In situ controllable synthesis method for hydrotalcite-supported Pd nano crystal catalysts with different morphologies and application of hydrotalcite-supported Pd nano crystal catalysts in catalysis of Heck reaction

A synthetic method, hydrotalcite technology, applied in chemical instruments and methods, physical/chemical process catalysts, metal/metal oxide/metal hydroxide catalysts, etc., can solve the limitations of exploration, uneven morphology of Pd nanoparticles, etc. problem, to achieve the effect of good dispersion, uniform shape and uniform size

Active Publication Date: 2013-07-17
BEIJING UNIV OF CHEM TECH
View PDF2 Cites 10 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the Pd nanoparticles in these supported Pd catalysts often exhibit heterogeneous morphology, which limi...

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • In situ controllable synthesis method for hydrotalcite-supported Pd nano crystal catalysts with different morphologies and application of hydrotalcite-supported Pd nano crystal catalysts in catalysis of Heck reaction
  • In situ controllable synthesis method for hydrotalcite-supported Pd nano crystal catalysts with different morphologies and application of hydrotalcite-supported Pd nano crystal catalysts in catalysis of Heck reaction
  • In situ controllable synthesis method for hydrotalcite-supported Pd nano crystal catalysts with different morphologies and application of hydrotalcite-supported Pd nano crystal catalysts in catalysis of Heck reaction

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0020] 1. Prepare nitrate intercalated hydrotalcite by nucleation / crystallization isolation method, the specific method is: weigh 25.64g of Mg(NO 3 ) 2 ·6H 2 O and 18.75g of Al(NO 3 ) 3 9H 2 O dissolved in 80ml of deCO 2 Prepare mixed salt solution A in deionized water, weigh 12.00g NaOH and dissolve in 100mL deCO2 2 Make alkaline solution B in deionized water, add solutions A and B to the fully back-mixed liquid membrane reactor at the same time, the working voltage is 140V, the rotor speed is 5000rpm, back-mix for 2min, and transfer the obtained white slurry to the polytetrafluoroethylene reactor In the process, hydrothermal crystallization at 110°C for 24h, followed by washing three times with deionized water, and drying at 70°C for 12 hours to obtain nitrate intercalated hydrotalcite.

[0021] 2. Intercalate 0.45g of nitrate hydrotalcite with 0.05g of Na 2 PdCl 4, 0.6g of KI, and 0.82g of polyvinylpyrrolidone with a molecular weight of 10,000-20,000 were added to 1...

Embodiment 2

[0025] 1. Same as embodiment 1.

[0026] 2. Intercalate 0.50g of nitrate with 0.06g of Na 2 PdCl 4 0.82g of polyvinylpyrrolidone with a molecular weight of 50,000-60,000 was added to a mixed solution of 16ml of ethylene glycol and 4ml of water and mixed evenly, then stirred and reacted for 5 hours in an oil bath at 90°C, and the obtained product was centrifuged with acetone for 1 Centrifuge twice with a mixed solution of ethanol and deionized water with a volume ratio of 2:1, and dry in vacuum to obtain a Pd nanocrystalline catalyst with a hydrotalcite-supported truncated octahedral shape, which is denoted as Pd-TROCs / LDH, The loading of Pd nanocrystals is 3.12wt%.

[0027] 3. The Pd-TROCs / LDH prepared above was applied to catalyze the Heck coupling reaction. The reaction conditions were: disperse 60 mg of Pd-TROCs / LDH in 15 mL of N,N-dimethylformamide, and then add 1 mmol styrene and 1.2mmol chlorobenzene, bromobenzene or iodobenzene, N 2 In the environment, the reaction...

Embodiment 3

[0030] 1. Same as embodiment 1.

[0031] 2. Intercalate 0.45g of nitrate hydrotalcite with 0.05g of Na 2 PdCl 4 , 0.60g of KCl, and 0.82g of polyvinylpyrrolidone with a molecular weight of 40000-50000 are added together into 15ml of a mixed solution of ethylene glycol and water with a volume ratio of 0.2 and mixed uniformly, then transferred to a 20ml polytetrafluoroethylene reactor, After reacting under hydrothermal conditions at 115°C for 5 hours, the obtained product was centrifuged once with acetone, then centrifuged three times with a mixed solution of ethanol and deionized water with a volume ratio of 1:1, and dried in vacuum to obtain a hydrotalcite-loaded triangular The Pd nanocrystalline catalyst with sheet-like morphology is denoted as Pd-TRPLs / LDH, and the loading of Pd nanocrystals is 3.01wt%.

[0032] 3. The above prepared Pd-TRPLs / LDH was applied to catalyze the Heck coupling reaction. The reaction conditions were as follows: 60 mg of Pd-TRPLs / LDH was disperse...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention belongs to the technical field of preparation of supported nano crystal catalysts and in particular relates to in situ controllable equipment for hydrotalcite-supported Pd nano crystal catalysts with different morphologies and research on activity of the hydrotalcite-supported Pd nano crystal catalysts in catalysis of a Heck coupled reaction. The synthesis process of the hydrotalcite-supported Pd nano crystal catalyst comprises the following step of: growing Pd nano crystals with different morphologies (cube, truncated octahedron and triangle) and different exposed crystal faces ({111} and {100}) in situ on the surface of hydrotalcite by adopting a one-pot synthesis method under the conditions of different reducing agents (polyvinylpyrrolidone and ethylene glycol) and surface capping agents (I<->, Cl<-> and polyvinylpyrrolidone) with a mixed solution composed of Na2PdCl4 and nitrate intercalation hydrotalcite. Besides, the synthesized hydrotalcite-supported Pd nano crystal catalysts with different morphologies are used for evaluating the Heck coupled reaction and researching a catalytic activity sequence of different exposed Pd crystal faces of the hydrotalcite-supported Pd nano crystal catalysts, and a foundation is laid for further reasonably designing an efficient supported nano crystal catalyst.

Description

technical field [0001] The invention belongs to the technical field of preparation of supported nano-crystal catalysts, and in particular relates to the in-situ controllable synthesis of Pd nano-crystal catalysts with different shapes supported by LDH, and researches on its catalytic Heck coupling reaction activity. Background technique [0002] In the past two decades, metal nanocrystals have attracted extensive attention of researchers due to their huge potential applications in the fields of catalysis, electronics, optics, and biology. The morphology and size of these nanocrystals often have a great impact on their physicochemical properties, and in structure-sensitive catalytic reactions, their activity and selectivity often depend on the specific morphology or crystal facets exposed. It can be seen that the synthesis of nanocrystals with different morphologies can not only be used to theoretically study their existing structure-activity relationship, but also enhance or...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): B01J23/44C07C15/44C07C2/88
Inventor 陆军张强徐景李双德
Owner BEIJING UNIV OF CHEM TECH
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap