Novel binderless zeolite-coated monolith reactor for environmental applications

A novel structured catalyst based on a binderless zeolite film was developed onto a cordierite monolith. The zeolitic film was obtained performing a binderless washcoating which was followed by a hydrothermal treatment, which resulted in a coating with hybrid physicochemical properties, having a porous washcoat-like microstructure with an intergrowth between the aggregates. This combination confers to the zeolite coating an open structure which is an advantage of washcoats and a high mechanical stability characteristic of the zeolite growths. It should be emphasized that these desired properties are obtained without the use of binders. The physico-chemical properties were investigated through MIP (mercury intrusion porosimetry), SEM (scanning electron microscopy), ultrasonic adherence tests, NO-TPD (temperature-programmed desorption of NO) and EPMA (electron probe microanalysis). The catalytic properties of the monolith were evaluated in the selective catalytic reduction of NOx at high spatial velocities, showing promising results.