Stability of Sn–Pd-Kaolinite catalyst during heat treatment and nitrate reduction in continuous flow reaction. (February 2020)

• Record Type: Journal Article
• Authors: Hamid, Shanawar; Golagana, Satwika; Han, Seunghee; Lee, Giehyeon; Babaa, Moulay-Rachid; Lee, Woojin
• Is Part Of: Chemosphere. Volume 241(2020)
• Publication Date: 2020-02
• Subjects: catalytic nitrate reduction -- Kaolinite support -- Sn–Pd bimetallic catalyst -- Catalytic durability -- Continuous nitrate reduction; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2019.125115
• Languages: English
• ISSNs: 0045-6535

Abstract

Abstract: In this study, a novel and highly reactive Sn–Pd catalyst supported by environmentally benign kaolinite (Sn–Pd-kaolinite) was developed and evaluated for stability for effective nitrate (NO3 − ) reduction in batch and continuous mode. Complete NO3 − removal with fast reduction kinetics (k = 18.16 × 10 −2 min −1 ) and 71% selectivity toward N2 were achieved by the Sn–Pd-kaolinite catalyst during batch reactions. During continuous tests, 100% NO3 − removal and 80% N2 was achieved for 60 h. However, NO3 − removal efficiency gradually decreased to 80% in170 h. The catalyst was then successfully regenerated in the system by increasing H2 flow which achieved a complete NO3 − removal again. The metal leaching from catalyst surface was negligible (Sn 0.01% and Pd 0.006%) and the structure was stable during the continuous test, confirming that the Sn–Pd-Kaolinite catalyst had a superior reaction kinetics and operational durability. Graphical abstract: Image 1 Highlights: A novel Sn–Pd-kaolinite catalyst was synthesized for an accelerated NO3 − reduction. Complete NO3 − removal with high N2 selectivity was achieved by the bimetallic catalyst. The catalyst showed a remarkable durability and stability in a continuous reactor system. Catalyst regeneration was successfully implemented with an increased H2 flow.