CN113563153A - Method for preparing monochloro-o-xylene by continuous chlorination of o-xylene - Google Patents
Method for preparing monochloro-o-xylene by continuous chlorination of o-xylene Download PDFInfo
- Publication number
- CN113563153A CN113563153A CN202110981321.4A CN202110981321A CN113563153A CN 113563153 A CN113563153 A CN 113563153A CN 202110981321 A CN202110981321 A CN 202110981321A CN 113563153 A CN113563153 A CN 113563153A
- Authority
- CN
- China
- Prior art keywords
- reactor
- chlorination
- combined
- tower
- kettle
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 238000005660 chlorination reaction Methods 0.000 title claims abstract description 216
- CTQNGGLPUBDAKN-UHFFFAOYSA-N O-Xylene Chemical group CC1=CC=CC=C1C CTQNGGLPUBDAKN-UHFFFAOYSA-N 0.000 title claims abstract description 161
- 229940078552 o-xylene Drugs 0.000 title claims abstract description 62
- 238000000034 method Methods 0.000 title claims abstract description 44
- NVLHGZIXTRYOKT-UHFFFAOYSA-N 1-chloro-2,3-dimethylbenzene Chemical group CC1=CC=CC(Cl)=C1C NVLHGZIXTRYOKT-UHFFFAOYSA-N 0.000 title claims abstract description 17
- 238000006243 chemical reaction Methods 0.000 claims abstract description 82
- 239000000460 chlorine Substances 0.000 claims abstract description 82
- 229910052801 chlorine Inorganic materials 0.000 claims abstract description 82
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 claims abstract description 81
- 238000007872 degassing Methods 0.000 claims abstract description 30
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 claims abstract description 24
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 claims abstract description 24
- 239000002841 Lewis acid Substances 0.000 claims abstract description 15
- 150000007517 lewis acids Chemical class 0.000 claims abstract description 15
- 238000003860 storage Methods 0.000 claims abstract description 11
- 239000000376 reactant Substances 0.000 claims abstract description 10
- 238000003756 stirring Methods 0.000 claims abstract description 6
- 239000007795 chemical reaction product Substances 0.000 claims abstract description 5
- 239000000463 material Substances 0.000 claims description 119
- KZBUYRJDOAKODT-UHFFFAOYSA-N Chlorine Chemical compound ClCl KZBUYRJDOAKODT-UHFFFAOYSA-N 0.000 claims description 30
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 22
- VSCWAEJMTAWNJL-UHFFFAOYSA-K aluminium trichloride Chemical compound Cl[Al](Cl)Cl VSCWAEJMTAWNJL-UHFFFAOYSA-K 0.000 claims description 11
- 238000001816 cooling Methods 0.000 claims description 9
- RBTARNINKXHZNM-UHFFFAOYSA-K iron trichloride Chemical compound Cl[Fe](Cl)Cl RBTARNINKXHZNM-UHFFFAOYSA-K 0.000 claims description 7
- DAMJCWMGELCIMI-UHFFFAOYSA-N benzyl n-(2-oxopyrrolidin-3-yl)carbamate Chemical compound C=1C=CC=CC=1COC(=O)NC1CCNC1=O DAMJCWMGELCIMI-UHFFFAOYSA-N 0.000 claims description 5
- 230000007797 corrosion Effects 0.000 claims description 4
- 238000005260 corrosion Methods 0.000 claims description 4
- 239000007769 metal material Substances 0.000 claims description 3
- HPGGPRDJHPYFRM-UHFFFAOYSA-J tin(iv) chloride Chemical compound Cl[Sn](Cl)(Cl)Cl HPGGPRDJHPYFRM-UHFFFAOYSA-J 0.000 claims description 3
- 239000000956 alloy Substances 0.000 claims 1
- 229910001092 metal group alloy Inorganic materials 0.000 claims 1
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 20
- 239000007789 gas Substances 0.000 description 14
- 229910000041 hydrogen chloride Inorganic materials 0.000 description 14
- IXCSERBJSXMMFS-UHFFFAOYSA-N hydrogen chloride Substances Cl.Cl IXCSERBJSXMMFS-UHFFFAOYSA-N 0.000 description 14
- 238000000605 extraction Methods 0.000 description 11
- 239000000203 mixture Substances 0.000 description 11
- 229910052757 nitrogen Inorganic materials 0.000 description 10
- 239000003054 catalyst Substances 0.000 description 7
- 238000007599 discharging Methods 0.000 description 7
- 238000010907 mechanical stirring Methods 0.000 description 7
- 239000002245 particle Substances 0.000 description 7
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical group [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 6
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 description 6
- 238000010521 absorption reaction Methods 0.000 description 6
- 239000007788 liquid Substances 0.000 description 6
- 238000004519 manufacturing process Methods 0.000 description 6
- 239000006096 absorbing agent Substances 0.000 description 5
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 5
- MVPPADPHJFYWMZ-UHFFFAOYSA-N chlorobenzene Chemical compound ClC1=CC=CC=C1 MVPPADPHJFYWMZ-UHFFFAOYSA-N 0.000 description 5
- 239000002994 raw material Substances 0.000 description 5
- 239000000919 ceramic Substances 0.000 description 4
- 239000000498 cooling water Substances 0.000 description 4
- 239000011521 glass Substances 0.000 description 4
- 239000001257 hydrogen Substances 0.000 description 4
- 229910052739 hydrogen Inorganic materials 0.000 description 4
- 239000001301 oxygen Substances 0.000 description 4
- 229910052760 oxygen Inorganic materials 0.000 description 4
- 238000012856 packing Methods 0.000 description 4
- 239000011148 porous material Substances 0.000 description 4
- UHOVQNZJYSORNB-UHFFFAOYSA-N Benzene Chemical compound C1=CC=CC=C1 UHOVQNZJYSORNB-UHFFFAOYSA-N 0.000 description 3
- 239000004642 Polyimide Substances 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- QWPPOHNGKGFGJK-UHFFFAOYSA-N hypochlorous acid Chemical compound ClO QWPPOHNGKGFGJK-UHFFFAOYSA-N 0.000 description 3
- 229920001721 polyimide Polymers 0.000 description 3
- 238000005070 sampling Methods 0.000 description 3
- 238000012546 transfer Methods 0.000 description 3
- UERPUZBSSSAZJE-UHFFFAOYSA-N 3-chlorophthalic anhydride Chemical compound ClC1=CC=CC2=C1C(=O)OC2=O UERPUZBSSSAZJE-UHFFFAOYSA-N 0.000 description 2
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 2
- 229910021627 Tin(IV) chloride Inorganic materials 0.000 description 2
- GTDPSWPPOUPBNX-UHFFFAOYSA-N ac1mqpva Chemical compound CC12C(=O)OC(=O)C1(C)C1(C)C2(C)C(=O)OC1=O GTDPSWPPOUPBNX-UHFFFAOYSA-N 0.000 description 2
- 239000003513 alkali Substances 0.000 description 2
- 238000003763 carbonization Methods 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 238000010924 continuous production Methods 0.000 description 2
- -1 enamel Substances 0.000 description 2
- 239000011552 falling film Substances 0.000 description 2
- 229910052742 iron Inorganic materials 0.000 description 2
- 239000011344 liquid material Substances 0.000 description 2
