CN110902655A - Method and device for treating waste catalyst in difluoroethane production - Google Patents

Method and device for treating waste catalyst in difluoroethane production Download PDF

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Publication number
CN110902655A
CN110902655A CN201811089690.7A CN201811089690A CN110902655A CN 110902655 A CN110902655 A CN 110902655A CN 201811089690 A CN201811089690 A CN 201811089690A CN 110902655 A CN110902655 A CN 110902655A
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gas
tower
hydrogen fluoride
unit
washing
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CN201811089690.7A
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Chinese (zh)
Inventor
程明
曾本忠
宋琳
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Zhonghao Chenguang Research Institute of Chemical Industry Co Ltd
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Zhonghao Chenguang Research Institute of Chemical Industry Co Ltd
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    • CCHEMISTRY; METALLURGY
    • C01INORGANIC CHEMISTRY
    • C01BNON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B7/00Halogens; Halogen acids
    • C01B7/19Fluorine; Hydrogen fluoride
    • C01B7/191Hydrogen fluoride
    • CCHEMISTRY; METALLURGY
    • C01INORGANIC CHEMISTRY
    • C01BNON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B7/00Halogens; Halogen acids
    • C01B7/19Fluorine; Hydrogen fluoride
    • C01B7/191Hydrogen fluoride
    • C01B7/195Separation; Purification

Abstract

The invention relates to a method and a device for treating a waste catalyst in difluoroethane production. The processing method comprises the following steps: (1) carrying out high-temperature anaerobic pyrolysis on the waste catalyst, cooling the generated gas to be below 120 ℃, filtering and condensing to obtain liquid-phase hydrogen fluoride; discharging the uncondensed gas phase after washing; (2) further rectifying the liquid-phase hydrogen fluoride to obtain anhydrous hydrogen fluoride; (3) and continuously or intermittently discharging waste residues generated by the high-temperature oxygen-free pyrolysis. The treatment method is used for treating the waste catalyst in the production of difluoroethane and recovering the anhydrous hydrogen fluoride, can recover the anhydrous hydrogen fluoride to the maximum extent, reduces the discharge of waste water and thoroughly makes the waste catalyst harmless.

