摘要
One-step synthesis of 2-propylheptanol(2-PH)from n-pentanal via a reaction integration of n-pentanal self-condensation and successive hydrogenation is of great significance for it can simplify process flow and reduce energy consumption.The key to promotion of 2-PH selectivity is to enhance the competitiveness of n-pentanal self-condensation with respect to its direct hydrogenation.For this purpose,a core–shell structured Ni/SiO_(2)@TiO_(2) catalyst was designed and prepared.With the precise architecture of this core–shell structured catalyst,n-pentanal can be firstly in contact with TiO_(2) to 2-propyl-2-heptenal(2-PHEA)while the direct hydrogenation to n-pentanol can be effectively inhibited,and then 2-PHEA diffuses into the core of Ni/SiO_(2) and is hydrogenated to 2-PH.The spatial threshold of the core–shell catalyst significantly enhanced its catalytic performance;a 2-PH selectivity of 77.9%was reached with a 100%npentanal conversion.The 2-PH selectivity is much higher than that obtained by employing Ni/TiO_(2) catalyst.Furthermore,the reaction kinetics of one-step synthesis of 2-PH from n-pentanal catalyzed by Ni/SiO_(2)@TiO_(2) was studied and its kinetic model was established which is useful for reactor design and scale-up.
基金
This work was financially supported by the National Natural Science Foundation of China(21978066,21506046)
Natural Science Foundation of Hebei Province(B2020202048,B2018202220)
Natural Science Foundation of Tianjin City(18JCYBJC42600).