- 239000000178 monomer Substances 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- DFOZLRWOCDRNDA-UHFFFAOYSA-N 4,5-dichloroisoindole-1,3-dione Chemical compound ClC1=CC=C2C(=O)NC(=O)C2=C1Cl DFOZLRWOCDRNDA-UHFFFAOYSA-N 0.000 description 1
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 description 1
- 229910021577 Iron(II) chloride Inorganic materials 0.000 description 1
- 229910021578 Iron(III) chloride Inorganic materials 0.000 description 1
- 229910001069 Ti alloy Inorganic materials 0.000 description 1
- 229910001093 Zr alloy Inorganic materials 0.000 description 1
- 125000003118 aryl group Chemical group 0.000 description 1
- KCXMKQUNVWSEMD-UHFFFAOYSA-N benzyl chloride Chemical compound ClCC1=CC=CC=C1 KCXMKQUNVWSEMD-UHFFFAOYSA-N 0.000 description 1
- IISBACLAFKSPIT-UHFFFAOYSA-N bisphenol A Chemical class C=1C=C(O)C=CC=1C(C)(C)C1=CC=C(O)C=C1 IISBACLAFKSPIT-UHFFFAOYSA-N 0.000 description 1
- 239000006227 byproduct Substances 0.000 description 1
- 238000003889 chemical engineering Methods 0.000 description 1
- 238000012824 chemical production Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 210000003298 dental enamel Anatomy 0.000 description 1
- 238000005474 detonation Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000004821 distillation Methods 0.000 description 1
- 238000004880 explosion Methods 0.000 description 1
- 239000002360 explosive Substances 0.000 description 1
- 239000003546 flue gas Substances 0.000 description 1
- 229910000856 hastalloy Inorganic materials 0.000 description 1
- 150000002431 hydrogen Chemical class 0.000 description 1
- 238000009776 industrial production Methods 0.000 description 1
- PNDPGZBMCMUPRI-UHFFFAOYSA-N iodine Chemical compound II PNDPGZBMCMUPRI-UHFFFAOYSA-N 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000013021 overheating Methods 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 229920001343 polytetrafluoroethylene Polymers 0.000 description 1
- 239000004810 polytetrafluoroethylene Substances 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 230000036632 reaction speed Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 230000000087 stabilizing effect Effects 0.000 description 1
- 230000002194 synthesizing effect Effects 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
- 239000002351 wastewater Substances 0.000 description 1
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C17/00—Preparation of halogenated hydrocarbons
- C07C17/093—Preparation of halogenated hydrocarbons by replacement by halogens
- C07C17/10—Preparation of halogenated hydrocarbons by replacement by halogens of hydrogen atoms
- C07C17/12—Preparation of halogenated hydrocarbons by replacement by halogens of hydrogen atoms in the ring of aromatic compounds
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention discloses a method for preparing monochloro-o-xylene by continuous chlorination of o-xylene, which comprises the following steps: (1) adding the dried o-xylene and the Lewis acid into a batching kettle in proportion, and uniformly stirring; (2) introducing reactants in the batching kettle into the tower kettle combined chlorination reactor through a reaction tower in the tower kettle combined reactor, introducing dried chlorine into the tower kettle combined chlorination reactor, and controlling the ratio of o-xylene to chlorine so as to carry out continuous chlorination reaction; (3) and (3) conveying the reaction product chloride of the tower kettle combined chlorination reactor into a degassing tower, removing HCl and residual chlorine in the degassing tower, and conveying the chloride into a chloride storage tank. The method combines the kettle reactor and the tower reactor, and can realize the purpose of safely and efficiently producing the chloro-o-xylene.
Description
Technical Field
The disclosure relates to the field of chemical production processes, and in particular relates to a method for preparing monochloro-o-xylene through continuous chlorination of o-xylene.
Background
In recent years, with the rapid development of the polyimide industry, the dianhydride monomer is increasingly required. The monochlorophthalic anhydride prepared by oxidizing monochloro-o-xylene is an ideal raw material for synthesizing a plurality of dianhydride monomers, and even polyimide can be directly synthesized by bischlorophthalimide and bisphenol salt, so that the production cost of the polyimide is greatly reduced. There is currently little research on monochloro-o-xylene and only patent CN1080278A discloses an example of batch chlorination in a tank reactor. Similar to the o-xylene chlorination process, the chlorination of benzene to chlorobenzene and the chlorination of toluene to monochlorobenzene are carried out, and two common industrial production schemes are adopted:
one is an intermittent chlorination process of a kettle reactor, which is very similar to o-xylene disclosed in patent CN1080278A, and has the same problems of low production efficiency, low chlorine utilization rate (less than 90 percent and only 82 percent of the rate), and large material holding capacity of reaction equipment;
a continuous chlorination process using tower-type reactor features that a large number of iron rings are installed in a reaction tower without adding catalyst, and the water content in toluene is used to generate FeCl3And (4) preparing a catalyst. Although the scheme realizes continuous production, the potential safety hazard is large, and the scheme is embodied in the following aspects: firstly, the chlorine reacts with water to generate hypochlorous acid in the process of generating hydrochloric acid, and the hypochlorous acid generates atomic oxygen or oxygen with higher activity when being heated; on the other hand, hydrochloric acid reacts with an iron ring to generate FeCl2Hydrogen gas is simultaneously generated. Therefore, chlorine, hydrogen, oxygen and explosive raw materials exist in the reaction system at the same time, and safety risk is brought to production. The reason for the frequent occurrence of detonations in the absorption of off-gases in the production of chlorobenzene and chlorotoluene is that the chlorination of aromatics, which is originally safer, is in this case more dangerous. Some chlorination safety accidents are also caused by the reaction explosion of chlorine, hydrogen and oxygen. In addition, the tower reactor has poor heat transfer due to no stirring, and is easy to generate the condition of material carbonization caused by local overheating, which is called as black material in the industry. Office of this kindOverheating also carries a safety risk.
