Separation of compounds with multiple -OH groups from dilute aqueous solutions via complexation with organoboronate. [1,2-propanediol]
The complexing extractant agent investigated in this work is 3-nitrophenylboronic acid (NPBA) in its anionic form (NPB). NPBA and Aliquat 336 (quaternary amine) is dissolved in 2-ethyl-l-hexanol, and the extractant is contacted with aq. NaOH. Solutes investigated were 1,2-propanediol, glycerol, fructose, sorbitol and lactic acid. Batch extraction experiments were performed at 25{degree}C. Partition coefficients, distribution ratios and loadings are reported for varying concentrations of solute and NPB. All solutes complexed with NPB{sup {minus}}, with all complexes containing only one NPB{sup {minus}} per complex. The 1:1 complexation constants for the solutes glycerol, fructose and sorbitol follow trends similar to complexation with B(OH){sub 4}{sup {minus}} (aq.), i.e. the complexation constants increase with increasing number of {minus}OH groups available for complexation. Assumption of 1:1 complex is not valid for 1, 2-propanediol, which showed overloading (more than one mole of solute complexed to one mole NPB{sup {minus}}) at higher concentrations. The {minus}OH group on the NPB{sup {minus}} which is left uncomplexed after one solute molecule had bound to the other two {minus}OH groups may be responsible for the overloading. Overloading is also observed in extraction of tactic acid, but through a different mechanism. It was found that TOMA{sup +} can extract lactic acid to an extent comparable to the uptake of lactic acid by NPB{sup {minus}}. The complexation is probably through formation of an acid-base ion pair. Losses of NPBA into the aqueous phase could lead to problems, poor economics in industrial separation processes. One way of overcoming this problem would be to incorporate the NPBA onto a solid support.
- Research Organization:
- Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
- Sponsoring Organization:
- USDOE; USDOE, Washington, DC (United States)
- DOE Contract Number:
- AC03-76SF00098
- OSTI ID:
- 7047671
- Report Number(s):
- LBL-32430; ON: DE92041201
- Resource Relation:
- Other Information: Thesis (M.S.)
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
FRUCTOSE
SEPARATION PROCESSES
GLYCEROL
GLYCOLS
LACTIC ACID
SORBITOL
AQUEOUS SOLUTIONS
CHEMICAL REACTION KINETICS
COMPLEXES
DILUTION
ORGANIC BORON COMPOUNDS
ALCOHOLS
BORON COMPOUNDS
CARBOHYDRATES
CARBOXYLIC ACIDS
DISPERSIONS
DIURETICS
DRUGS
HEXOSES
HYDROXY ACIDS
HYDROXY COMPOUNDS
KETONES
KINETICS
MIXTURES
MONOSACCHARIDES
ORGANIC ACIDS
ORGANIC COMPOUNDS
REACTION KINETICS
SACCHARIDES
SOLUTIONS
400105* - Separation Procedures