Chromatographic Detector Based on Adsorption-Semiconductor Sensor for Detection of Reducing Gases in Air

A semiconductor sensor with a gas sensitive layer based on SnO2 and Sb2O5 with Pd additive synthesized by co-precipitation was studied as a chromatographic detector. It was found that the subject detector, using air as a carrier gas, can selectively detect each of the reducing gases (H2, CO, CH4, C2H2, C2H4, C2H6) which can leak into transformer oil if defects emerge during high-voltage transformers operation. It was established that for the fabricated detector the dependences of the signals on concentrations of the analyzed gases are linear in the range of 0–50 ppm for H2, CO, CH4 and 0–100 ppm for C2H2, C2H4, C2H6. The detector can be on-stream as combined with a chromatograph instrumentality which is rational for a wide practical application. The usage of the semiconductor detector based on the adsorption-semiconductor sensor is promising to significantly reduce the detection cost of the gases and to simplify diagnostics of the high-voltage transformer conditions.