The monochloro-o-xylene and air oxidation are relatively feasible methods for industrially producing monochloro-phthalic anhydride, but the literature for preparing the monochloro-o-xylene by taking o-xylene as a raw material is very few. Patent CN1080278A discloses a method for obtaining monochloro-o-xylene by directly chlorinating chlorine gas in a stirred reactor with o-xylene as raw material and lewis acid such as ferric trichloride, aluminum trichloride, antimony trichloride, stannic chloride, etc. or iodine, iron, etc. as catalyst. This method exposes the following disadvantages in industrial practice:
(1) because the heat exchange area of the chlorination kettle jacket is limited, the reaction heat transfer is not timely, the temperature of the system is increased, and polychlorinated substitutes are easy to generate.
(2) The contact time of chlorine gas introduced into the bottom of the chlorination kettle and o-xylene is too short, so that the reaction is insufficient, and a part of chlorine gas escapes, so that the raw material loss is caused, and the trouble of tail gas aftertreatment, even pollution, is caused.
(3) The chlorination reaction is a dangerous process, the kettle type chlorination reaction can only adopt a batch reaction, and under the condition of the same productivity, compared with a continuous reaction device, the batch device has larger instantaneous material holding amount, so that in case of accidents, the more serious harm is caused.
(4) The intermittent reaction process device is relatively troublesome to automatically control, has more production operators and does not meet the requirement of safety management of modern chemical engineering.
Disclosure of Invention
In order to solve the problems, the present disclosure provides a method for preparing monochloro-o-xylene by continuous chlorination of o-xylene, comprising:
(1) adding the dried o-xylene and the Lewis acid into a batching kettle in proportion, and uniformly stirring;
(2) adding the materials in the batching kettle into the combined chlorination reactor at the tower kettle from the upper part of the reaction tower, introducing dried chlorine into the combined chlorination reactor at the tower kettle, and controlling the ratio of o-xylene to chlorine so as to carry out continuous chlorination reaction;
(3) and (3) conveying the reaction product chloride of the tower kettle combined chlorination reactor into a degassing tower, removing HCl and residual chlorine in the degassing tower, and conveying the chloride into a chloride storage tank.
In a preferred embodiment, the chlorination reaction temperature is controlled between 0 ℃ and 80 ℃ to obtain the chloride.
In a preferred embodiment, the exothermic heat of the chlorination reaction is removed by a column kettle combined with circulating water of a jacket outside the chlorination reactor and a cooler outside the kettle, so as to better control the temperature of the chlorination reaction and ensure the safety of a chlorination reaction system.
In a preferred embodiment, the purity of both ortho-xylene and chlorine is greater than 99.5% and the water content is less than 400ppm, preferably less than 100 ppm.
In a preferred embodiment, in the step (2), the combined column-bottom reactor comprises a reaction column directly installed on the combined column-bottom chlorination reactor, and the combined column-bottom chlorination reactor and the reaction column are connected to the combined column-bottom chlorination reactor through pipelines.
In a preferred embodiment, the material of the combined reactor in the tower bottom comprises a metal lining corrosion-resistant non-metallic material, such as enamel, polytetrafluoroethylene and the like; also included are corrosion resistant metallic materials such as titanium alloys, zirconium alloys, hastelloy, and the like.
In a preferred embodiment, in step (2), the column bottom combined reactor comprises a single stage and a plurality of stages. The single-stage chlorination can also realize continuous chlorination operation, and the effect is better by adopting multi-stage series operation. In a preferred embodiment, in step (2), the combined column-bottom reactor may comprise a first-stage combined column-bottom reactor and a second-stage combined column-bottom reactor. In a preferred embodiment, the structural form of the reaction tower of the combined column-bottom reactor comprises a packed tower, a sieve plate tower and a bubble column.
In a preferred embodiment, the reaction columns of the multi-stage column-bottom combined reactor can be optionally combined by various structural forms.
In a preferred embodiment, the chlorination reaction temperature in the single-stage column-bottom combined reactor is controlled to be 0-80 ℃.
In a preferred embodiment, the chlorination reaction temperature of each stage of the tower kettle combined reactor in the multi-stage tower kettle combined reactor is controlled to be 0-80 ℃; preferably, the chlorination reaction temperature of each stage of the tower-still combined reactor can be optionally selected within the range of 0-80 ℃, for example, the preferable range can be selected according to actual situations such as: 0-40 deg.C, 5-40 deg.C, 10-25 deg.C, 30-40 deg.C, 30-70 deg.C, etc.
In a preferred embodiment, in the step (2), the dried chlorine gas is bubbled into the liquid material which is introduced into the combined chlorination reactor through a gas distributor at the lower part of the combined chlorination reactor in the tower kettle, and the gas generated in the chlorination reaction is captured by a reaction tower and a condenser at the upper part of the combined chlorination reactor in the tower kettle and then enters the HCl absorption process. The reacted materials are continuously extracted by a circulating pump below the tower kettle combined chlorination reactor and directly enter a degassing tower in a single-stage tower kettle combined reactor device; in the multi-stage series-connected tower kettle combined reactor device, the materials enter the next-stage tower kettle combined reactor through the top of the next-stage reaction tower, and the extracted materials of the last-stage tower kettle combined reactor are sent into a degassing tower by a circulating pump. After the continuous chlorination is started, a part of materials are circulated between the tower kettle combined chlorination reactor and the reaction tower through the circulating pump, and react with chlorine escaped from the tower kettle combined chlorination reactor together with the materials added from the top of the tower, so that the chlorine is fully utilized.
