A nitrogen-doped porous carbon immobilized noble metal catalyst and its preparation method and application

Abstract

The invention discloses a nitrogen-doped porous carbon-immobilized noble metal catalyst and its preparation method and application. The preparation method includes: (a) combining chitosan, ionic liquid and KCl‑ZnCl 2 The mixture composed of double salts is placed in a tube furnace, and the temperature of the furnace body is raised to 600~1000°C in an atmosphere of continuous inert gas. After holding the temperature for 1~8 hours, a black solid is obtained; (b) Add the black solid to dilute In the acid solution, stir rapidly at room temperature for 1 to 5 hours, and repeat twice to remove the double salt template; (c) After the obtained material is ultrasonically dispersed in the palladium salt solution for 0.5 to 2 hours, NaBH 4 The solution was slowly dropped into the reaction system and stirred for 2 to 6 hours. The solid product obtained was washed with water and dried to obtain the catalyst. The catalyst of the present invention has abundant defect sites, nitrogen content and developed pore structure. At 80°C and 0.1MPa H 2 It exhibits superior catalytic performance for the selective hydrogenation of quinoline derivatives under mild conditions.

Description

technical field [0001] The invention relates to a nitrogen-doped porous carbon immobilized noble metal catalyst and a preparation method and application thereof, belonging to the technical field of catalyst preparation and application. Background technique [0002] Chemoselective hydrogenation of quinolines and their derivatives is a very attractive reaction process, since its hydrogenation products 1,2,3,4-tetrahydroquinolines (py-THQs) are widely used in fine chemicals, pesticides , pharmaceuticals and other bioactive molecules play a very critical role. The hydrogenation process of quinoline derivatives often involves multiple intermediates, and the reaction energy barrier is high, resulting in a slow internal kinetic reaction process, which poses more severe challenges to the production and development of high-performance catalysts. Although noble metal-supported catalysts based on Ru, Rh, Au, Pt, and Pd have shown excellent catalytic performance in the selective hydrog...

AI Technical Summary

Problems solved by technology

However, the problems of low natural abundance, high cost, skeleton collapse, and environmentally unfriendly post-processing of these raw materials have become bottlenecks that limit their wide application.

Therefore, it is urgent to find a new and efficient way to prepare nitrogen-doped porous carbon catalytic materials with high specific surface area and developed pore structure to overcome the aggregation of noble metal nanoparticles under relatively harsh reaction conditions in current heterogeneous catalytic systems. / Drain and deactivation issues

[0004] And because noble metal nanoparticles undergo hydrogenation, oxidation, and coupling reactions in water, alcohols, and other highly polar reaction media, the strong interaction between them and solvent molecules will cause the active components to fall off the surface of the carrier. , poisoning or deactivation; therefore, it is the key of the present invention to search for a catalyst with low cost, strong operability and high stability of noble metal nanoparticles that can meet mass production

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