Particle & Particle Systems Characterization, Vol.31, No.1, 110-120, 2014
Microwave Synthesis of LTL Zeolites with Tunable Size and Morphology: An Optimal Support for Metal-Catalyzed Hydrogen Production from Biogas Reforming Processes
Here, a method is described for the synthesis of Linde type L (LTL) zeolite under microwave-assisted hydrothermal conditions, and its behavior as a support for heterogeneously catalyzed hydrogen production is detailed. Microwave heating reduces the reaction time and improves the quality of the LTL zeolite crystals in comparison to those obtained using conventional ovens. The size and morphology of zeolite can be finely modulated by the composition of the gel and reaction conditions (heating rate, static/dynamic conditions, aging, reaction time, etc). The physicochemical properties of the synthesized LTL zeolites make them appropriate catalyst supports for reforming reactions in which high hydrogen production yields are desired. Therefore, rhodium- and nickel-based bimetallic catalysts are prepared in order to be tested by dry and oxidative biogas reforming processes at 800 degrees C and atmospheric pressure for hydrogen production. For all the catalysts tested, except for the sodium-exchanged disc-shaped zeolite, hydrogen yields close to the predicted by the equilibrium conversion are reached.