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Từ khóa:
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Glycerol, Lacticacid, Cocatalyst, Alloyeffects, Transferhydrogenation
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Danh mục:
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ScienceDirect - Springer - Bookboon...
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Môn học:
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(E-journals) ScienceDirect - Springer - Bookboon...
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Tóm tắt theo nội dung:
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BimetallicNi-CocatalystssupportedonnanosizedCeO2werepreparedandinvestigatedasheterogeneouscat-alysts for the transfer hydrogenation between glycerol and various H2acceptors (levulinic acid, benzene, ni-trobenzene, 1-decene, cyclohexene) to selectively produce lactic acid (salt) and the target hydrogenated com-pound. The bimetallic NiCo/CeO2catalyst showed much higher activity than the monometallic Ni or Cocounterparts(withequaltotalmetalmass),thusindicatingstrongsynergeticeffects.TheinteractionbetweenthemetallicsitesandtheCeO2supportwasthoroughlycharacterisedbymeansoftransmissionelectronmicroscopy(TEM), scanning transmission electron microscopy (STEM), energy-dispersive X-ray spectroscopy (EDX) map-ping, X-ray photoelectron spectroscopy (XPS), hydrogen-temperature programmed reduction (H2-TPR) and X-ray diffraction (XRD). Combining characterisation and catalytic results proved that the Ni species are in-trinsically more active than Co species, but that incorporating Co into the catalyst formulation prevented theformation of large Ni particles and led to highly dispersed metal nanoparticles on CeO2, thus leading to theobservedenhancedactivityforthebimetallicsystem.Thehighestyieldoflacticacid(salt)achievedinthisworkwas93%at97%glycerolconversion(160°C,6.5hat20barN2,NaOH:glycerol=1.5).TheNiCo/CeO2catalystalso exhibited high activity and selectivity towards the target hydrogenated products in the transfer hydro-genation reactions between glycerol and various H2acceptors. Batch recycle experiments showed good reusa-bility,withretentionof80%oftheoriginalactivityafter5runs
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