High-Silica PD-Based Small Pore Zeolite Catalysts for Low Temperature CH4 Oxidation

High silica (silicon/aluminum molar ratios > 30), small pore (-0.36-0.45 nm pore apertures) zeolite catalysts for CH4 remediation in low temperature (< 400 °C), high water vapor environments (5 - 10%), such as those associated with natural gas vehicle exhaust streams. The catalysts can achieve T90's below 400 °C and remain hydrothermally stable over extended periods of time. The zeolite catalyst may be made by a molar gel composition of the appropriate reagents that is heated in a reaction vessel and then subjected to ion exchange with a source of palladium to achieve less than 2 weight percent loading of palladium in the zeolite.