Catalytic decomposition of N2O over RhOx supported on metal phosphates

RhOx/M-P-O (M = Mg, Al, Ca, Fe, Co, Zn, La) catalysts were tested in N2O decomposition. RhOx/Ca-P-O showed the highest activity, achieving complete N2O conversion at 300 degrees C. RhOx/La-P-O is the second most active catalyst, achieving almost complete conversion at 375 degrees C. RhOx/Mg-P-O, RhOx/Co-P-O, and RhOx/Al-P-O showed lower activities, whereas RhOx/Fe-P-O and RhOx/Zn-P-O were completely inactive. The high activity of RhOx/Ca-P-O is ascribed to the presence of very small RhOx particles, more basic sites, and the easiness of desorbing O-2 at low temperatures. The inhibiting effects of co-fed O-2 and/ or H2O on the catalytic activity of RhOx/Ca-P-O are reversible. (C) 2015 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.