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

Abstract:

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.

• Periodical: Materials Science Forum (Volumes 743-744)
• Pages: 449-454
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.743-744.449
• Online since: January 2013
• Authors: Zhi Juan Gao, Wei Ren Bao, Li Ping Chang, Jian Cheng Wang
• Keywords: Cordierite, Cu-SAPO-34, NO_x, SCR, Ultrasonic

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