Design of earth-abundant Ni3ZnC0.7@Ni@C catalyst for selective butadiene hydrogenation
The pursuit of developing catalysts from earth-abundant materials to supplant those based on pre-cious metals is of paramount importance in selective hydrogenations.While nickel-based systems have shown promise in the selective hydrogenation of butadiene,their practical applications are hampered by severe deactivation issues due to coke deposition and excessive hydrogenation.Here,a novel catalyst,Ni3ZnC0.7@Ni@C,is ingeniously engineered through the controlled oxidation of Ni3ZnC0.7@C.This catalyst is characterized by small Ni0 ensembles elegantly embellishing the Ni3ZnC0.7 nanoparticles,all encased within porous carbon shells.The evolutions of this catalyst,in terms of composition and structure during the oxidation process,is meticulously observed and characterized using a spectrum of advanced techniques.The Ni3ZnC0.7@Ni@C catalyst exhibits out-standing activity and stability in the hydrogenation of butadiene,surpassing other Ni-based sys-tems,including its precursor Ni3ZnC0.7@C and other previously documented catalysts such as Ni3InC0.5 and the Ni3ln alloy.A pivotal finding of this research is the self-limiting behavior of coke deposition in the initial reaction stages.This intriguing phenomenon not only curbs further deacti-vation but also signifiicantly enhances butene production,maintaining operational stability for an impressive duration of 80 hours.This discovery underscores the advantageous role of in situ gener-ated'soft'cokes in augmenting the selectivity and stability of the catalyst,which is particularly en-lightening for other catalytic processes that are similarly afflicted by coking issues,thereby opening avenues for further in-depth investigations in this field.
NETL
NSTL
万方数据
