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三辛胺萃取丁二酸、苹果酸、马来酸、富马酸特性的研究

李振宇; 秦炜; 汪敏; 黄焱; 戴猷元   

  1. Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
  • 收稿日期:1900-01-01 修回日期:1900-01-01 出版日期:2002-06-28 发布日期:2002-06-28
  • 通讯作者: 李振宇

Equilibrium of Extraction of Succinic, Malic, Maleic and Fumaric Acids with Trioctylamine

LI Zhenyu; QIN Wei; WANG Min; HUANG Yan; DAI Youyuan   

  1. Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
  • Received:1900-01-01 Revised:1900-01-01 Online:2002-06-28 Published:2002-06-28
  • Contact: LI Zhenyu

摘要: Extraction equilibrium features of succinic acid, malic acid, maleic acid and fumaric acid
were investigated systematically with trioctylamine (TOA) in chloroform, 4-methyl-2-
pentanone (MIBK) and 1-octanol. Fourier transform-infrared (FTIR) spectroscopic analysis of
organic samples loaded with the acid shows that amine forms 1:1 complex of ion-pair
association with succinic acid, malic acid and maleic acid, and 1:1, 2:1 complex of ion-
pair association with fumaric acid. It is proposed that the complex forms depend on the
second dissociation constant of the dibasic acid, pKa2. Results of equilibrium experiments
show that diluents affect extraction behavior, and depend on the solute concentration.
Protic diluents, chloroform and 1-octanol, are more effective than the others when the
equilibrium solute concentration is lower than 1:1 stoichiometry of TOA to acid, otherwise
the extraction ability shows that MIBK>l-octanol>chloroform for malic and maleic acids,
and 1-octanol>MIBK>chloroform for succinic acid. Overloading (solute concentration in
organic phase is lager than TOA concentration) appears for all of the studied acids, and
the sequence of overloading amount is the same as that of distribution constant of diluent.
The results show that the sequence of extraction ability of different acid is the same as
that of acidity at low equilibrium solute concentrations, while it is the same as the
sequence of hydrophobicity at high equilibrium concentrations.

关键词: succinic acid;malic acid;maleic acid;fumaric acid;ion-pair association;extraction behavior

Abstract: Extraction equilibrium features of succinic acid, malic acid, maleic acid and fumaric acid
were investigated systematically with trioctylamine (TOA) in chloroform, 4-methyl-2-
pentanone (MIBK) and 1-octanol. Fourier transform-infrared (FTIR) spectroscopic analysis of
organic samples loaded with the acid shows that amine forms 1:1 complex of ion-pair
association with succinic acid, malic acid and maleic acid, and 1:1, 2:1 complex of ion-
pair association with fumaric acid. It is proposed that the complex forms depend on the
second dissociation constant of the dibasic acid, pKa2. Results of equilibrium experiments
show that diluents affect extraction behavior, and depend on the solute concentration.
Protic diluents, chloroform and 1-octanol, are more effective than the others when the
equilibrium solute concentration is lower than 1:1 stoichiometry of TOA to acid, otherwise
the extraction ability shows that MIBK>l-octanol>chloroform for malic and maleic acids,
and 1-octanol>MIBK>chloroform for succinic acid. Overloading (solute concentration in
organic phase is lager than TOA concentration) appears for all of the studied acids, and
the sequence of overloading amount is the same as that of distribution constant of diluent.
The results show that the sequence of extraction ability of different acid is the same as
that of acidity at low equilibrium solute concentrations, while it is the same as the
sequence of hydrophobicity at high equilibrium concentrations.

Key words: succinic acid, malic acid, maleic acid, fumaric acid, ion-pair association, extraction behavior