In a preferred embodiment, in the step (2), the tower-still combination reactor comprises a first-stage tower-still combination reactor, a second-stage tower-still combination reactor and a third-stage tower-still combination reactor.
In a preferred embodiment, a four-stage column-bottom combined reactor can be optionally included in step (2).
In a preferred embodiment, in step (2), the molar ratio of ortho-xylene: chlorine is introduced at the mol ratio of 1: 0.3-0.8.
In a preferred embodiment, in a first-stage column-bottom combined reactor, the molar ratio of ortho-xylene: introducing chlorine gas with the mol ratio of the chlorine gas of 1:0.5-0.8, and controlling the chlorination reaction temperature to be 30-70 ℃. Preferably, the chlorination reaction temperature is controlled to be 30-40 ℃ in the first-stage tower-kettle combined reactor.
In a two-stage tower-kettle combined reactor, the reaction ratio of o-xylene: introducing chlorine gas with the mol ratio of the chlorine gas of 1:0.4-0.6, and controlling the chlorination reaction temperature to be 5-40 ℃. Preferably, the chlorination reaction temperature is controlled to be 30-35 ℃ in the second-stage tower-kettle combined reactor.
In a three-stage tower-kettle combined reactor, the reaction conditions are as follows: introducing chlorine gas with the mol ratio of 1:0.3-0.5, and controlling the chlorination reaction temperature to be 0-40 ℃. Preferably, the chlorination reaction temperature is controlled to be 10-25 ℃ in the three-stage tower-kettle combined reactor.
In a preferred embodiment, in step (1), the molar ratio of o-xylene to Lewis acid is 100:0.01 to 1. Preferably, the molar ratio of ortho-xylene to lewis acid is from 100:0.1 to 0.5.
In a preferred embodiment, the lewis acid is selected from one or a mixture of iron trichloride, aluminum trichloride, antimony trichloride and stannic chloride.
In a preferred embodiment, the method further comprises:
and cooling the chloride which is the reaction product of the tower kettle combined chlorination reactor before the chloride is sent to a degassing tower.
In a preferred embodiment, the method further comprises:
and the degassing tower is used for removing hydrogen chloride gas and a small amount of chlorine gas in the materials.
In a preferred embodiment, the degasser is a continuous degasser. Preferably, the continuous degassing column is a packed column.
In a preferred embodiment, the method further comprises:
the tail gas generated by the tower kettle combined chlorination reactor and the tail gas or flue gas of the degassing tower are converged and then enter an HCl absorber, a falling film absorber or other absorbers can be adopted for converting hydrogen chloride gas into hydrochloric acid, and the absorbed tail gas enters an alkaline tower for washing and purifying and then is discharged.
The method combines the kettle reactor and the tower reactor, exerts the advantages of the kettle reactor and the tower reactor, overcomes the defects of the kettle reactor and the tower reactor, and can realize the purpose of safely and efficiently producing the chloro-o-xylene.
The advancement of the disclosure has the following aspects:
1. the continuous chlorination reaction is realized by combining the reaction tower and the chlorination reactor in a form of a tower and kettle combined reactor, and the reactor has the advantages of high efficiency, less material holding amount of a unit capacity reactor and good safety compared with a single kettle reactor.
2. The material added from the top of the reaction tower and the material circulated by the circulating pump can react with the chlorine escaped from the combined chlorination reactor at the bottom of the tower in the reaction tower, thereby effectively capturing and utilizing the chlorine, not only reducing the cost, but also greatly improving the safety of chlorination.
3. The o-xylene and the liquid chlorine are dried to reduce hypochlorous acid generated by the reaction of the chlorine and the water so as to generate oxygen, and the catalyst is directly added; instead of the catalyst synthesized by the reaction of the moisture in the materials, chlorine and metallic iron which is commonly adopted in aromatic chlorination in the industry at present, the generation of hydrogen is avoided, and the safety of a reaction system is improved.
4. For deacidification of chloride generated by chlorination reaction, the invention adopts a degassing tower with higher efficiency, nitrogen is used for removing residual hydrogen chloride gas in the chloride, the hydrogen chloride gas and the hydrogen chloride gas generated by the chlorination reaction enter a hydrogen chloride absorber to be converted into hydrochloric acid, a falling film absorber can be used for absorbing HCl, and residual tail gas is neutralized by an alkaline tower, so that not only can continuous production be conveniently realized, the number of workers in a workshop is reduced, but also waste utilization can be realized, and a large amount of waste water which is difficult to treat is reduced.
5. The invention adds the external circulation heat exchanger, so that the reaction heat can be transferred through two channels, namely the circulating water of the external jacket of the tower-kettle combined chlorination reactor and the cooler outside the kettle, the temperature control is more accurate and convenient, the invention has important significance for reducing the generation of polychlorinated o-xylene, and the invention can avoid the occurrence of material carbonization caused by overhigh local temperature rise caused by poor heat transfer of a single tower reactor and the safety risk caused by the situation.
6. The o-xylene chlorination reaction is realized by single-stage and/or multi-stage tower kettle combined reactors, and the multi-chlorine substitute is controlled to generate better effect by controlling different material molar ratios and temperatures of the reactors for the multi-stage tower kettle combined reactors connected in series.
The catalyst for the chlorination of o-xylene is Lewis acid, wherein the weight ratio of o-xylene: the molar ratio of the Lewis acid is 100: 0.01-1.
7. The reaction temperature of the o-xylene chlorination is 0-80 ℃.
Drawings
The accompanying drawings, which are included to provide a further understanding of the disclosure and are incorporated in and constitute a part of this specification, illustrate exemplary embodiments of the disclosure and together with the description serve to explain the principles of the disclosure.
FIG. 1 is a process flow diagram illustrating the continuous chlorination process for the preparation of monochloro-ortho-xylene according to the present disclosure.
