Solid electrolyte - with catalytic electrode for gas analysis, e.g. for determn. of carbon mon:oxide and sulphur di:oxide in hot exhaust gases

摘要

Device for registering trace gases in an atmosphere, particularly of inorganic acid-anhydrides or carbon monoxide, has two surface mounted electrodes (2,3) on a solid-electrolyte (1) of sodium-beta-aluminate, with one electrode (2) possessing an electrically conductive catalyst, and the other electrode (3), which is located in the vicinity of the first electrode (2), being of material without catalytic activity with respect to the trace components being monitored in the atmosphere. The device is novel by virtue of the solid electrolyte having undergone an irreversible treatment by holding at 600 deg.C for 2h in an atmosphere contg. approximately 1% SO2. In a preferred (claimed) embodiment, a thin layer of solid electrolyte (1) is provided with two gold surface electrodes (2,3), with one electrode wire (2) being connected to a wire of catalytic material (13), e.g. of platinum. In use, the gas stream (A) under test is heated to approx. 600 deg.C and passed over the probe; the e.m.f. across the terminals (7,6) is measured. USE/ADVANTAGE - Monitoring probe for small amounts of e.g. SO2 and CO in exhaust gas, which provides high output signal amplitude, larger time constant, and improved reproducibility.