摘要
介绍了研究木质素磺酸(LS)分子结构特性值的常用方法。系统地研究了络合、氧化反应对 LS分子结构的影响。分析了络合、氧化反应的作用机理。
The molecular structures of oxidation products and metal (Fe^(2+) and Cr^(3+)) complexes of lignosulfonic acid (LSA)are studied UV and IR spectrometry and by means of measuring their characteristic viscosity [η] in 1% NaCl solution.The oxidation of LSA is conducted in aqueous solutions by various oxidants:ammonium,persulfate,hydrogen peroxide,nitric acid,and sodium bichromate.The oxidation in concentrated (33%) solutions leads to increasing [η],or molecular weight,what indicates that the polymerization processes are dominant,the oxidation in dilute solutions by a large amount of oxidants-to decreasing [η] and consequently to degrading LSA molecules.In oxidation processesa decrease of phenolic hydroxyl groups(determined from differential UV spectrum data) in LSA molecules is observed.The degration of LSA molecules in oxidation processes is accompanied by the formation of carbonyl groups conjugated with aromatic radicals.For Fe^(2+) and Cr^(3+)/LSA complexes,no obvious changes in [η] value and phenolic hydroxyl content are observed and their UV and IR spectra remain prac- tically unchanged as compared to original LSA.
出处
《油田化学》
CAS
CSCD
北大核心
1992年第2期104-109,共6页
Oilfield Chemistry
关键词
木质素磺酸
氧化反应
分子结构
Lignosulfonic Acids
Oxidation
Complexation
Polyvalent Metal Ions
Modified Lignins
Molecular Structures
