Insight into the Effect of Cobalt Substitution on the Catalytic Performance of LaMnO₃ Perovskites for Total Oxidation of Propane

Abstract

Cobalt-substituted LaMnO 3 perovskite catalysts synthesized by the citric acid sol−gel method have been investigated for the total oxidation of propane, as a model for emission control of hydrocarbon volatile organic compounds. Characterization studies demonstrate that a trace of cobalt substitution can enhance the specific surface area, produce abundant reactive oxygen species, and improve low-temperature reducibility, which promote the catalytic activities of La-Co x Mn 1−x O 3 catalysts remarkably. LaCo 0.2 Mn 0.8 O 3 exhibits the highest catalytic activity (T 90 = 355 °C), of which T 90 is 25 °C lower than that of LaMnO 3 . In situ DRIFTS and C 3 H 8 -TPSR results indicate that the adsorption and activation of propane will be accelerated by appropriate Co substitution and acetone and carboxylate species are considered as intermediates involved in propane oxidation. In addition, the influence of water vapor on the catalytic activity of the LaCo 0.2 Mn 0.8 O 3 catalyst for propane oxidation is greater than that of CO 2 , while LaCo 0.2 Mn 0.8 O 3 can sustain robust stability under CO 2 and water vapor atmospheres.

Influence of Cobalt Substitution in LaMnO₃ on Catalytic Propylene Oxidation

“…Further, the oxygen adsorption and the total oxidation of propylene on LaCoO 3 are attributed to propylene's activation energy and the bond strength, with the adsorbent surface greatly influencing the catalytic action for oxidation by these perovskite materials [2]. The observed trend of catalytic activity was similar to the similar work of total propane oxidation published in the very recent work [12], where authors have focused on the reaction kinetics of slightly different compositions LaMn 1-x Co x O 3 system. Unfortunately, to our knowledge, there are very few literature reports available for the total hydrocarbon oxidation studies and their correlation with the structure of this class of LaMn 1x Co x O 3 material systems.…”

Experimental methods in chemical engineering: Temperature programmed surface reaction spectroscopy—TPSR

“…Integrating operando analytical instruments (DRIFTS and Raman, for example) with TPSR will continue to develop in the future. [ 34–38 ]…”

“…Integrating operando analytical instruments (DRIFTS and Raman, for example) with TPSR will continue to develop in the future. [34][35][36][37][38] ACKNOWLEDGEMENT I.E. Wachs acknowledges funding from the Department of Energy, Basic Energy Sciences (FG02-93ER14350) during the writing of this paper.…”

Influence of Structure on Catalytic Properties of La0.7Sr0.3BO3 (B = Mn, Fe, Ni) Perovskite Catalysts in Total Oxidation Reaction of M-Xylene

“…3.6 Received: July 08, 2020; accepted: May 11, 2021 tác. Các công bố cho thấy, các vật liệu perovskit có khả năng xúc tác cho nhiều phản ứng khác nhau như: phản ứng oxi hóa hydrocacbon và các hợp chất hữu cơ dễ bay hơi [1,2], oxi hóa CO [3,4], khử NOx [5], xúc tác quang hóa [6], xúc tác điện hóa [7,8]. Tuy nhiên, việc nghiên cứu có tính qui luật từ phân tích cấu trúc cho đến tính chất xúc tác của hệ vật liệu perovskit biến tính nhiều thành phần La0,7Sr0,3BO3 (B = Mn, Fe, Ni) trong phản ứng oxi hóa hoàn toàn m-xylen thì đến nay chưa thấy có công trình nào công bố.…”