On the influence of the solvent and the temperature on the speed of oxidation of some organic substances by chromic acid. II

Snethlage, H. C. S.

doi:10.1002/recl.19400590204

Cited by 7 publications

(1 citation statement)

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

“…There are several reports available in the literature on the oxidation of dicarboxylic acids by metal oxidants such as Vanadium (V), Chromium (VI) [20][21][22][23][24][25] and tetrachloroaurate (III) ion. [26] However, the details of micellar effect on oxidation of oxalic acid by N-bromophthalimide are yet unknown.…”

Section: Introductionmentioning

confidence: 99%

Catalytic Effect of Cetyltrimethylammonium Bromide on the Oxidation of Oxalic Acid by N-Bromophthalimide in Acidic Medium

Katre

Mudliar

Joshi

et al. 2012

Journal of Dispersion Science and Technology

View full text Add to dashboard Cite

The kinetics of micellar catalyzed oxidation of oxalic acid [OA] by N-bromophthalimide was studied in the presence of perchloric acid at 308 K. The orders of reaction with respect to [Oxalic acid], [oxidant], and [H þ ] were found to be fractional, first and negative fractional order respectively. Cationic micelles of cetyltrimethylammonium bromide increased the reaction rate. The effect of phthalimide, mercuric acetate and inorganic salts, that is, [Cl À ][Br À ] has also been done. The rate reaction decreases with increasing dielectric constant of the medium. The results are treated quantitatively in terms of Piszkiewicz and Berezin models. The rate constant (K obs ), cooperatively index (n), binding constant (k s þ k o ), and corresponding activation parameters (E a , DH # , DS # , and DG # ) were determined. A suitable mechanism consistent with the experimental finding has been proposed.

show abstract

Section: Introductionmentioning

confidence: 99%

Catalytic Effect of Cetyltrimethylammonium Bromide on the Oxidation of Oxalic Acid by N-Bromophthalimide in Acidic Medium

Katre

Mudliar

Joshi

et al. 2012

Journal of Dispersion Science and Technology

View full text Add to dashboard Cite

show abstract

Determination of calorific value of feedstuffs by chromic acid oxidation

O’Shea¹,

Maguire²

1962

J Sci Food Agric

View full text Add to dashboard Cite

X method is described for the determination of the calorific value of feedstuffs by oxidation with a solution of potassium dichromate in sulphuric acid. Energy values are obtained by dividing the amount of 1.jN-dichromate used t o oxidise I g. of material by a factor dependent on the protein content. The technique is simple, rapid, applicable to large numbers of samples and gives results in good agreement with those obtained by bomb calorimetry. IntroductionThe determination of the gross energy of feeds and faeces is a technique frequently employed in nutritional investigations. Conventional methods of bomb calorimetry give results with a high degree of accuracy but are limited in the number of assays that can be carried out in a given time, Raymond et a1.l have described the use of an adiabatic bomb calorimeter which considerably increases the speed of assay. More recently Miller & Payne2 developed a ballistic bomb calorimeter with which more rapid but somewhat less accurate determinations can be carried out. The present investigation describes the determination of gross energy by a wet oxidation technique.There are many references in the literature to the oxidation of organic compounds with chromic acid and the mechanism of a number of these reactions has been intensively ~tudied.3-~ Walkley & Black6 used this oxidant in their procedure for the estimation of organic matter in soil. The variable nature of the soil organic matter as well as high concentrations of inorganic chloride were found to lead to errors in results. Rozental' has oxidised a wide variety of substances with chromic acid. In general, carbohydrates and fats were found to be almost quantitatively oxidised to carbon dioxide and water, as also were a number of organic acids, with the exception of acetic acid. Proteins in most cases were not quantitatively oxidised, urea and alanine were completely unaffected. From his results Rozental derived coefficients relating the energy content of compounds to the amount of dichromate necessary for their oxidation.

show abstract

On the influence of solvent and temperature on the speed of oxidation of some organic substances by chromic acid. III

Snethlage¹

1941

Recl. Trav. Chim. Pays‐Bas

View full text Add to dashboard Cite

The velocity of the reaction between succinic acid and chromic acid has been measured in mixtures of sulphuric acid and water containing from 62.50 to 95.36:/, sulph. ac. a t temperatures between 313" and 413" K. In these solvents the velocity is nearly proportional to the concentration of both reagents. The temperature coefficient of this velocity decreases with increasing temperature, the rate of this decrease being characteristic for each solvent. In this respect the solvents may be divided into two groups, the limit between the two lying a t 70 % sulph. ac. E - RTThe "constants" A and E in A r r h e n i u s ' formula k = A . e are in this case dependent on the temperature. T h e variation of these values with the composition of the solvent leads to the conclusion that the velocity of the oxidation in solvents containing mote than 70 % sulph. ac. is determined by the presence of the hydrate so3 3 aq.. while in more dilute solutions the hydrate so3 5 aq. may play a corresponding r d e .

show abstract

On the influence of the solvent and the temperature on the speed of oxidation of some organic substances by chromic acid. II

Cited by 7 publications

References 1 publication

Catalytic Effect of Cetyltrimethylammonium Bromide on the Oxidation of Oxalic Acid by N-Bromophthalimide in Acidic Medium

Catalytic Effect of Cetyltrimethylammonium Bromide on the Oxidation of Oxalic Acid by N-Bromophthalimide in Acidic Medium

Determination of calorific value of feedstuffs by chromic acid oxidation

On the influence of solvent and temperature on the speed of oxidation of some organic substances by chromic acid. III

Contact Info

Product

Resources

About