STUDY OF AQUEOUS ACIDIC PROPERTIES OF FULVIC-ACIDS BY EVOLVING FACTOR-ANALYSIS OF PH + FT-IR TITRATION DATA

被引:13
作者
MACHADO, AASC
DASILVA, JCGE
机构
[1] CIQ (UP), Chemistry Department, Faculdade de Ciências
关键词
D O I
10.1016/0169-7439(92)90052-H
中图分类号
TP [自动化技术、计算机技术];
学科分类号
0812 ;
摘要
A procedure for the estimation of the number and values of acidity constants from variations observed in aqueous Fourier transform infrared spectra of compounds containing carboxylic groups, including fulvic acids, with increasing pH, by using principal component analysis and evolving factor analysis, has been studied. The validation of the procedure was made by treating simulated data without and with random noise and data obtained in experiments with simple carboxylic compounds (acetic, shikimic, maleic, malonic and succinic acids) and binary mixtures of these compounds. The results for fulvic acids show two different types of carboxylic groups with pK(a) values of 2.8 and 4.6.
引用
收藏
页码:249 / 258
页数:10
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