Description

Method and device for treating waste catalyst in difluoroethane production
Technical Field
The invention belongs to the field of organic fluorine environment-friendly treatment, and particularly relates to a method and a device for treating waste catalyst fluorosulfonic acid in difluoroethane production and recovering anhydrous hydrogen fluoride in the waste catalyst fluorosulfonic acid.
Background
In the production process of difluoroethane, the catalytic reaction is generally carried out by using fluorosulfonic acid as a catalyst. However, the catalyst has a short service life, and the activity of the catalyst is reduced along with the reaction, so that a new catalyst needs to be replaced every 2 to 4 days. The main components of the discharged waste catalyst are hydrogen fluoride, fluorosulfonic acid, sulfuric acid, and acetylene polymers, and hydrofluoric acid and sulfuric acid are strong acids, so that the waste catalyst has strong irritation and corrosive effects on eyes, skin, mucous membranes and respiratory tracts, and the pollution of the volatile acid gas to the environment is not negligible. Therefore, how to reasonably and effectively treat the waste catalyst, especially to recover a large amount of useful hydrogen fluoride, becomes one of the problems of various production enterprises at present.
Patent CN201406389Y discloses a device system for treating difluoroethane waste catalyst. The device comprises an evaporation kettle, a primary falling film absorption tower, a secondary washing absorption tower and an alkaline washing absorption tower which are sequentially connected in series, wherein the bottom of the evaporation kettle is connected with a waste residue pool. The waste catalyst is heated in an evaporation kettle to recover most hydrofluoric acid and then is put into a waste residue pool.
Although the method has a certain effect on recycling hydrofluoric acid, the recycled hydrogen fluoride is aqueous acid, the value is greatly reduced, the treated waste catalyst is still acidic in a waste residue pool, and the problem of waste water treatment also exists.
Disclosure of Invention
The invention provides a method and a device for thoroughly and harmlessly treating a waste catalyst and recovering anhydrous hydrogen fluoride in the waste catalyst aiming at the conditions of difficult treatment and environmental pollution of the waste catalyst in the production process of difluoroethane. The treatment method of the invention does not produce waste water, has high recovery rate of hydrogen fluoride, discharges a small amount of combustible organic matters after torch combustion, and avoids environmental pollution.
In order to achieve the above object, the present invention provides the following solutions:
a method for treating a waste catalyst in difluoroethane production comprises the following steps:
(1) carrying out high-temperature anaerobic pyrolysis on the waste catalyst, cooling the generated gas to be below 120 ℃, filtering and condensing to obtain liquid-phase hydrogen fluoride; discharging the uncondensed gas phase after washing;
(2) further rectifying the liquid-phase hydrogen fluoride to obtain anhydrous hydrogen fluoride;
(3) and continuously or intermittently discharging waste residues generated by the high-temperature oxygen-free pyrolysis.
Further, in the step (1), the main components of the waste catalyst are hydrogen fluoride, fluorosulfonic acid, sulfuric acid, acetylene polymer, and the like.
Further, in the step (1), the waste catalyst is subjected to high-temperature oxygen-free pyrolysis reaction in a liquid state, and the feeding flow rate is 20-500 kg/h; preferably 100 to 120 kg/h.
Further, in the step (1), the conditions of the high-temperature anaerobic pyrolysis are as follows: under normal pressure, the temperature is 200-500 ℃, preferably 350-450 ℃.
Further, in the step (1), the washing includes post-treatment such as water washing, alkali washing and the like.
Further, in the step (2), the rectification comprises primary degassing rectification and secondary recovery rectification; wherein the operation pressure of the tower top of the primary degassing and rectifying is 50-100 KPa, the non-condensable gas is removed from the tower top, and the hydrogen fluoride containing heavy components in the tower kettle is subjected to secondary rectification; and the operation pressure of the tower top of the secondary recovery rectification is-30 to 30KPa, the finished anhydrous hydrogen fluoride product is collected at the tower top, and the high-boiling-point substances in the tower kettle are discharged intermittently for treatment.
The invention also provides a treatment device of the waste catalyst in the production of difluoroethane, which comprises the following components: the high-temperature anhydrous pyrolysis unit, the cooling unit, the filtering unit, the condensing unit and the rectifying unit are sequentially connected; wherein, the gas discharge port of the condensing unit is connected with the washing unit and the combustion discharge unit in sequence.
Furthermore, the high-temperature oxygen-free pyrolysis unit can be a converter provided with a heat exchange jacket, and a filler made of metal materials, such as metal particles, Raschig rings, pall rings, intalox rings and the like made of metal materials such as carbon steel, stainless steel and the like, is arranged in the converter; the converter uses flue gas from coal or natural gas combustion as a heat source.
Further, the cooling unit is a chiller, preferably cooled with circulating water.
In the device, the cooling unit and the condensing unit can adopt different structural forms.
Further, the filtering unit adopts a wire mesh filter with a tangential inlet and cyclone separation function and is used for filtering smoke dust in the gas.
Further, the rectification unit comprises a degassing tower and a hydrogen fluoride recovery tower which are connected in sequence.
The treatment device of the invention is characterized in that the treatment device is connected in sequence, and also comprises instruments, pumps and other equipment commonly used in industrial production arranged between adjacent equipment.
Further, the washing unit includes a water washing tower, a caustic washing tower, which may adopt some structures that facilitate gas-liquid contact, and the like.
As one of the preferred embodiments of the present invention, the method for treating the spent catalyst in the production of difluoroethane comprises:
