On-Line Chemical Sensors For Use In Agressive Process Streams

79 On-Line Chemical Sensors For Use In Aggressive Process Streams--T/J Technologies, Inc., P.O. Box 2150, 3850 Research Park Drive, Ste. A, Ann Arbor, MI 48106-2150; (313) 213-1637 Dr. Pei-Lin Chen, Principal Investigator Mr. Leslie H. Alexander, Business Official DOE Grant No. DE-FG02-97ER82495 Amount: $75,000 There is a growing need for compact on-line chemical sensors for the analysis and/or detection of gases under a broad range of operating conditions in many energy production, industrial and agricultural applications. Transducer materials that are highly sensitive and can be operated under the harsh conditions typical of furnaces, boilers, distillation columns and food processing are especially desirable. Early transition metal carbides and nitrides hold great promise for use in chemical sensors. They are thermally stable at elevated temperatures, are chemically stable upon exposure to corrosive gases, adsorb a variety of gases, and have high electronic conductivities. Furthermore, they can be made in the form of high surface area films. During the Phase I effort, the feasibility of using vanadium carbide and nitride based transducers for the selective detection of saturated, unsaturated and/or oxygenated hydrocarbons will be demonstrated. Changes in the transducer electrical resistivity caused by exposure to these analytes will be used to assess the sensitivity and selectivity. Responses to thermal treatments during exposure to the analytes will establish the thermal and chemical stability limits. Phase II will optimize the performance of the vanadium carbides and nitrides and extend the approach by developing microsensor arrays based on a variety of related materials. Commercial Applications and Other Benefits as described by the awardee: This project would lead to the new class of transducer materials for quantitative on-line analysis of multicomponent streams under harsh conditions. Process control and continuous emissions monitoring represent two broad areas of potential commercial application. In particular, it is expected that sensors capable of detecting hydrocarbons, NO, CO, SO2 and halogens would be beneficial in improving the energy efficiency and reducing emissions from fossil fuel combustion and chemical processing facilities._