Reference numerals:
1: a batching kettle; 2: a chlorine pressure stabilizing tank; 3: a first-stage tower kettle is combined with a chlorination reactor; 4: a second-stage tower kettle is combined with a chlorination reactor; 5: a third-stage tower kettle is combined with a chlorination reactor; 6. 7, 8: a reaction tower; 9. 10, 11: a cooler; 12. 13, 14, 19: a condenser; 15. 16, 17, 20: a condensate collection tank; 18: a degassing tower.
Detailed Description
The present disclosure will be described in further detail with reference to the drawings and embodiments. It is to be understood that the specific embodiments described herein are for purposes of illustration only and are not to be construed as limitations of the present disclosure. It should be further noted that, for the convenience of description, only the portions relevant to the present disclosure are shown in the drawings.
It should be noted that the embodiments and features of the embodiments in the present disclosure may be combined with each other without conflict. The present disclosure will be described in detail below with reference to the accompanying drawings in conjunction with embodiments.
The application discloses a method for continuously producing chloro-ortho-xylene, wherein the purity of ortho-xylene and chlorine is more than 99.5%, and the water content is less than 400ppm, preferably less than 100 ppm.
O-xylene: the Lewis acid is 100: 0.01-1, and preferably the Lewis acid is o-xylene: the Lewis acid is 100: 0.1-0.5.
The application discloses a method for continuously producing chloro-o-xylene. The three-stage column reactor combined chlorination reactor is exemplified below.
1.1, preparing materials: the ortho-xylene and catalyst are mixed as follows: adding Lewis acid into the batching kettle 1 in a ratio of 100: 0.01-1, and uniformly stirring;
1.2 initial charge: and (3) starting cooling water of the condensate collecting tank 15, adding the mixed material into the first-stage tower-kettle combined chlorination reactor 3 from the batching kettle 1 through the reaction tower 6, stopping feeding when the liquid level reaches 30%, starting feeding the first-stage tower-kettle combined chlorination reactor 3, and starting a circulating pump to perform intermittent chlorination reaction while introducing chlorine. And when the chlorine introducing amount reaches 50-60% of the mol fraction of o-xylene in the first-stage tower kettle combined chlorination reactor 3, starting a first-stage circulating pump and cooling water of the cooler 9.
1.3 first order Chlorination
Recovering the chlorination system for feeding, wherein the feeding amount is controlled according to the chlorination reaction speed and the mol ratio of o-xylene to chlorine gas according to a set proportion to be o-xylene: chlorine gas 1: 0.4-0.8, starting a first-stage continuous chlorination reaction. The reaction temperature is 30-40 ℃. When the liquid level of the first-stage tower kettle combined chlorination reactor reaches 60, the flow of circulation and extraction is controlled by a flow meter, so that the material amount entering the second-stage tower kettle combined chlorination reactor 4 is equal to the material amount of the first-stage tower kettle combined chlorination reactor 3, and the balance of feeding and discharging of the first-stage tower kettle combined chlorination reactor 3 is achieved.
1.4 two-stage Chlorination
When the material amount added into the second-stage tower kettle combined chlorination reactor 4 reaches the liquid level of 30%, starting a second-stage circulating pump and a cooler 10, starting a condenser 13, introducing chlorine into the second-stage tower kettle combined chlorination reactor 4, wherein about 50% of o-xylene is unreacted at the moment, and the flow of introduced chlorine is o-xylene: chlorine gas 1: 0.1-0.4, and the reaction temperature is controlled at 30-35 ℃. When the liquid level of the second-stage tower kettle combined chlorination reactor 4 reaches 60%, the circulating and extracting flow is controlled by a flowmeter, so that the material amount entering the third-stage tower kettle combined chlorination reactor 5 is equal to the material amount entering the first-stage tower kettle combined chlorination reactor 3, and the balance of the feeding and discharging of the first-stage tower kettle combined chlorination reactor and the second-stage tower kettle combined chlorination reactor is achieved.
1.5 Tertiary chlorination
When the material amount added into the three-stage tower kettle combined chlorination reactor 5 reaches the liquid level of 30%, starting a three-stage circulating pump and a cooler 11, starting a condenser 14, introducing chlorine into the three-stage tower kettle combined chlorination reactor 5, wherein about 20-40% of o-xylene is unreacted at the moment, and the flow of introduced chlorine is o-xylene: chlorine gas 1: 0.1-0.3, and the reaction temperature is controlled at 10-25 ℃. When the liquid level of the second-stage tower kettle combined chlorination reactor 4 reaches 60%, the circulating and extracting flow is controlled by a flow meter, so that the material amount entering the degassing tower 18 is equal to the material amount entering the first-stage tower kettle combined chlorination reactor 3 at the moment, and the balance of the feeding and discharging of the first-stage, second-stage and third-stage tower kettle combined chlorination reactors is achieved.
After the operation is finished, the continuous chlorination process is opened, and the continuous chlorination operation is carried out. The degassing tower 18 carries out continuous nitrogen degassing, and the chlorinated substances are subjected to nitrogen stripping to remove residual HCl and chlorine in the liquid materials, then enter a chlorinated substance storage tank and then enter the following working procedures.
The invention simplifies the process by directly chlorinating chlorine without solvent, has high yield of monochloro-o-xylene and few by-products, can recycle unreacted o-xylene, and can remove trace HCl remained in the degassed chloride in the subsequent distillation operation.
Examples
EXAMPLE 1 batch Chlorination in a Tower kettle combination reactor
(1) Preparing materials according to the mass ratio of o-xylene: aluminum trichloride is 100: 0.2. 4kg of aluminum trichloride with the water content of less than 100ppm of o-xylene 2124kg and the average particle size of 200 microns is added into a batching kettle 1 replaced by nitrogen and stirred for one hour for standby.
(2) Feeding, starting cooling circulating water of a jacket of a first-stage tower kettle combined chlorination reactor and a condenser 12 at the top of the tower, adding 600kg of materials into a reaction tower 6, and controlling the reaction conditions of o-xylene: the total mole ratio of chlorine gas is 1: 0.8, starting the mechanical stirring and the primary circulating pump of the primary tower kettle combined chlorination reactor 3, starting the HCl absorption and alkali absorption units, simultaneously starting the cooling water of the cooler 9, setting the chlorine introducing speed to be 50kg/h, starting the chlorine introducing reaction, controlling the kettle temperature to be 35 ℃, and finishing the chlorine introducing reaction when the chlorine is introduced to be 321 kg. The mixture is sent into a degassing tower 18 by a first-stage circulating pump for degassing, and the flow rate of the material entering the degassing tower 18 is 72L/h. The degassed material enters a chloride storage tank. And (4) sampling the degassed material, and analyzing the reactant composition and the chlorine utilization rate.
