Method and Device for Detecting Odorants in Hydrocarbon Gases

摘要

A dual quartz crystal microbalance (QCM) sensor is disclosed for use in a hand-held detection device (10) for detecting the presence of an odorant in hydrocarbon gaseous fuels. The odorant is a thiol-based compound, such as ethanethiol. One QCM (16) is coated with a coating typically containing a reagent that specifically reacts with the thiol of the odorant and alters its oscillation frequency as a result of mass gained in the reaction. A second QCM (16′) serves as a control and the two frequency signals may be heterodyned (26) to produce a delta-frequency representative of the mass change. Circuitry and signal processing (32) are used to produce a final result correlated to the level of thiol in the hydrocarbon gas.

主权项

1. A portable device for detecting thiol odorants in a hydrocarbon gas, the device comprising in a housing:
a power source for producing a current; a thiol sensor comprising
a piezo-crystalline substrate disposed in the housing and located for fluid communication with the hydrocarbon gas,a coating on the piezo-crystalline substrate, the coating capable of reacting specifically with and capturing thiol components from a gaseous phase, while substantially not reacting with the hydrocarbon gas itself; an oscillator circuit, the thiol sensor forming a part of the oscillator circuit, whereby, upon receiving a current input from the power source, the piezo-crystalline substrate oscillates at a first frequency prior being exposed to thiol odorants in a gas, and at a second frequency after being exposed to thiol odorants in the gas and capturing thiols in the coating, the second frequency differing from the first frequency in proportion to the amount of thiol captured.