(1) introducing the waste catalyst liquid into a converter at a certain flow rate for high-temperature oxygen-free pyrolysis, wherein the converter contains metal particle fillers and is provided with a jacket, and introducing flue gas by adopting an induced draft fan to heat the converter;
(2) cooling the gas generated at the gas outlet of the converter in the step (1) by a quencher, cooling the cooled gas to below 120 ℃, and cooling by circulating water in the quencher;
(3) filtering the gas cooled in the step (2) to remove dust through a filter, wherein the filter can adopt a wire mesh filter;
(4) condensing the gas filtered in the step (3) to a storage tank through a condenser to form a liquid phase, discharging the uncondensed gas phase at the outlet of the condenser, discharging the gas to a water washing tower and an alkali washing tower, washing, discharging the gas to a torch, burning and emptying;
(5) the liquid phase condensed in the storage tank in the step (4) enters a degassing tower through a pump to be rectified and removed of light component gas;
(6) the liquid at the bottom of the degassing tower in the step (5) enters a hydrogen fluoride recovery tower for rectification, and anhydrous hydrogen fluoride is recovered at the tower top;
(7) the converter of the above (1) is one in which coked carbides are generated and which can be discharged continuously or intermittently.
The treatment method is used for treating the waste catalyst in the production of difluoroethane, can recover anhydrous hydrogen fluoride in the waste catalyst to the maximum extent, reduce the discharge of waste water and thoroughly eliminate the harm of the waste catalyst.
Drawings
FIG. 1 is a flow chart of the method for treating the spent catalyst in the difluoroethane production according to example 1 of the present invention.
In the figure: 1. a converter; 2. an induced draft fan; 3. a quencher; 4. a filter; 5. a condenser; 6. washing the tower with water; 7. an alkaline washing tower; 8. a torch; 9. a storage tank; 10. a delivery pump; 11. a degassing tower; 12. a hydrogen fluoride recovery tower.
Detailed Description
The following examples are intended to illustrate the invention but are not intended to limit the scope of the invention.
Embodiment 1 treatment device for waste catalyst in difluoroethane production
The embodiment provides a processing apparatus of useless catalyst in difluoroethane production, includes: a converter 1, a quencher 3, a filter 4, a condenser 5, a degassing tower 11 and a hydrogen fluoride recovery tower 12 which are connected in sequence; wherein, the gas discharge port of the condenser 5 is connected with a water scrubber 6, an alkali scrubber 7 and a torch 8 in sequence.
The converter 1 contains metal particle filler, the converter 1 is provided with a jacket, the converter 1 is heated by flue gas generated by burning coal or natural gas, and the flue gas subjected to heat exchange is discharged by an induced draft fan 2;
the chiller 3 is cooled using circulating water.
The filter 4 adopts a wire mesh filter with a cyclone separation function and enters tangentially, and is used for filtering smoke dust in gas.
A storage tank 9 is provided between the condenser 5 and the degassing tower 11 for temporarily storing the hydrogen fluoride condensed into a liquid phase. The liquid-phase hydrogen fluoride in the storage tank 9 is fed into a degassing column 11 by a feed pump 10.
Example 2 method for treating spent catalyst in difluoroethane production
The embodiment provides a method for treating a waste catalyst in difluoroethane production, as shown in fig. 1, comprising the following steps:
(1) introducing waste catalyst liquid (mainly containing polymers of hydrogen fluoride, fluorosulfonic acid, sulfuric acid and acetylene) discharged in the production of difluoroethane into a converter at a flow rate of 100-120 kg/h for high-temperature oxygen-free pyrolysis, wherein the converter contains metal particle fillers and is provided with a jacket, heating the converter by using flue gas generated by burning coal or natural gas, and discharging the flue gas subjected to heat exchange through an induced draft fan;
wherein, the conditions of the high-temperature anaerobic pyrolysis are as follows: the temperature is 400 ℃, the retention time is 2h, and the pressure is normal pressure;
(2) cooling the gas generated at the gas outlet of the converter in the step (1) in a quencher, cooling the cooled gas to 120 ℃, and cooling the gas in the quencher by using circulating hot water;
(3) filtering the cooled gas in the step (2) to remove dust through a filter; the filter enters a wire mesh filter with a cyclone separation function tangentially;
(4) and (4) condensing the gas filtered in the step (3) in a condenser through a refrigerant, condensing most hydrogen fluoride into a liquid phase and storing the liquid phase in a storage tank, discharging the uncondensed gas to a water scrubber for absorbing with water, then discharging the gas into a torch for combustion after the gas is contacted and neutralized with circulating alkali liquor through an alkali scrubber, and then discharging the gas for emptying.
(5) The liquid phase crude hydrogen fluoride collected in the storage tank ⑨ is conveyed to a degassing tower through a conveying pump for rectification, light component gas is collected from the tower top and discharged to a water washing tower, and finally enters a torch through an alkali washing tower for combustion and then is discharged, wherein the degassing tower has the tower top operating pressure of 80KPa, and noncondensable gas is removed from the tower top.
(6) The liquid in the tower kettle of the degassing tower enters a hydrogen fluoride recovery tower for rectification, qualified hydrogen fluoride is recovered from the tower top of the hydrogen fluoride recovery tower and can be used as a raw material for synthesizing difluoroethane, and the residual liquid in the tower kettle of the hydrogen fluoride recovery tower is intermittently extracted and treated as waste. The operation pressure of the top of the hydrogen fluoride recovery tower is 0 kPa.
(7) The waste catalyst in the converter in the step (1) is subjected to anaerobic pyrolysis, and then granular carbide is generated and can be continuously or intermittently discharged along with the metal filler.
Although the invention has been described in detail hereinabove with respect to a general description and specific embodiments thereof, it will be apparent to those skilled in the art that modifications or improvements may be made thereto based on the invention. Accordingly, such modifications and improvements are intended to be within the scope of the invention as claimed.

