Effect of Metal‐Support Interactions in Mixed Co/Al Catalysts for Dry Reforming of Methane

Abstract

Composite Co/Al oxide materials were prepared via flame spray pyrolysis and examined as catalysts for the dry reforming of methane. The interaction between the metal (Co) and the support (Al-oxide) was regulated by varying the Co : Al ratio and its influence on catalyst performance studied. The synthesis of materials with a Co content of 30 mol % (Co 3 Al 7 ) promoted the formation of readily reduced and highly-dispersed Co particles. This, in combination with a high relative surface basicity, contributed to Co 3 Al 7 delivering a high and stable activity towards the dry reforming reaction. The formation of bulk Co 3 O 4 particles, which exhibit weak interactions with the support material, in samples with a Co content of 50 (Co 5 Al 5 ) and 70 mol % (Co 7 Al 3 ) caused rapid catalyst deactivation via coking. The findings demonstrate the importance of metalsupport interactions between the Co catalyst and Al-oxide support for the activity and selectivity in the dry reforming of methane. Highly dispersed Co deposits and high support basicity, induced by an ideal FSP Co : Al synthesis ratio, are key to delivering an active and stable catalyst for the dry reforming of methane.[a] Dr.

Looking into More Eyes Combining In Situ Spectroscopy in Catalytic Biofuel Upgradation with Composition-Graded Ag–Co Core–Shell Nanoalloys

“…The shoulder peak mainly correlates to the reduction of CoO into metallic cobalt; whereas the second peak is generated due to the reduction of cobalt species, which strongly interacts with alumina primarily cobalt aluminate species, which is also in good agreement with Goula et al for Co supported on the γ alumina catalyst . The absence of an asymmetric peak at a lower-temperature range (250–600 °C) strengthened the formation of CoAl 2 O 4 instead of Co 3 O 4 , which is mainly composed of two peaks: 250–400 °C and 400–600 °C for Co 3 O 4 to CoO and CoO to metallic Co, respectively . On the other hand, for the 3Ag–10Co catalyst, the lower-temperature peak corresponds to the reduction of Ag 2 O to metallic Ag, which is observed for all silver-incorporated catalysts (except 5Ag–15Co) .…”

“…44 The absence of an asymmetric peak at a lower-temperature range (250−600 °C) strengthened the formation of CoAl 2 O 4 instead of Co 3 O 4 , which is mainly composed of two peaks: 250−400 °C and 400−600 °C for Co 3 O 4 to CoO and CoO to metallic Co, respectively. 45 On the other hand, for the 3Ag−10Co catalyst, the lower-temperature peak corresponds to the reduction of Ag 2 O to metallic Ag, which is observed for all silverincorporated catalysts (except 5Ag−15Co). 46 The inclusion of silver affects the lower shifting of the Co reduction temperature, which was also previously investigated by Fujimoto et.al.…”

Plasma Treating Mixed Metal Oxides to Improve Oxidative Performance via Defect Generation

“…Titanium isopropoxide (TTIP, Sigma Aldrich, St. Louis, MO, USA) and hexamethyldisiloxane (HMDSO, Sigma Aldrich) in absolute ethanol were mixed with molar concentration of 1.194 M and 0.066 M, respectively, to give a Si:Ti molar ratio of 1:9. The precursor mixture was then used to prepare a mixed SiO 2 /TiO 2 material (denoted as SiTi) with an FSP setup, which has been described previously [25]. After synthesis, the SiTi was hydrogenated in a tube furnace (Carbolite, HST 12/400, 2000 W, Hope Valley, UK) by heating to 500 °C at a rate of 5 °C/min under a 50 mL/min flow of 10% H 2 (N 2 balance).…”

Preparation of Vermiculite‐based Molecular Sieve‐Supported Ni‐Co Alloy Catalyst Assisted by Oleic Acid and Application in Dry Reforming of Methane

“…For Co‐oa/VSiO 2 catalyst, there are two peaks at 316 °C and 790 °C, which are attributed to the reduction peaks of CoO and cobalt silicate, respectively [29] . Cobalt silicate has a larger interaction with the support, so it is more difficult to reduce [30] …”

“…[29] Cobalt silicate has a larger interaction with the support, so it is more difficult to reduce. [30]…”