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Updated: Jul 11, 2026
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Synthesis of High Purity Nonsymmetric Dialkylphosphinic Acid Extractants
Published on: October 19, 2017
An ATR-FTIR study of different phosphonic acids in aqueous solution
María C Zenobi1, Carina V Luengo, Marcelo J Avena
1Departamento de Química, Universidad Nacional del Sur, Avda. Alem 1253, (B8000CPB) Bahía Blanca, Argentina. mzenobi@criba.edu.ar
Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
|September 11, 2007
Summary
This study used ATR-FIR spectroscopy to analyze phosphonic acids (HEDP, NTMP, BHAMP) in water. Changes in vibrational spectra with pH reveal protonation steps and the stable zwitterionic nature of BHAMP and NTMP.
Area of Science:
- Analytical Chemistry
- Physical Chemistry
- Spectroscopy
Background:
- Phosphonates are widely used in various industrial applications.
- Understanding their behavior in aqueous solutions is crucial for optimizing their use.
- Vibrational spectroscopy provides insights into molecular structure and interactions.
Purpose of the Study:
- To investigate the vibrational spectra of HEDP, NTMP, and BHAMP in aqueous solutions.
- To determine the effect of pH on the spectral properties of these phosphonates.
- To assign specific vibrational bands and understand their structural implications.
Main Methods:
- Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FIR) spectroscopy was employed.
- Measurements were conducted across a pH range of 5 to 9.
- Mid-infrared region (900-1200 cm(-1)) was the primary focus for analysis.
Main Results:
- Key vibrational bands, including nu(POH) at ~925 cm(-1) and nu(PO(3)(2-)) at ~970 cm(-1), showed significant pH-dependent changes.
- Evidence for the zwitterionic nature of BHAMP and NTMP was observed.
- The zwitterionic form remained stable across the studied pH range.
Conclusions:
- The study successfully characterized the vibrational spectra of HEDP, NTMP, and BHAMP.
- ATR-FIR spectroscopy effectively demonstrated pH-induced protonation steps in these phosphonates.
- The findings confirm the stability of the zwitterionic forms of BHAMP and NTMP in aqueous solutions.
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