A Concept of a Sensor System for Determining Composition of Organic Solvents

This paper presents the results of work on a gas sensor system for determining qualitative and quantitative composition of organic solvents. The system performs the analysis of gaseous mixtures, which are obtained by evaporating liquid solvents and therefore directly represent their composition. The system utilizes gas sensor array, which is built of Taguchi gas sensors (TGS). It provides patterns of measured solvents which are analyzed by pattern recognition module. The module employs multivariate statistical tools like discriminant function analysis (DFA) and partial least squares (PLS) regression. The determination of solvent composition is organized in a hierarchical structure. The concept of the system was experimentally verified using the example of two-component solvents. It was here demonstrated that the proposed system is capable of determining qualitative and quantitative composition of liquid solvents.