EXAMPLE 2 Single stage continuous Chlorination
(1) Preparing materials according to the mass ratio of o-xylene: aluminum trichloride is 100: 0.2. 4kg of aluminum trichloride with the water content of less than 100ppm of o-xylene 2124kg and the average particle size of 200 microns is added into a batching kettle 1 replaced by nitrogen and stirred for one hour for standby.
(2) And (3) initially feeding, starting cooling circulating water of a first-stage tower kettle combined chlorination reactor jacket and the overhead condenser 12, adding 204L of materials into the reaction tower 6, and stopping feeding. Starting mechanical stirring and a primary circulating pump of the primary tower kettle combined chlorination reactor 3, starting chlorine introducing reaction of the primary tower kettle combined chlorination reactor, simultaneously starting cooling water of the cooler 9, and entering continuous chlorination operation of the next step when 96kg of chlorine is introduced.
(3) Continuous chlorination
Recovering the material kettle 1, feeding the material into a first-stage tower kettle combined chlorination reactor 3 through a reaction tower 6, and controlling the ortho-xylene according to a set mole ratio: the mol ratio of chlorine gas is 1: 0.8, the feeding speed is that the flow rate of dimethylbenzene is 72L/h, the flow rate of chlorine is controlled at 33.91kg/h, a first-stage continuous chlorination reaction is started, and the reaction temperature is controlled to be 40 ℃ through a tower kettle combined chlorination reactor jacket and a cooler. When the total amount of the dimethylbenzene added into the first-stage tower kettle combined chlorination reactor 3 is 600L, the flow of circulation and extraction is controlled by a flow meter, the extracted material enters the degassing tower 18, the amount of the extracted material is 72L/h and is equal to the amount of the material entering the first-stage tower kettle combined chlorination reactor 3, and continuous chlorination of the o-xylene is achieved. The degassed material enters a chloride storage tank. And (4) sampling the degassed material, and analyzing the reactant composition and the chlorine utilization rate.
Example 3 two-stage series continuous Chlorination
(1) Preparing materials according to the mass ratio of o-xylene: aluminum trichloride is 100: 0.2. 4kg of aluminum trichloride with the water content of less than 100ppm of o-xylene 2124kg and the average particle size of 200 microns is added into a batching kettle 1 replaced by nitrogen and stirred for one hour for standby.
(2) The method comprises the steps of initially feeding materials, starting cooling circulating water in a jacket of a tower kettle combined chlorination reactor and the top of a reaction tower, adding 180kg of materials into a 1000L tower kettle combined chlorination reactor provided with a DN150 reaction tower (glass lining materials and ceramic pore plate corrugated structured packing), starting a mechanical stirring and circulating pump to start chlorine introducing reaction, simultaneously starting a circulating pump outlet cooler, stopping introducing chlorine when chlorine is introduced by 60kg, and entering the next step of continuous chlorination operation.
(3) Continuous chlorination
Controlling the ratio of o-xylene: the total mole ratio of chlorine gas is 1: 0.8, recovering the material kettle 1, feeding the material into the first-stage tower kettle combined chlorination reactor 3 through the reaction tower 6, and controlling the o-xylene in the first-stage tower kettle combined chlorination reactor 3 according to a set mole ratio: chlorine gas 1: 0.6, the feeding speed is that the flow rate of dimethylbenzene is 72L/h, the flow rate of chlorine is controlled at 25.43kg/h, the first-stage continuous chlorination reaction is started, and the reaction temperature is controlled to be 40 ℃ by a first-stage tower kettle combined chlorination reactor jacket and a cooler 9. When the total mass of the dimethylbenzene added into the first-stage tower kettle combined chlorination reactor 3 is 600L, the flow of circulation and extraction is controlled by a flow meter, so that the material amount entering the second-stage tower kettle combined chlorination reactor 4 is 72L/h and is equal to the material amount entering the first-stage tower kettle combined chlorination reactor 3, and the balance of feeding and discharging of the first-stage tower kettle combined chlorination reactor 3 is achieved. Meanwhile, chlorine is introduced into the second-stage tower kettle combined chlorination reactor 4, and the flow rate of chlorine is controlled to be 12.71 kg/h. When the material amount added into the second-stage tower kettle combined chlorination reactor 4 reaches 68L, a second-stage circulating pump and a cooler 10 are started, a condenser 13 is started, chlorine is introduced into the second-stage tower kettle combined chlorination reactor 4, and the reaction temperature is controlled at 35 ℃. When the total material amount added into the second-stage tower kettle combined chlorination reactor 4 reaches 600L, the flow of circulation and extraction is controlled by a flow meter, the extracted material enters the degassing tower 18, and the extracted material amount is 72L/h and is equal to the material entering the tower kettle combined chlorination reactor 4. The degassed material enters a chloride storage tank. And (4) analyzing the composition of the reactant and the utilization rate of chlorine after the degassed material is sampled and processed.
EXAMPLE 4 three-stage series continuous Chlorination
(1) Preparing materials according to the mass ratio of o-xylene: aluminum trichloride is 100: 0.2. 4kg of aluminum trichloride with the water content of less than 100ppm of o-xylene 2124kg and the average particle size of 200 microns is added into a batching kettle 1 replaced by nitrogen and stirred for one hour for standby.
(2) The method comprises the steps of initially feeding materials, starting cooling circulating water in a jacket of a tower kettle combined chlorination reactor and the top of a reaction tower, adding 180kg of materials into a 1000L tower kettle combined chlorination reactor provided with a DN150 reaction tower (glass lining materials and ceramic pore plate corrugated structured packing), starting a mechanical stirring and circulating pump to start chlorine introducing reaction, simultaneously starting a circulating pump outlet cooler, stopping introducing chlorine when chlorine is introduced by 60kg, and entering the next step of continuous chlorination operation.
