − migrates through the membrane, and that HO 2 − does not penetrate the membrane. The membrane parameters extracted in this way were in good agreement with similar data reported by others for Nafion™. Hydrogen peroxide current efficiencies remained over 90% and H 2 O 2 concentrations reached 7 wt.%, however the fuel cell reactor's electrical efficiency was strongly limited by high internal resistance.

Two limiting-case simplified models of mass- and charge-transport phenomena in a flow-through electrochemical reactor were developed. It is postulated that the true experimental system's behavior falls in between. The models account for energy loss due to the ohmic drop, forced convection, diffusion, and migration. The calculation results were compared against experimental data.

The effect of tensioactive agents (TSA = SDS, BRIJ35, BRIJ78, BRIJ99, and CTAB) on the kinetics of hydrogen evolution at a rotating nickel electrode in 0.2 M solutions of Na2SO4 was investigated. It was found that at higher concentrations of TSA, their presence inhibited the reaction although their adsorption behaviour at the nickel electrode is different. We concluded that BRIJ35 and CTAB should show better performance in the hydrogenation of organic compounds than SDS.

The Kamlet and Taft basicity parameters βKT, for twelve mixtures of organic solvents with water are reported. Also the data for water-butanols (n-BuOH. i-BuOH. and s-BuOH) and alcohols (MeOH, EtOH. n-PrOH. and i-PrOH)-n-hexane mixtures are given. It was found that in the case of mixtures of 1.4-dioxane. acetone, tetrahydrofuran. dimethylsulfoxide. and acetonitrile with water, the basicity parameters of the mixture are higher than that of pure solvents in a region of smaller concentrations of water. These results, together with earlier reported results for THF and Et2O mixtures with MeOH are discussed in terms of breaking off the structure of the more structurized solvent (water and MeOH). All these mixtures, except the W-THF mixture, show the excess thermodynamic func­tions (ΔHE and ΔSh) analogous to MeOH-CCl4 mixtures, where depolymerization of MeOH clusters was postulated. Relativity of different basicity scales in respect to the acidic probe molecule is also shortly discussed