In-situ Synthesis of Cu-SAPO-34/Cordierite with Ultrasonic Treatment and Its Property of NOx Removal

摘要

A Cu-SAPO-34/cordierite monolithic catalyst was prepared by in-situ hydrothermal method.The effects of ultrasonic treatment were mainly investigated during the preparing process.The removal of NOX was evaluated using a fixed-bed reactor.X-ray diffraction,scanning electron microscopy were used to characterize the samples showing that the crystallinity of Cu-SAPO-34 molecular sieve have increased after ultrasonic treatment.The Cu-SAPO-34/cordierite prepared by ultrasonic treatment showed higher de-NOx activity and stronger anti-aging property.NOx conversion could reach more than 80％ between 440 and 560°C over the fresh Cu-SAPO-34/cordierite catalyst with ultrasonic treatment (600 W,2 h) and the highest conversion was 86％,however,the highest conversion was only 76％ over the Cu-SAPO-34/cordierite catalyst without ultrasonic treatment.After aging (treated for 15 h at 720 °C in the presence of 200 ppm SO2 and 10％ vapor),NOx conversion reached more than 45％ between 400 and 520 °C over the catalyst with ultrasonic treatment and the highest conversion was 57％,however,the highest conversion was only 43％ over the catalyst without ultrasonic treatment.The XRD and SEM results indicated that the structure and morphology of Cu-SAPO-34/cordierite monolithic catalyst kept in good condition after aging.