(3) Continuous chlorination
Controlling the ratio of o-xylene: the total mole ratio of chlorine gas is 1: 0.8, recovering the material kettle 1, feeding the material into the first-stage tower kettle combined chlorination reactor 3 through the reaction tower 6, and controlling the o-xylene in the first-stage tower kettle combined chlorination reactor 3 according to a set mole ratio: chlorine gas 1: 0.6, the feeding speed is that the flow rate of dimethylbenzene is 72L/h, the flow rate of chlorine is controlled at 25.43kg/h, the first-stage continuous chlorination reaction is started, and the reaction temperature is controlled at 40 ℃ by a first-stage tower kettle combined chlorination reactor 3 jacket and a cooler 9. When the total mass of dimethylbenzene added into the first-stage tower kettle combined chlorination reactor 3 is 600L, the flow of circulation and extraction is controlled by a flow meter, and extracted materials enter the second-stage reaction tower 7 and then enter the second-stage tower kettle combined chlorination reactor 4 through the second-stage reaction tower 7. The flow rate of the extracted material is 72L/h, which is equal to the material amount entering the first-stage tower kettle combined chlorination reactor 3. Meanwhile, chlorine is introduced into the second-stage tower kettle combined chlorination reactor 4, and the flow rate of chlorine is controlled to be 12.71 kg/h. When the material amount added into the second-stage tower kettle combined chlorination reactor 4 reaches 68L, a second-stage circulating pump and a cooler 10 are started, a condenser 13 is started, and the reaction temperature is controlled at 35 ℃. When the total material amount added into the second-stage tower kettle combined chlorination reactor reaches 600L, the flow of circulation and extraction is controlled by a flow meter, the extracted material enters the third-stage tower kettle combined chlorination reactor 5 through the third-stage reaction tower 8, and the flow of the extracted material is 72L/h. Meanwhile, chlorine is introduced into the three-stage tower kettle combined chlorination reactor 5, and the chlorine flow is 4.24Kg/h, so that the balance of feeding and discharging is achieved. When the material amount added into the second-stage tower kettle combined chlorination reactor 4 reaches 68L, the third-stage circulating pump and the cooler 11 are started, the condenser 14 is started, and the reaction temperature is controlled at 20 ℃. When the total material amount added into the secondary tower kettle combined chlorination reactor reaches 600L, the flow of circulation and extraction is controlled by a flow meter, the extracted material enters the degassing tower 18, and the flow of the extracted material is 72L/h. The material entering the degassing tower 18 is equal to the material entering the third-stage tower kettle combined chlorination reactor 5 in quantity. The degassed material enters a chloride storage tank. And (4) analyzing the composition of the reactant and the utilization rate of chlorine after the degassed material is sampled and processed.
EXAMPLE 5 two-stage series continuous Chlorination
(1) Preparing materials according to the mass ratio of o-xylene: antimony trichloride is 100: 0.4. 4kg of antimony trichloride with the water content of less than 100ppm of o-xylene 2124kg and the average particle size of 250 micrometers is added into a batching kettle 1 replaced by nitrogen and stirred for one hour for standby.
(2) The method comprises the steps of initially feeding materials, starting cooling circulating water in a jacket of a tower kettle combined chlorination reactor and the top of a reaction tower, adding 180kg of materials into a 1000L tower kettle combined chlorination reactor provided with a DN150 reaction tower (glass lining materials and ceramic pore plate corrugated structured packing), starting a mechanical stirring and circulating pump to start chlorine introducing reaction, simultaneously starting a circulating pump outlet cooler, stopping introducing chlorine when chlorine is introduced by 60kg, and entering the next step of continuous chlorination operation.
(3) Continuous chlorination
Controlling the ratio of o-xylene: the total mole ratio of chlorine gas is 1: 0.8, recovering the material kettle 1, feeding the material into the first-stage tower kettle combined chlorination reactor 3 through the reaction tower 6, and controlling the o-xylene in the first-stage tower kettle combined chlorination reactor 3 according to a set mole ratio: chlorine gas 1:0.5, the feeding speed is that the flow rate of dimethylbenzene is 72L/h, the flow rate of chlorine is controlled at 21.19kg/h, a first-stage continuous chlorination reaction is started, and the reaction temperature is controlled to be 40 ℃ by a tower kettle combined chlorination reactor jacket and a cooler. When the total mass of the dimethylbenzene added into the first-stage tower kettle combined chlorination reactor 3 is 600L, the flow of circulation and extraction is controlled by a flow meter, so that the material amount entering the second-stage tower kettle combined chlorination reactor 4 is 72L/h and is equal to the material amount entering the first-stage tower kettle combined chlorination reactor 3, and the balance of feeding and discharging of the first-stage tower kettle combined chlorination reactor 3 is achieved. Meanwhile, chlorine is introduced into the second-stage tower kettle combined chlorination reactor 4, and the flow rate of chlorine is controlled to be 10.59 kg/h. When the material amount added into the second-stage tower kettle combined chlorination reactor 4 reaches 68L, a second-stage circulating pump and a cooler 10 are started, a condenser 13 is started, chlorine is introduced into the second-stage tower kettle combined chlorination reactor 4, and the reaction temperature is controlled at 35 ℃. When the total material amount added into the second-stage tower kettle combined chlorination reactor 4 reaches 600L, the flow of circulation and extraction is controlled by a flow meter, the extracted material enters the degassing tower 18, and the extracted material amount is 72L/h and is equal to the material entering the second-stage tower kettle combined chlorination reactor 4. The degassed material enters a chloride storage tank. And (4) analyzing the composition of the reactant and the utilization rate of chlorine after the degassed material is sampled and processed.
EXAMPLE 6 two-stage series continuous Chlorination
(1) Preparing materials according to the mass ratio of o-xylene: preparing materials with the ratio of ferric trichloride being 100: 0.1. 4kg of ferric trichloride with the water content of less than 100ppm of o-xylene 2124kg and the average particle size of 150 microns is added into the batching kettle 1 replaced by nitrogen and stirred for one hour for standby.
