Dehalogenation degradation method for halogenated pyridine compound

A technology of halogenated pyridines and compounds, applied in the field of dehalogenation and degradation of halogenated pyridines, which can solve the problems of selectivity, poor safety, large equipment investment, and long process flow, etc., to improve selectivity and toxicity resistance , high safety and high reactivity

Inactive Publication Date: 2016-04-20
QUZHOU UNIV
View PDF10 Cites 5 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0006] The above methods all remove the halogen atoms on the aromatic ring through catalytic hydrogenation, which can achieve the purpose of reducing compound pollution, and the treated pollutants can realize resource reuse, but using H 2 The catalytic hydrogenation technology as a reducing agent has disadvantages such as selectivity and poor safety, and requires independent hydrogen production, hydrogen storage or hydrogen transmission equipment, long process flow and large equipment investment

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

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0025] (1) Catalyst 1% (wt) Pd / La-Al 2 o 3 preparation of

[0026] 1.59gLa(NO 3 ) 3 ·6H 2 O (purity 98%) is impregnated to 50g Al in equal volume 2 o 3 above, soaked overnight, dried at 100°C for 5h, and fired at 300°C for 5h to obtain La-Al 2 o 3 . 0.85gPdCl 2 (Purity is 98%) After dissolving with appropriate amount of water, impregnated into La-Al 2 o 3 After soaking for 2 hours, adjust the pH value of the solution to 9 with NaOH, continue stirring and soaking overnight, and then wash the solution with distilled water to neutrality. Then dry at 110°C for 5h, and bake at 300°C for 5h to get Pd / La-Al 2 o 3 catalyst.

[0027] (2) Pd / La-Al 2 o 3 Catalytic defluorination of 2,4,6-trifluoropyridine

[0028] Add 1% (wt) Pd / La-Al obtained in step (1) into a 300ml reactor 2 o 3 Catalyst 0.67g, using H 2 After replacing the air in the kettle for 3 times, the temperature was raised to 180 ° C, and the 2 The atmosphere was maintained for 2h. After the catalyst is d...

Embodiment 2

[0030] (1) Preparation of catalyst Pd / Ba-MgO

[0031] 2.86gBa(NO 3 ) 2 Equal volume was impregnated on 50g MgO, dried at 120°C for 3h after impregnated overnight, and baked at 500°C for 8h to obtain Ba-MgO. Then 7.50gPdCl 2 After dissolving, impregnate it on Ba-MgO, adjust the pH value of the solution to 9 with NaOH after impregnating for 3 hours, continue stirring and impregnating overnight, and then wash the solution with distilled water until neutral. Then dried at 120°C for 3h, and calcined at 500°C for 8h to obtain a Pd / La-MgO catalyst.

[0032] (2) Pd / Ba-MgO catalyzed debromination of 3,5-dibromopyridine

[0033] Add 0.3g of the prepared Pd / Ba-MgO catalyst in a 300ml reactor, raise the temperature to 100°C, and 2 The atmosphere was maintained for 1h. Add 115.9g (2.52mol) of ethanol, 80g of water and 1g (0.0042mol) of 3,5-dibromopyridine to the kettle after reducing the catalyst to gas, and stir and react at 60°C for 5 hours. The reaction solution is filtered and se...

Embodiment 3

[0035] (1) Catalyst 3% (wt) Pd / Ce-Al 2 o3 preparation of

[0036] 4.65gCe(NO 3 ) 3 ·6H 2 O equal volume impregnation to 50g Al 2 o 3 Above, soaked overnight, dried at 150°C for 5h, and calcined at 800°C for 10h to obtain Ce-Al 2 o 3 . Then 2.50gPdCl 2 Impregnation into Ce-Al after dissolution 2 o 3 After soaking for 6 hours, adjust the pH value of the solution to 10 with NaOH, continue stirring and soaking overnight, and then wash the solution with distilled water to neutrality. Then dry at 150°C for 6h, and bake at 800°C for 10h to get Pd / Ce-Al 2 o 3 catalyst.

[0037] (2) Pd / Ce-Al 2 o 3 Catalytic dechlorination of 2,4,6-trichloropyridine

[0038] Add the prepared 3% (wt) Pd / Ce-Al to the 300ml reactor 2 o 3 Catalyst 0.45g, utilize H 2 After replacing the air in the kettle for 3 times, the temperature was raised to 200°C, and the 2 The atmosphere was maintained for 8h. Add 160g (5mol) of isopropanol, 136.5g of water and 0.91g (0.005mol) of 2,4,6-trichlorop...

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 provides a dehalogenation degradation method for a halogenated pyridine compound. The halogenated pyridine compound is adopted as a raw material, alcohol is adopted as a hydrogen source, water is adopted as a solvent, reacting is carried out for 3-10 h under normal pressure at the temperature of 20 DEG C to 120 DEG C under the action of a supported catalyst, and the halogenated pyridine compound is subjected to dehalogenation degradation in situ through water phase hydrogen production. A pyridine ring of the halogenated pyridine compound at least contains an F or Cl or Br or I substituent group. The supported catalyst is composed of an active component and a carrier, the active component is composed of a mixture of transition metal and other metal, the transition metal is one of Rh, Pd, Pt and Ni, and other metal is one of Se, Ca, Ba, La and Ce. The carrier is one of activated carbon, kieselguhr, zeolite, gamma-Al2O3, AlF3 and MgO. H2 is not directly used as a reduction agent, activated hydrogen is prepared through in-situ catalysis to directly participate in reacting, the advantages of being high in reaction activity, high in selectivity, high in safety, environmentally friendly and the like are achieved, and good application prospects are achieved.

Description

technical field [0001] The invention relates to a dehalogenation degradation method of a halogenated pyridine compound, in particular to a dehalogenation degradation method of a halogenated pyridine compound with high reactivity, high selectivity and high safety. Background technique [0002] Halogenated pyridine compounds mainly include halogenated elements fluorine, chlorine, bromine, and iodine compounds, which are mainly used in pharmaceutical intermediates, pesticide intermediates, spices, dyes, surfactants, rubber additives, feed additives and other fields. Fluorine, heterocycle, and chirality are the three major characteristics of new drug synthesis in the field of modern pesticides. There are many types of fluorine-containing heterocyclic compounds. Due to the limitation of synthesis technology, pyridine fluorine-containing compounds are currently the most used. Pyridine fluorine-containing compounds have two characteristics of fluorine-containing and nitrogen-conta...

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
Patent Type & Authority Applications(China)
IPC IPC(8): C07D213/61B01J23/63B01J23/58
CPCC07D213/61B01J23/58B01J23/63
Inventor 谢建伟
Owner QUZHOU UNIV
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