Acetylene coupling with ethylene dichloride,which uses both coal and oil resources,is attractive for sustainable PVC manufacturing.Herein,highly active and stable carbon nitride‐based catalysts were developed by a no...Acetylene coupling with ethylene dichloride,which uses both coal and oil resources,is attractive for sustainable PVC manufacturing.Herein,highly active and stable carbon nitride‐based catalysts were developed by a novel pre‐oxidation‐pyrolysis process,affording unprecedented dehydrochlorination activity with good durability.The best‐performing system was further modified with different precious metals(Au,Pt,and Ru)to promote the hydrochlorination chemistry between the in‐situ formed hydrogen chloride and acetylene co‐feed.The presence of metal centers intensifies the hydrochlorination activity but weakens the dehydrochlorination ability due to competitive adsorption between the two reactants at the metal sites.Superior coupling performance was achieved over C_(3)N_(4)/AC and single‐atom Au/C_(3)N_(4)/AC catalysts in cascade reactors.Our results strongly suggest that dehydrochlorination is an essential step in the coupling reaction,and the activation of acetylene and ethylene dichloride molecules requires different active sites that should be engineered in future work.展开更多
8-Aminoquinoline nickel dichloride and bis(cyclopentadienyl)zirconium dichloride (Cp_2ZrCl_2) were supportedsimultaneously on silica to produce branched polyethylene successfully by combined polymerization. The suppor...8-Aminoquinoline nickel dichloride and bis(cyclopentadienyl)zirconium dichloride (Cp_2ZrCl_2) were supportedsimultaneously on silica to produce branched polyethylene successfully by combined polymerization. The supportedpolymerization results showed that the molecular weight of polyethylene increased while the molecular weight distributionbecame wider and the molecular chains of oligomers remaning in the final solution became shorter as compared to theoligomers obtained in polymerization processes with pure 8-aminoquinoline nickel dichloride catalysis, as well as theCp_2ZrCl_2 and nickel combination system. With decreasing amount of Ni catalyst in the supported catalyst, the molecular chains of oligomers in the resulting solution became shorter, while α-olefin selectivity increased.展开更多
文摘Acetylene coupling with ethylene dichloride,which uses both coal and oil resources,is attractive for sustainable PVC manufacturing.Herein,highly active and stable carbon nitride‐based catalysts were developed by a novel pre‐oxidation‐pyrolysis process,affording unprecedented dehydrochlorination activity with good durability.The best‐performing system was further modified with different precious metals(Au,Pt,and Ru)to promote the hydrochlorination chemistry between the in‐situ formed hydrogen chloride and acetylene co‐feed.The presence of metal centers intensifies the hydrochlorination activity but weakens the dehydrochlorination ability due to competitive adsorption between the two reactants at the metal sites.Superior coupling performance was achieved over C_(3)N_(4)/AC and single‐atom Au/C_(3)N_(4)/AC catalysts in cascade reactors.Our results strongly suggest that dehydrochlorination is an essential step in the coupling reaction,and the activation of acetylene and ethylene dichloride molecules requires different active sites that should be engineered in future work.
基金This work was also supported by the Core Research for Engineering Innovation KGCX2-203 of the Chinese Academy of Sciences, National Natural Science Foundation of China (No. 20272062) and the "One Hundred Talents" Fund foWen-Hua Sun.
文摘8-Aminoquinoline nickel dichloride and bis(cyclopentadienyl)zirconium dichloride (Cp_2ZrCl_2) were supportedsimultaneously on silica to produce branched polyethylene successfully by combined polymerization. The supportedpolymerization results showed that the molecular weight of polyethylene increased while the molecular weight distributionbecame wider and the molecular chains of oligomers remaning in the final solution became shorter as compared to theoligomers obtained in polymerization processes with pure 8-aminoquinoline nickel dichloride catalysis, as well as theCp_2ZrCl_2 and nickel combination system. With decreasing amount of Ni catalyst in the supported catalyst, the molecular chains of oligomers in the resulting solution became shorter, while α-olefin selectivity increased.