A CATALYTIC THERMAL MANAGEMENT SYSTEM FOR HYDROGEN-FUELED INJECTION VEHICLES

A COOLING STRATEGY UTILIZING THE ENDOTHERMICITY OF THE PARA- TO ORTHO-HYDROGEN CONVERSION HAS POTENTIAL FOR MEETINGTHE REQUIREMENTS OF AN ADVANCED SUBSYSTEM FOR THERMAL MANAGEMENT IN HYDROGEN-FUELED INJECTION VEHICLES. THE PROPOSED EFFORT WILL DETERMINE THE FEASIBILITY OF DEVELOPINGSUCH A COOLING SYSTEM USING NEW ALUMINA-SUPPORTED FORMULATIONS AS CATALYSTS FOR THE INTERCONVERSION OF PARA- AND ORTHO-HYDROGEN. OUR APPROACH INCLUDES PREPARATION OF NEW CATALYST MATERIALS CONTAINING PARAMAGNETIC TRANSITION METAL IONS DISPERSED IN HIGH SURFACEAREA, POROUS ALUMINA. THE NEW CATALYST MATERIALS WILL BE PREPARED USING VARIOUS METHODS INCLUDING 1) SUPERHOMOGENEOUSCOPRECIPITATION, 2) SOL-GEL FORMATION, 3) SUPPORT IMPREGNATION, AND 4) COMBINATIONS OF THESE. THE NEWLY PREPARED MATERIALS WILL BE CHARACTERIZED BY DETERMINATION OF 1) METAL ION CONTENT, 2) TOTAL SURFACE AREA BY NITROGEN PHYSISORPTION, 3) TOTAL PORE VOLUME AND AVERAGE PORE DIAMETER BY NITROGEN VOLUMETRIC METHODS, AND 4) MAGNETIC SUSCEPTIBILITIES DETERMINED USING THE FARADAY METHOD. ACTIVATION TECHNIQUES WILL BE VARIED FOR EACH NEW CATALYST MATERIAL TO DETERMINE IF THEY INFLUENCE CATALYTIC ACTIVITIES. THE CATALYTIC ACTIVITIES OF THESE MATERIALS WILL BE EVALUATED BY MEASURING THE RATE OF CONVERSION OF ORTHO- TO PARA-HYDROGEN UPON COOLING FROM AMBIENT LABORATORY TEMPERATURES TO LIQUID NITROGEN TEMPERATURE (77 DEGREES K).