Chemical interference effects with copper-doped mordenite for dilute methane emissions mitigation

Area of Science:

• Catalysis
• Environmental Science
• Materials Science

Background:

• Methane is a potent, short-lived climate pollutant targeted for emission reduction.
• Catalytic conversion of methane is a promising strategy, but catalyst tolerance to interferents is crucial.
• Copper-doped mordenite catalysts are being explored for methane conversion applications.

Purpose of the Study:

• To investigate the impact of common atmospheric components on copper-doped mordenite catalysts for methane conversion.
• To assess the catalyst's efficacy in the presence of water vapor, alkanes, hydrogen sulfide, ammonia, and nitric oxide.
• To determine the feasibility of using these catalysts for emission control in various industrial and natural environments.

Main Methods:

• Experimental investigation of copper-doped mordenite catalysts.
• Exposure of catalysts to controlled concentrations of methane and potential interferents (water vapor, alkanes, H2S, NH3, NO).
• Measurement of methane conversion efficiency under varying conditions, including temperature.

Main Results:

• Water vapor, nitric oxide, and hydrogen sulfide reduced methane conversion efficiency, with effects mitigated by higher temperatures.
• Alkanes (up to 100 ppm total) and ammonia (up to 20 ppm) did not inhibit methane conversion.
• Copper zeolites effectively converted light alkanes to CO2, indicating potential for emission control.

Conclusions:

• Copper-doped mordenite exhibits potential for methane emission control, particularly in environments with humidity, sulfur, and nitrogen compounds.
• Catalyst performance is sensitive to specific interferents like H2O, NO, and H2S, but temperature plays a mitigating role.
• The ability to convert light alkanes further enhances the applicability of these catalysts in effluent streams.