Quantitative detection of potassium chloride solutions at different concentrations using terahertz waves

Area of Science:

• Spectroscopy
• Terahertz Technology
• Analytical Chemistry

Background:

• Terahertz (THz) detection uses electromagnetic waves for material analysis, interacting with molecular vibrations.
• Water's high absorption in the THz range presents challenges for THz time-domain spectroscopy (THz-TDS) in aqueous samples.
• Existing methods for potassium chloride detection do not utilize THz-TDS, especially in solution.

Purpose of the Study:

• To investigate the terahertz spectral properties of potassium chloride (KCl) in powdered form and aqueous solutions.
• To evaluate the feasibility of using THz-TDS for quantifying potassium chloride concentrations in solutions.
• To address the unexplored application of THz-TDS for analyzing potassium chloride in aqueous environments.

Main Methods:

• Terahertz time-domain spectroscopy (THz-TDS) was employed.
• The study analyzed powdered potassium chloride and aqueous solutions ranging from 3 to 60 mmol/L.
• Spectral behavior and absorption characteristics were measured across the terahertz range.

Main Results:

• Potassium chloride solutions exhibited a distinct absorption peak in the terahertz spectrum.
• The intensity of this absorption peak decreased proportionally with increasing potassium chloride concentration.
• The study successfully characterized the THz spectral response of KCl in aqueous solutions.

Conclusions:

• THz-TDS is a viable technique for the rapid and non-invasive quantification of potassium chloride in solutions.
• The observed concentration-dependent absorption peak provides a reliable basis for quantification.
• This research establishes THz-TDS as a precise, safe, and efficient analytical tool for potassium chloride solutions.