Development of a Simple Auto Exhaust Analyzer

摘要

A laboratory evaluation was completed regarding the feasibility of applying a heated filament, combustible gas detector to the separate measurement of total hydrocarbons and carbon monoxide in auto exhaust. Of the several candidate filament materials tested, only two--oxidized rhodium and wire-supported cobalt oxide--showed any potential for making the required analyses on the basis of temperature, and these both lacked the required stability to be useful. Two procedures for making a preliminary separation of the components were evaluated: selective oxidation of carbon monoxide over Hopcalite, and selective adsorption of hydrocarbons on silica gel. Neither of these was appropriate for incorporation in a simplified exhaust analyzer. The final experimental effort, a compromise on the original requirements, was an effort to construct a 'total combustibles' analyzer. This approach was unsuccessful because no way was found to selectively combust hydrogen in the presence of carbon monoxide. It was concluded from this research that the heated filament combustible gas detector has no promising application to auto exhaust analysis. (Author)