Acids extraction by amine-based extractants: An analysis of the effect of anion concentration in the aqueous phase using the Donnan model

被引:5
作者
Canari, R [1 ]
Eyal, AM [1 ]
机构
[1] Hebrew Univ Jerusalem, Casali Inst Appl Chem, IL-91904 Jerusalem, Israel
关键词
D O I
10.1021/ie010581g
中图分类号
TQ [化学工业];
学科分类号
0817 ;
摘要
The concentration of an acid's anion in the aqueous phase affects that acid's extraction efficiency by amine-based extractants. The anion effect is explained by using the acid-dissociation equation in the case that the acid is mainly extracted though H-bonding or solvation. This explanation does not hold in the extraction of strong acids such as hydrochloric or dichloroacetic acid by a relatively strong base extractant (pK(aB) much greater than pK(aA)). To explain the anion effect in these systems, we reexamined our theory and modified it with the Gibbs-Donnan model. The modified theory shows that the proton activity in the organic phase could differ significantly from that in the aqueous phase, depending on the relative activities of the anions in those two phases. Thus, in turn, the relative activity of the anion affects the protonation of the amine in the organic phase, pK(aB). Accordingly, the modified theory successfully explains the effect of the anion concentration on the extraction efficiency.
引用
收藏
页码:1315 / 1320
页数:6
相关论文
共 35 条
[1]  
Amrane A, 1999, J CHEM TECHNOL BIOT, V74, P33, DOI 10.1002/(SICI)1097-4660(199901)74:1&lt
[2]  
33::AID-JCTB994&gt
[3]  
3.0.CO
[4]  
2-K
[5]  
BANIEL AM, 1973, Patent No. 1426018
[6]   AMINE EXTRACTION OF CITRIC-ACID - EFFECT OF DILUENT [J].
BIZEK, V ;
HORACEK, J ;
KOUSOVA, M .
CHEMICAL ENGINEERING SCIENCE, 1993, 48 (08) :1447-1457
[7]  
Bolto B.A., 1977, ION EXCHANGE SOLVENT, V7, P221
[8]   Selectivity in monocarboxylic acids extraction from their mixture solutions using an amine-based extractant: Effect of pH [J].
Canari, R ;
Eyal, AM .
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH, 2003, 42 (07) :1301-1307
[9]   Extraction of carboxylic acids by amine-based extractants: Apparent extractant basicity according to the pH of half-neutralization [J].
Canari, R ;
Eyal, AM .
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH, 2003, 42 (07) :1285-1292
[10]   Effect of pH on dicarboxylic acids extraction by amine-based extractants [J].
Canari, R ;
Eyal, AM .
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH, 2003, 42 (07) :1293-1300