Detailed Investigation of Sm2O3 Catalysts with Different Morphologies for Oxidative Coupling of Methane. Issue 31 (17th August 2021)

• Record Type: Journal Article
• Authors: Özdemir, Hasan
• Is Part Of: ChemistrySelect. Volume 6:Issue 31(2021)
• Page Start: 7999
• Page End: 8006
• Publication Date: 2021-08-17
• Subjects: heterogeneous catalysis -- morphology -- oxidative coupling -- samarium -- surface area; Chemistry -- Periodicals; 540.5
• DOI: 10.1002/slct.202101727
• Languages: English
• ISSNs: 2365-6549

Abstract

Abstract: Sm2 O3 catalysts with different morphologies (nanoparticle, nanorod, hollow nanosphere, nanofiber, flower‐like) were synthesized and tested for the oxidative coupling of methane. The results obtained showed that increasing specific surface area reduced the activity, C2 selectivity and, thus the yield. It was observed that the reaction initiation temperature was dependent on the total or partial oxidation of methane, which produced the heat for the initiation of the reaction. The effect of temperature on catalytic performance was relatively low at lower temperatures (<600 °C) than at higher temperatures (>700 °C). High reaction temperatures (>700 °C) decreased the C2 selectivity, lower temperatures were found beneficial to achieve higher C2 selectivity and yield as expected. Hollow nanosphere morphology showed the highest activity and selectivity at 450 °C and yielded 10.5 % C2 under high space velocity. The highest C2 yield (11.8 %) was obtained at 600 °C with nanoparticle morphology. Considering the results at the conditions that full oxygen conversion was attained, it was found that the C2 selectivity and yield decreased with the nanoparticle>flower‐like>nanorod and nanosphere>nanofiber sequence. Abstract : Catalytic activity tests on Sm2 O3 catalysts with different morphologies for oxidative coupling of methane clearly showed that the catalytic performance depends mainly on the specific surface area and decreases with increasing surface area. The C2 selectivity and yield decreased with the nanoparticle>flower‐like>nanorod and nanosphere>nanofiber sequence. The results were obtained at 540 °C in which reaction initiated and oxygen conversions were complete.