Kinetics and mechanism of oxidation of chondroitin-4-sulfate polysaccharide by chromic acid in aqueous perchlorate solutions

被引：11

作者：

Hassan, Refat ^{[1
]}

Ibrahim, Samia ^{[1
]}

Dahy, Abdel Rahman ^{[1
]}

Zaafarany, Ishaq ^{[2
]}

Tirkistani, Fand ^{[2
]}

Takagi, Hideo ^{[3
]}

机构：

[1] Assiut Univ, Fac Sci, Dept Chem, Assiut 71516, Egypt

[2] Umm Al Qura Univ, Fac Sci, Dept Chem, Makkah Al Mukarramah 13401, Saudi Arabia

[3] Nagoya Univ, Res Ctr Mat Sci, Dept Chem, Nagoya, Aichi 46401, Japan

来源：

CARBOHYDRATE POLYMERS | 2013年 / 92卷 / 02期

关键词：

Chondroitin-4-sulfate; Polysaccharides; Chromic acid; Catalysis; Oxidation; Kinetics; Mechanisms; Separation; POLY(VINYL ALCOHOL); PERMANGANATE ION; CHROMIUM(VI) OXIDATION; INTERMEDIATE COMPLEX; MACROMOLECULE; URANIUM(IV); MEDIA;

D O I：

10.1016/j.carbpol.2012.11.062

中图分类号：

O69 [应用化学];

学科分类号：

081704 ;

摘要：

The kinetics of chromic acid oxidation of chondroitin-4-sulfate polysaccharide as sulfated carbohydrates at a constant ionic strength of 4.0 mol dm(-3) has been investigated, spectrophotometrically. The reaction kinetics showed a first-order dependence in chromic acid and fractional-first-order kinetics with respect to the chondroitin-4-sulfate concentration. The influence of [H+] on the reaction rates showed that the oxidation process is acid-catalyzed. Added Mn2+ ions indicated the formation of Cr(IV) as intermediate species. A kinetic evidence for formation of 1:1 intermediate complex was revealed. The kinetic parameters have been evaluated and a tentative reaction mechanism in good consistent with the kinetic results obtained is discussed. (C) 2012 Elsevier Ltd. All rights reserved.

引用

页码：2321 / 2326

页数：6

共 34 条

[1] Kinetics and mechanism of permanganate oxidation of pectin polysaccharide in acid perchlorate media [J].