CTAB Reverse Micelles as Catalysts for the Oxidation of Ascorbic Acid by K3[Fe(CN)6]

The oxidation of ascorbic acid by K3[Fe(CN)6] was studied in reverse micellar systems composed of CTAB (Cetyltrimethylammonium bromide), and it was found the observed first order (k1(aq) = 5.2×10−5 s−1, k1(rev) = 61.4×10−4 s−1) rate constant in reverse micellar medium is around forty times higher compared to aqueous medium under identical conditions. The rate enhancement (k2(aq) = 0.9×10−5 mole−1.dm3.sec−1, k2(rev) = 1.75×10−3 mole−1.dm3.sec−1) is attributed to the large concentration effect and lower dielectric constant in the reverse micelles. The rate of the reaction increases with increase in W = {[H2O]/[surfactant]} which is explained in terms of ionic strength of the water pool. The effect of surfactant concentration on rate was explained on the basis of Berezin pseudo phase model. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

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Kinetic Study of SN2 Reaction between Paranitrophenyl Benzoate and Hydrazine in the Presence of CTAB Reverse Micelles

BULLETIN OF CHEMICAL REACTION ENGINEERING AND CATALYSIS ◽

10.9767/bcrec.16.4.11036.744-751 ◽

2021 ◽

Vol 16 (4) ◽

pp. 744-751

Author(s):

K. Bhargavi ◽

P. Shyamala ◽

M. Padma ◽

K. V. Nagalakshmi

Keyword(s):

Open Access ◽

Kinetic Study ◽

Reverse Micelles ◽

Cetyltrimethylammonium Bromide ◽

Micellar Medium ◽

Water Pool ◽

First Order ◽

First Order Kinetics ◽

Open Access Article ◽

Reverse Micellar

Kinetic study of the reaction between p-Nitrophenyl benzoate (PNPB) by hydrazine (HYN) in the presence of Cetyltrimethylammonium bromide (CTAB)/Chloroform/Hexane reverse micellar medium shows that the reaction obeys first order kinetics with respect to each of the reactants. The rate of the reaction is much slower in reverse micellar medium compared to aqueous medium under identical conditions (kˈAq = 2.84×10−3 sec−1, krm =1.34×10−4 sec−1). The rate constants for the reaction in the reverse micellar medium have been determined at different values of W {W=[H2O]/[CTAB]} and at different concentrations of CTAB. It was found that the observed rate constant decreases with W. This kinetic behaviour was interpreted by using modified Berezin pseudo phase model, taking into consideration the distribution of the reactants, PNPB and hydrazine between the three pseudo phases, i.e., water pool, interface an organic phase. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

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Analysis of protein back-extraction processes in alcohol- and carboxylic acid-mediated AOT reverse micellar systems based on structural changes of proteins and reverse micelles

Biochemical Engineering Journal ◽

10.1016/j.bej.2004.08.004 ◽

2004 ◽

Vol 22 (1) ◽

pp. 71-79 ◽

Cited By ~ 16

Author(s):

Bong-Kuk Lee ◽

Dong-Pyo Hong ◽

Sung-Sik Lee ◽

Ryoichi Kuboi

Keyword(s):

Carboxylic Acid ◽

Reverse Micelles ◽

Structural Changes ◽

Back Extraction ◽

Micellar Systems ◽

Extraction Processes ◽

Reverse Micellar Systems ◽

Reverse Micellar

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Activity and Stability of Catalase in Nonionic Micellar and Reverse Micellar Systems

Zeitschrift für Naturforschung C ◽

10.1515/znc-2004-11-1220 ◽

2004 ◽

Vol 59 (11-12) ◽

pp. 887-891 ◽

Cited By ~ 12

Author(s):

Lidia Gebicka ◽

Monika Jurgas-Grudzinska

Keyword(s):

Aqueous Solution ◽

Reverse Micelles ◽

Micellar Solution ◽

Micellar Solutions ◽

Micellar Systems ◽

Brij 35 ◽

Aqueous Micellar Solution ◽

The Stability ◽

Reverse Micellar Systems ◽

Reverse Micellar

Catalase activity and stability in the presence of simple micelles of Brij 35 and entrapped in reverse micelles of Brij 30 have been studied. The enzyme retains full activity in aqueous micellar solution of Brij 35. Catalase exhibits “superactivity” in reverse micelles composed of 0.1 ᴍ Brij 30 in dodecane, n-heptane or isooctane, and significantly lowers the activity in decaline. The incorporation of catalase into Brij 30 reverse micelles enhances its stability at 50 °C. However, the stability of catalase incubated at 37 °C in micellar and reverse micellar solutions is lower than that in homogeneous aqueous solution.

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