Development of a Novel Thermal Technique for Detection of Water in Solvents

Author(s): Joe Kirkup, Prab Birdi, Phil Radford, Kam Chana

Accurate measurement of water concentration in various common solvents presents significant challenges due to the limitations of traditional detection methods, including low throughput and high costs. This study introduces a novel thermal detection technique, the LiquiSensor probe, designed for low-cost, rapid, and accurate quantification of water concentration in ethanol. The measurement principle utilizes differential thermal responses across a range of water concentrations (0-30%) in ethanol, combined with a reverse interval partial least squares (iPLS) regression model. In blind benchtop trials, LiquiSensor demonstrated accuracy within <1% of the actual water concentrations, with a standard deviation of 0.107%, indicating excellent precision, and a measurement time of only 10 minutes for multiple readings (with potential for reduction). This rapid response time, coupled with high accuracy and precision, presents significant opportunities for in-situ process monitoring as well as benchtop quality control.