Skip to content
Research Article Open access CC BY 3.0

Kinetics of Oxidation of Substituted Phenols by Potassium Bromate

Asha Mathew, Jaya Kishore Panda

International Research Journal of Pure and Applied Chemistry · pp. 196–210 · Published 16 Oct 2012

10.9734/IRJPAC/2012/1242

Abstract

Kinetic methods of analysis are now accepted as standard analytical procedures for several of reactions, especially oxidation types. Though the reaction of phenols and substituted phenols by potassium bromate is well understood as an oxidative type, there was a need to understand and more evidence required against the participation of Br2 in the increasing rate of reaction with increasing acetic acid composition in the bromate oxidation of phenols. Present work explains the strange behaviour on the basis of formation of HBrO3 that is favoured in acidic medium. Kinetics of oxidation of 3, 4-Dimethyl phenol, 4-sec-butyl phenol and 4-tert-butyl phenol in aqueous acetic acid - water medium in the temperature range of 308K to 321K were investigated. The reaction obeys first order kinetics with respect to [oxidant], [substrate] and [H+]. The active oxidising species was found to be HBrO3. A suitable mechanism in conformity with the kinetic observation has been proposed. Various activation parameters such as energy of activation (58.59, 61, 43, 65.38 KJ/mol), enthalpy change [56.03, 58.87, 62.82 KJ/mol], free energy change (73.19, 77.17, 77.82 KJ/mol) and entropy of activation (-55.7, -59.45 and -48.78 J/mol/deg) for 3: 4-dimethyl phenol, 4-sec-butyl phenol, 4-tert-butyl phenol at 308K, were obtained. A rate law has been derived on the basis of the data. The order of reactivity among the methyl substituted phenols is 3, 4-dimethyl phenol > p-cresol > phenol. The order of reactivity among higher alkyl substituted phenols is 4-tert-butyl phenol 4-sec-butyl phenol > 4-ethyl phenol >phenol.  

3, 4-dimethyl phenol 4-sec-butyl phenol 4-tert-butyl phenol potassium bromate oxidation kinetics

References (13)

  1. 1 The Oxidation of Ethyl Alcohol in the Presence of Bromate and Bromine [DOI]
  2. 2 CXXXVII.—The purification of acetic acid. The estimation of acetic anhydride in acetic acid [DOI]
  3. 3 Kinetics and mechanism of oxidation of secondary alcohols by potassium bromate [DOI]
  4. 4 The kinetics of oxidation of secodary alcohols by potassium bromate [DOI]
  5. 5 Kinetics and mechanism of ruthenium tetroxide catalysed oxidation of cyclic alcohols by bromate in a base [DOI]
  6. 6 Kinetics and mechanism of rhodium(III)-catalysed oxidation of 1,2-glycols by acid bromate [DOI]
  7. 7 Ru (III) Catalyzed Oxidation of Aliphatic Ketones by N-Bromosuccinimide in Aqueous Acetic Acid: A Kinetic Study [DOI]
  8. 8 Mechanism of ruthenium tetroxide-catalysed oxidation of aldoses by alkalineN-bromoacetamide [DOI]
  9. 9 A kinetic study of the oxidation of α‐hydroxy acids and α‐hydroxy ketones by potassium bromate [DOI]
  10. 10 Kinetics and mechanism of the oxidation of alcohols by N-bromoacetamide in alkaline solution [DOI]
  11. 11 Mechanism of Ru(III) catalysis in acid bromate oxidation of 2-methylcyclohexanol [DOI]
  12. 12 Ruthenium(III) Catalyzed Oxidation Of Ethylenediaminetetraacetic Acid By N-Bromosuccinimide In Aqueous Alkaline Medium – A Kinetic And Mechanistic Study [DOI]
  13. 13 A text-book of quantitative inorganic analysis [DOI]

Cited by 6

Reduction Kinetics of 3,7-bis (dimethylamino)-4-nitro-phenothiazine-5-ium Chloride (Methyelene Green) with Potassium Persufate in Presence of Halides

Rehana Saeed, Fahim Uddin, Maria Ashfaq, Muna Irfan, Zahida Khalid · International Research Journal of Pure and Applied Chemistry · 2013

Determination of 55Fe in urine by liquid scintillation counting

Nicolas Guérin, Xiongxin Dai · Journal of Radioanalytical and Nuclear Chemistry · 2015

Mechanistic and thermodynamic aspects of oxidative removal of flucloxacillin by different oxidants in an acidic medium

A. Fawzy, M. Abdallah, N. Alqarni · Journal of Molecular Liquids · 2021

Showing 3 of 6 known citations — external sources report more than can currently be individually listed.

Related research

Article metrics

Real usage data collected on this platform.

42

Page views

0

PDF downloads

23

Outbound clicks

6

Citations

Views over time

Views by country

Approximate, from request IP at view time — not citizenship or institution. Countries with fewer than 5 views are grouped as "Other".

Traffic sources

Referring site, by host.

Views and downloads exclude known bots/crawlers. Citations combines this platform's own DOI-resolved index with each external source's own reported total — see Cited by above for individually listed citing works. Last refreshed 0 seconds ago.