SILVER CORROSION AND SULFUR DETECTION USING A QUARTZ-CRYSTAL MICROBALANCE WITH SILVER ELECTRODE SURFACES

A quartz crystal microbalance (QCM) with silver electrodes is used for detection of sulfur and measurement of silver corrosion by sulfur in jet fuels. It is found that the device responds very sensitively to el emental sulfur by reaction at the silver surface, resulting in the for mation of surface silver sulfide. It is also expected that the device will respond to hydrogen sulfide. The response of the QCM is found to depend on the fuel matrix, The presence of oxygen inhibits the surface reaction, resulting in a lower mass accumulation. It is also found th at the sulfur compounds which produce a response in this test are not players in the formation of autoxidative surface deposition. It is sho wn that the QCM response (surface mass per unit time) is proportional to the concentration of elemental sulfur present in the fuel.