Claims (9)

1. A method for treating a waste catalyst in difluoroethane production is characterized by comprising the following steps:
(1) carrying out high-temperature anaerobic pyrolysis on the waste catalyst, cooling the generated gas to be below 120 ℃, filtering and condensing to obtain liquid-phase hydrogen fluoride; discharging the uncondensed gas phase after washing;
(2) further rectifying the liquid-phase hydrogen fluoride to obtain anhydrous hydrogen fluoride;
(3) and continuously or intermittently discharging waste residues generated by the high-temperature oxygen-free pyrolysis.
2. The process according to claim 1, wherein in the step (1), the spent catalyst is subjected to high-temperature anaerobic pyrolysis reaction in a liquid form, and the feeding flow rate is 20-500 kg/h; preferably 100 to 120 kg/h.
3. The process according to claim 1 or 2, characterized in that in step (1), the conditions of high-temperature anaerobic pyrolysis are: under normal pressure, the temperature is 200-500 ℃, preferably 350-450 ℃.
4. A method according to any one of claims 1 to 3, wherein in step (1), the washing comprises water washing and/or alkali washing.
5. The process according to any one of claims 1 to 4, wherein in step (2), the rectification comprises a first degassing rectification and a second recovery rectification;
preferably, the operation pressure of the tower top of the primary degassing and rectifying is 50-100 KPa, the non-condensable gas is removed from the tower top, and the hydrogen fluoride containing heavy components in the tower kettle is subjected to secondary rectification;
and/or the presence of a gas in the gas,
preferably, the operation pressure of the top of the secondary recovery rectification tower is-30 to 30KPa, the finished anhydrous hydrogen fluoride product is collected at the top of the tower, and the high-boiling-point substances in the tower kettle are intermittently discharged and treated.
6. The processing method according to claim 1, comprising:
(1) introducing the waste catalyst liquid into a converter at a certain flow rate for high-temperature oxygen-free pyrolysis, wherein the converter contains metal particle fillers and is provided with a jacket, and introducing flue gas by adopting an induced draft fan to heat the converter;
(2) cooling the gas generated at the gas outlet of the converter in the step (1) by a cooler, and reducing the temperature of the cooled gas to below 120 ℃;
(3) filtering the cooled gas in the step (2) to remove dust through a filter;
(4) condensing the gas filtered in the step (3) to a storage tank through a condenser to form a liquid phase, discharging the uncondensed gas phase at the outlet of the condenser, discharging the gas to a water washing tower and an alkali washing tower, washing, discharging the gas to a torch, burning and emptying;
(5) the liquid phase condensed in the storage tank in the step (4) enters a degassing tower through a pump to be rectified and removed of light component gas;
(6) the liquid at the bottom of the degassing tower in the step (5) enters a hydrogen fluoride recovery tower for rectification, and anhydrous hydrogen fluoride is recovered at the tower top;
(7) the coke and carbide are produced in the converter (1) and are continuously or intermittently discharged.
7. A processing apparatus of useless catalyst in difluoroethane production, characterized by includes: the high-temperature anhydrous pyrolysis unit, the cooling unit, the filtering unit, the condensing unit and the rectifying unit are sequentially connected; wherein, the gas discharge port of the condensing unit is connected with the washing unit and the combustion discharge unit in sequence.
8. The processing unit according to claim 7, wherein the high temperature oxygen-free pyrolysis unit is a converter with a heat exchange jacket inside, and flue gas from coal or natural gas combustion is used as a heat source;
and/or a metal material filler is arranged in the high-temperature oxygen-free pyrolysis unit.
9. The processing apparatus according to claim 7 or 8, wherein the filter unit employs a tangential entry wire mesh filter with cyclone separation;
and/or the rectifying unit comprises a degassing tower and a hydrogen fluoride recovery tower which are connected in sequence;
and/or the washing unit comprises a water washing tower and a caustic washing tower.
CN201811089690.7A 2018-09-18 2018-09-18 Method and device for treating waste catalyst in difluoroethane production Pending CN110902655A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110906335A (en) * 2018-09-18 2020-03-24 中昊晨光化工研究院有限公司 Method and device for treating waste catalyst in difluoroethane production

