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Updated: Jun 28, 2026
12:06
Synthesis of High Purity Nonsymmetric Dialkylphosphinic Acid Extractants
Published on: October 19, 2017
The organic solvent effect on phosphomolybdic acid and its analytical application.
1Department of Chemistry, University of Kyoto, Kyoto, Japan.
Talanta
|September 1, 1971
Summary
A new spectrophotometric method quantifies phosphate ions using phosphomolybdic acid. Organic solvents alter ultraviolet spectra, enabling sensitive phosphate detection even at low molybdate concentrations.
Area of Science:
- Analytical Chemistry
- Inorganic Chemistry
Background:
- Phosphomolybdic acid exhibits distinct ultraviolet spectra.
- Organic solvents significantly influence these spectral properties.
Purpose of the Study:
- To develop a direct spectrophotometric method for phosphate ion determination.
- To leverage spectral changes for sensitive phosphate analysis.
Main Methods:
- Studying ultraviolet spectra of phosphomolybdic acid in aqueous and mixed solvents.
- Investigating the effect of organic solvents (e.g., tetrahydrofuran, ethanol) on spectral maxima.
- Optimizing conditions for quantitative phosphomolybdic acid formation at low molybdate concentrations and specific pH.
Main Results:
- Organic solvent addition caused a spectral shift with an absorption maximum at 310 nm.
- Quantitative formation of phosphomolybdic acid was achieved at approximately 10(-4)M molybdate and pH 3.
- A simple, direct spectrophotometric method for phosphate determination was successfully developed.
Conclusions:
- The spectral behavior of phosphomolybdic acid in mixed solvents provides a basis for phosphate analysis.
- The method is sensitive and effective for determining phosphate ions, even at low concentrations.
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