Determination of trace amounts of hydrogen sulfide in a gas flow using a piezoelectric detector

The following parameters are substantiated and optimized in the detection of H2S in a gas flow: the nature and flow rate of the carrier gas; the qualitative and quantitative composition of a sensing coating; the technique of its application onto the electrodes of a piezoelectric detector; and the geometrical parameters (volume and configuration) of a flow detecting cell. A testing unit for detecting H2S in the range from 3 to 18 mg/m(3) is developed on the basis of a modified piezoelectric resonator with high frequency characteristics (13-16 MHz).