Synthesis Of CePO₄-Ni₂P Composite Catalysts For Hydrogenation Reactions

Perusing of cheap and stable catalytic materials which were comparable with precious metals for catalytic hydrogenations has been long for correlating industrial applications,the desire drives us to perform following works in the thesis.（1）Ce³⁺and Ni²⁺were co-bonded by HPO₄^2-in a one-pot solvothermal synthesis system,then obtained precipitates were thermal-treated to get a series of catalysts.With characterizations of ICP-OES,XRD,XPS,SEM and HRTEM,the samples were featured as CePO₄-Ni₂P nanocomposite particles（CePO₄ and Ni₂P particles both in ca.10.0-40.0 nm）（2）Employing these CePO₄-Ni₂P nanocomposites as catalysts for catalytic hydrogenation reactions,it was demonstrated that under the mild reaction conditions such as 0.1 MPa H₂ and 353 K,Phenyl acetylene can be almost fully converted to the desired product（styrene）in ca.89-94%yield on typical（CePO₄）_m-Ni₂P samples（0.12≤m≤1.8）;for Cinamaldehyde（CAL）under 2.0 MPa H₂ and 353 K,the reactant can be converted in high conversion of 72-96%,which was accompanied by the outstanding selectivity（92-99%）to the C=C bond hydrogenation product when controlling molar ratio m in 0.12-4.6 in（CePO₄）_m-Ni₂P nanocomposites.The superior hydrogenation performance were represent for two alkenes and other elevenα,β-unsaturated carbonyl compounds,both the attractive activity and selectivity for these hydrogenation reactions were shown on typical（CePO₄）_m-Ni₂P sample.（3）By chemical adsorption and dynamic analysis,the origin of catalytic performance of the（CePO₄）_m-Ni₂P nanocomposites could be attributed to following aspects:CePO₄ was highly efficient to activate of hydrogen,the unreported feature cooperated with the activation of carbon-chain reactant on Ni₂P to achieve efficient catalytic hydrogenation on（CePO₄）_m-Ni₂P composites,in which,it should be notable that the turnover frequencies for some reaction such as hydrogenation of CAL could be got as 0.06-0.51 s^-1,these were comparable with precious metal catalysts.These findings indicated that（CePO₄）_m-Ni₂P nanocomposites was one kind of excellent,stable,universal and inexpensive catalyst for hydrogenation reactions,which was worthy investigating as a substitute material to precious metal catalysts for many key applications.