Catalyst for synthesizing fluorine-containing halogenated hydrocarbons and preparation method thereof

Abstract

The invention discloses a catalyst for synthesizing fluorine-containing halogenated hydrocarbons and a preparation method thereof. The purpose of the method is to solve the problems of small specific surface area, non-adjustable pore size, expensive and complicated existing preparation methods in the preparation of the catalyst. In the catalyst of the present invention, the active component is composed of one or more elements of Group II, Group VIII, Cr or Cu; the metal fluoride active carrier is composed of one of aluminum fluoride, zirconium fluoride or magnesium fluoride one or more components. The preparation method of the large specific surface area of ​​the present invention, mesoporous structure metal fluoride-based catalyst comprises the following steps: (1) prepare the suspension liquid solution that contains large specific surface area, mesoporous structure metal oxide and organic polymer additive, at 0 Reflux at ~100°C, (2) Add the aqueous solution of the fluorinating reagent dropwise to the suspension obtained in (1) for fluorination; (3) Immerse the aqueous solution of the active component into the metal fluoride matrix obtained in (2) , and finally calcined at 350°C to 400°C to obtain the catalyst.

Description

technical field [0001] The invention belongs to the field of refrigerants and relates to a metal fluoride catalyst, in particular to a large specific surface area and mesoporous metal fluoride catalyst used for synthesizing fluorine-containing halogenated hydrocarbons and a mild and simple preparation method thereof. Background technique [0002] In the gas-phase catalytic synthesis of fluorine-containing halogenated hydrocarbons, such as the preparation of the third-generation refrigerant hydrofluorocarbons (HFCs) and the fourth-generation refrigerant hydrofluoroolefins (HFOs), strong corrosive HF or one of the reactants 1. It may be generated during the reaction, so the catalyst used must be a material that can exist stably in a high-temperature HF atmosphere. So far, metal fluorides are the only substances that can exist stably in the above-mentioned strong corrosive atmosphere for a long time. However, metal fluorides must have a large specific surface area to obtain con...

AI Technical Summary

Problems solved by technology

[0004] Above-mentioned report prepares the catalyzer that fluorine-containing halogenated hydrocarbon is used, still exists following problem at least: (1) anhydrous sol-gel fluorination method is that the organic solvent of metal source and anhydrous HF is fluorine with expensive organometallic source, and this method must be operated under anhydrous conditions, the process is complicated, and it is difficult to apply to industrial production. At the same time, the metal fluorides obtained are all amorphous structures, unstable at high temperatures, and will quickly crystallize into low specific surface area and inactive fluorides. (2) Although the raw materials of carbonation and fluorination are easy to get, the technological process is complicated, and high-temperature carbonization and carbon removal processes need to be carried out repeatedly, and the energy consumption is high, and its preparation method does not see the regulation and control of the metal fluoride pore structure, so it is difficult to obtain the pore High specific surface area metal fluorides whose size is concentrated in the mesoporous structure, and the temperature is greater than 350°C, and the catalyst is less than 50m 2 / g

Images