Catalytic performance and mechanistic study of toluene combustion over the Pt-Pd-HMS catalyst. (21st September 2019)

• Record Type: Journal Article
• Authors: Zhang, Qiulin; Su, Weikang; Ning, Ping; Liu, Xin; Wang, Huimin; Hu, Jia
• Is Part Of: Chemical engineering science. Volume 205(2019)
• Page Start: 230
• Page End: 237
• Publication Date: 2019-09-21
• Subjects: Pt-Pd -- HMS -- Toluene -- Catalytic combustion -- In-situ DRIFTS; Chemical engineering -- Periodicals; Génie chimique -- Périodiques; Chemical engineering; Periodicals; Electronic journals; 660
• DOI: 10.1016/j.ces.2019.04.047
• Languages: English
• ISSNs: 0009-2509

Abstract

Graphical abstract: Pt-Pd-HMS catalyst was obtained by one-pot method. Benzoic route and aliphatic carbonyl route coexisted for the catalytic combustion of toluene over the active sites of one-pot synthesized Pt-Pd-HMS, while benzoic was the major pathway of toluene catalytic combustion over the active sites of impregnated Pt-Pd/HMS. Simultaneous generation of benzoate and aliphatic compounds accelerated toluene combustion over the Pt-Pd-HMS catalyst. Highlights: One-pot synthesized Pt-Pd-HMS exhibits optimal performance with T90 = 179 °C. One-pot approach and bi-metallic strategy reduced metal particle size. Generation of benzoate and aliphatic species accelerate catalytic performance. Abstract: Pt-Pd-HMS catalyst had been prepared by a one-pot approach and tested for toluene combustion. Comparing with conventional impregnated Pt-Pd/HMS ( Ea = 111.41 kJ/mol, Pt-Pd particle size = 23.4 nm), the Pt-Pd-HMS exhibited lower activation energy ( Ea = 80.23 kJ/mol) and smaller Pt-Pd particle size (6.3 nm). Moreover, surface Pt 0 /Pttotal of the Pt-Pd-HMS (52.8%) was higher than that of the Pt-Pd/HMS (46.8%), and Pt-Pd-HMS obtained an optimal catalytic performance with T90 = 179 °C at a GHSV = 26, 000 mL/(g·h). In-situ DRIFTS indicated that simultaneous generation of benzoate species and aliphatic compounds as intermediates occurred on the active sites of Pt-Pd-HMS. In contrast, the intermediates of toluene combustion on the active sites of Pt-Pd/HMS were dominated by benzoates.