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2547838A1 (en) * 1974-12-30 1976-07-08 Texaco Development Corp Regenerating spent alkylation catalyst - contg fluorosulphonic acid and sulphuric acid used for branched paraffin prodn
CN1962064A (en) * 2006-11-29 2007-05-16 山东东岳高分子材料有限公司 Method for processing waste catalyst in production of pentafluoro ethane
CN101417924A (en) * 2008-12-09 2009-04-29 常熟三爱富中昊化工新材料有限公司 Method for separating fluorine hydride from 1,1-difluoroethane production
CN201406389Y (en) * 2009-04-29 2010-02-17 山东华安新材料有限公司 Difluoroethane waste catalyst treatment device system
CN102661654A (en) * 2012-05-02 2012-09-12 北京华宇同方化工科技开发有限公司 Method and system for preparing high purity gas by rectification method
CN105314599A (en) * 2015-11-17 2016-02-10 龚兴荣 Method for producing anhydrous hydrogen fluoride and white carbon black through fluosilicic acid
CN205784519U (en) * 2016-05-19 2016-12-07 湖南万容科技股份有限公司 A kind of internal heat type Non-oxygen pyrolytic rotary kiln device

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2547838A1 (en) * 1974-12-30 1976-07-08 Texaco Development Corp Regenerating spent alkylation catalyst - contg fluorosulphonic acid and sulphuric acid used for branched paraffin prodn
CN1962064A (en) * 2006-11-29 2007-05-16 山东东岳高分子材料有限公司 Method for processing waste catalyst in production of pentafluoro ethane
CN101417924A (en) * 2008-12-09 2009-04-29 常熟三爱富中昊化工新材料有限公司 Method for separating fluorine hydride from 1,1-difluoroethane production
CN201406389Y (en) * 2009-04-29 2010-02-17 山东华安新材料有限公司 Difluoroethane waste catalyst treatment device system
CN102661654A (en) * 2012-05-02 2012-09-12 北京华宇同方化工科技开发有限公司 Method and system for preparing high purity gas by rectification method
CN105314599A (en) * 2015-11-17 2016-02-10 龚兴荣 Method for producing anhydrous hydrogen fluoride and white carbon black through fluosilicic acid
CN205784519U (en) * 2016-05-19 2016-12-07 湖南万容科技股份有限公司 A kind of internal heat type Non-oxygen pyrolytic rotary kiln device

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110906335A (en) * 2018-09-18 2020-03-24 中昊晨光化工研究院有限公司 Method and device for treating waste catalyst in difluoroethane production

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Application publication date: 20200324