New catalyst for removal of N2O from nitric acid plant tail gases
L. Obalová1, F. Kovanda2, K. Jirátová3
1VSB-Technical University of Ostrava, 17. listopadu 15, 708 33 Ostrava, Czech Republic, Tel.: +420 597 321 532, E-mail: lucie.obalova@vsb.cz,
Institute of Chemical Technology, Prague, Technická 5, 166 28 Prague, Czech Republic, Tel.: +420 220 444 086, E-mail: Frantisek.Kovanda@vscht.cz,
2 Institute of Chemical Process Fundamentals of the ASCR, v. v. i., Rozvojová 135, 165 02 Prague 6, Czech Republic, Tel.: +420 220 390 295, E-mail: jiratova@icpf.cas.cz
Abstract
Multicomponent K-doped Co-Mn-Al mixed oxide deN2O catalysts were prepared by calcination of Co-Mn-Al layered double hydroxide and following impregnation by KNO3. Tuning of the catalyst properties was guided by catalytic tests of N2O decomposition including the effect of water, oxygen and NOx inhibitors, TPR-H2 and in-situ work function measurements. The optimal composition of the catalyst revealed in the laboratory experiments was successfully reproduced in large scale synthesis and shaping. In the pilot plant tests, high output in N2O removal from the tail gases of the nitric plant for 112 days was reached.
Fig. 1: Stability test of Co-Mn-Al mixed oxide with 2 wt% K promoter in pilot plant conditions (VHSV = 8 620 l lbed-1 h-1, p = 6 bar)