A NEW ATMOSPHERIC AMMONIA DETECTOR BASED ON SUPERCONDUCTOR METAL OXIDES OR MOO3 ANNULAR DENUDER TUBES

THIS PHASE I PROJECT INVOLVES THE DEVELOPMENT OF A RAPID RESPONSE ATMOSPHERIC MONITOR FOR TRACE LEVELS OF GAS-PHASE AMMONIA. THE DETECTOR IS BASED ON THE USE OF A METAL OXIDE ANNULAR DENUDER TUBE FOR THE COLLECTION OF GASEOUS AMMONIA. WHEN HEATED, THIS TUBE CONVERTS AMMONIA TO NITRIC OXIDE WHICH IS THEN DETECTED BY A CHEMILUMINESCENT REACTION WITH OZONE. TWO METAL OXIDE CATALYSTS WILL BE EVALUATED FOR THE SORPTION AND CONVERSION OF NH3 TO NO, MOLYBDENUM (VI) OXIDE COATING ON MOLYBDENUM METAL RODS AND DENUDER TUBES PREPARED USING RARE EARTH/BARIUM/COPPER OXIDES OF THE COMPOSITION RECENTLY SHOWN TO EXHIBIT HIGH TEMPERATURE SUPERCONDUCTING PROPERTIES. THE AMMONIA DETECTOR, USING EITHER MATERIAL IN AN ANNULAR DENUDER TUBE DESIGN, SHOULD OFFER MANY ADVANTAGESOVER CONVENTIONAL TUNGSTIC ACID DENUDER TUBES AND OTHER METHODS FOR MEASURING GAS-PHASE AMMONIA IN TERMS OF SENSITIVITY, SPEED OF ANALYSIS, SELECTIVITY, EASE OF OPERATION, AND LONG-TERM STABILITY.