P. Sar, Aniruddha Ghosh, Susanta Malik
Oct 25, 2016
Citations
0
Influential Citations
35
Citations
Journal
Journal of Industrial and Engineering Chemistry
Abstract
Abstract Oxidation of the three isomeric pentanols by potassium dichromate in aqueous acidic medium was investigated spectrophotometrically at 25 °C. The oxidation leads to the formation of corresponding carbonyl products as identified by 1 H NMR measurement and other techniques. The effects of cationic (cetylpyridinium chloride, CPCl), anionic (sodium dodecylsulphate, NaDS) and nonionic surfactant (polyoxyethylene octyl phenyl ether, TX-100) on reaction kinetics were studied. Moreover the catalytic effect of surfactant in presence of three heteroaromatic nitrogen bases: 2-picolinic acid (2-PA), 2,2′-bipyridyl (2,2′-bipy) and 1,10-phenanthroline (1,10-phen) on the oxidation were also investigated. The value of the rate constant in promoted and unpromoted reaction has been found to be higher in NaDS than in TX-100 and CPCl micellar medium. Conductivity and tensiometry measurements were carried out to determine critical micellization concentration and free energy of micellization (Δ G m °) of the used surfactant in presence of three pentanols. Among the different surfactant and promoter the combination of 2,2′-bipy and NaDS is efficient to exhibit ∼1000 fold rate enhancement for oxidation of 1-pentanol and it is ‘selective’ over the rest of two pentanols oxidation.