Abstract
Iron-substituted MFI, Y and USY zeolites prepared by two preparation routes—classical ion exchange and the ultrasound modified ion-exchange method—were characterised by micro-Raman spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), and ultraviolet (UV)/visible diffuse reflectance spectroscopy (UV/Vis DRS). Ultrasound irradiation, a new technique for the preparation of the metal salt suspension before incorporation to the zeolite structure, was employed. An experimental study of selective catalytic reduction (SCR) of NO with NH3 on both iron-substituted reference zeolite catalysts and those prepared through the application of ultrasound conducted during an ion-exchange process is presented. The prepared zeolite catalysts show high activity and selectivity in SCR deNOx abatement. The MFI-based iron catalysts, especially those prepared via the sonochemical method, revealed superior activity in the deNOx process, with almost 100% selectivity towards N2. The hydrothermal stability test confirmed high stability and activity of MFI-based catalysts in water-rich conditions during the deNOx reaction at 450 °C.
Highlights
NOx compounds (NO and NO2 ) are products of the internal combustion of fuels
The application of ultrasound radiation has been proposed as a new methodology for the preparation of iron-loaded zeolite catalysts
The zeolites used in this work were synthesised in a laboratory environment in accordance with the well-known route, resulting in three types of zeolites being obtained
Summary
NOx compounds (NO and NO2 ) are products of the internal combustion of fuels. The problem of their removal from exhaust gas is crucial, mostly because of their negative environmental impact [1,2,3].Combustion in diesel vehicles and power plants can be considered to be their main sources. NOx compounds (NO and NO2 ) are products of the internal combustion of fuels. The problem of their removal from exhaust gas is crucial, mostly because of their negative environmental impact [1,2,3]. Combustion in diesel vehicles and power plants can be considered to be their main sources. The process is a lean burn, so there is a significant amount of unreacted O2 in the exhaust gases. The emission limits for NOx concern both stationary and mobile sources, and the maximum allowed concentration level in the air has become more restricted in recent years [4,5]. NOx removal is important due to the compounds’ behaviour as catalysts for photochemical oxidation, and because
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