(2) The method comprises the steps of initially feeding materials, starting cooling circulating water in a jacket of a tower kettle combined chlorination reactor and the top of a reaction tower, adding 180kg of materials into a 1000L tower kettle combined chlorination reactor provided with a DN150 reaction tower (glass lining materials and ceramic pore plate corrugated structured packing), starting a mechanical stirring and circulating pump to start chlorine introducing reaction, simultaneously starting a circulating pump outlet cooler, stopping introducing chlorine when chlorine is introduced by 60kg, and entering the next step of continuous chlorination operation.
(3) Continuous chlorination
Controlling the ratio of o-xylene: the total mole ratio of chlorine gas is 1: 0.8, recovering the material kettle 1, feeding the material into the first-stage tower kettle combined chlorination reactor 3 through the reaction tower 6, and controlling the o-xylene in the first-stage tower kettle combined chlorination reactor 3 according to a set mole ratio: chlorine gas 1: 0.7, the feeding speed is that the flow rate of dimethylbenzene is 72L/h, the flow rate of chlorine is controlled at 29.67kg/h, a first-stage continuous chlorination reaction is started, and the reaction temperature is controlled to be 40 ℃ by a tower kettle combined chlorination reactor jacket and a cooler. When the total mass of the dimethylbenzene added into the first-stage tower kettle combined chlorination reactor 3 is 600L, the flow of circulation and extraction is controlled by a flow meter, so that the material amount entering the second-stage tower kettle combined chlorination reactor 4 is 72L/h and is equal to the material amount entering the first-stage tower kettle combined chlorination reactor 3, and the balance of feeding and discharging of the first-stage tower kettle combined chlorination reactor 3 is achieved. Meanwhile, chlorine is introduced into the second-stage tower kettle combined chlorination reactor 4, and the flow rate of chlorine is controlled to be 14.82 kg/h. When the material amount added into the second-stage tower kettle combined chlorination reactor 4 reaches 68L, a second-stage circulating pump and a cooler 10 are started, a condenser 13 is started, chlorine is introduced into the second-stage tower kettle combined chlorination reactor 4, and the reaction temperature is controlled at 35 ℃. When the total material amount added into the second-stage tower kettle combined chlorination reactor 4 reaches 600L, the flow of circulation and extraction is controlled by a flow meter, the extracted material enters the degassing tower 18, and the extracted material amount is 72L/h and is equal to the material entering the second-stage tower kettle combined chlorination reactor 4. The degassed material enters a chloride storage tank. And (4) analyzing the composition of the reactant and the utilization rate of chlorine after the degassed material is sampled and processed.
Comparative example 1 ordinary kettle type chlorination reactor batch reaction
The same procedure and equipment as those in example 1 were adopted, except that the chlorination reactor was a common kettle-type chlorination reactor, the materials were directly added to the reactor, and chlorination was conducted by introducing chlorine into the reactor without circulating outside the reactor.
(1) Preparing materials according to the mass ratio of o-xylene: preparing materials with the ratio of ferric trichloride being 100: 0.25. Adding 15kg of ferric trichloride with the water content of less than 100ppm o-xylene and the average particle size of 300 microns into the batching kettle 1 after nitrogen replacement, and stirring for one hour for later use.
(2) Charging, starting cooling circulating water of a jacket of the kettle type chlorination reactor, adding 615kg of prepared materials into the kettle type chlorination reactor, starting mechanical stirring, starting an HCl absorption and alkali absorption unit, and controlling o-xylene: the total mole ratio of chlorine gas is 1: 0.8, setting the chlorine introduction speed to be 50kg/h, starting chlorine introduction reaction, controlling the kettle temperature to be 35-50 ℃, and finishing chlorine introduction to finish chlorination reaction when the chlorine introduction speed reaches 321 kg. The mixture is sent into a degassing tower 18 by a circulating pump for degassing, and the material flow rate entering the degassing tower 18 is 72L/h. The degassed material enters a chloride storage tank. And (4) sampling the degassed material, and analyzing the reactant composition and the chlorine utilization rate.
Table 1 reactant compositions and chlorine utilization in examples 1-6 and comparative example 1.
The molar ratio of the o-xylene and chlorine feeds in the above reaction is the same 1: 0.8, test and calculation data show that:
(1) compared with the traditional reaction kettle intermittent chlorination, the tower and kettle combined chlorination reactor of the invention can obtain higher effective utilization rate of chlorine gas in both intermittent chlorination, single-stage continuous chlorination and multi-stage continuous chlorination;
(2) the multi-stage series use of the tower and kettle combined chlorination reactor can effectively improve the o-xylene chlorination conversion rate and reduce the production of polychlorinated o-xylene.
In the description herein, reference to the description of the terms "one embodiment/mode," "some embodiments/modes," "example," "specific example," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment/mode or example is included in at least one embodiment/mode or example of the application. In this specification, the schematic representations of the terms used above are not necessarily intended to be the same embodiment/mode or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments/modes or examples. Furthermore, the various embodiments/aspects or examples and features of the various embodiments/aspects or examples described in this specification can be combined and combined by one skilled in the art without conflicting therewith.
Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present application, "plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.
It will be understood by those skilled in the art that the foregoing embodiments are merely for clarity of illustration of the disclosure and are not intended to limit the scope of the disclosure. Other variations or modifications may occur to those skilled in the art, based on the foregoing disclosure, and are still within the scope of the present disclosure.
Claims (12)
1. A method for preparing monochloro-o-xylene by continuously chlorinating o-xylene is characterized by comprising the following steps:
(1) adding the dried o-xylene and the Lewis acid into a batching kettle in proportion, and uniformly stirring;
(2) introducing reactants in the batching kettle into the tower kettle combined chlorination reactor through a reaction tower in the tower kettle combined reactor, introducing dried chlorine into the tower kettle combined chlorination reactor, and controlling the ratio of o-xylene to chlorine so as to carry out continuous chlorination reaction;
(3) and (3) conveying the reaction product chloride of the tower kettle combined chlorination reactor into a degassing tower, removing HCl and residual chlorine in the degassing tower, and conveying the chloride into a chloride storage tank.
2. The method of claim 1, wherein the combined column-bottom reactor comprises a reaction column and a combined column-bottom chlorination reactor, wherein the reaction column is directly installed on the top of the combined column-bottom chlorination reactor or the reaction column is connected above the combined column-bottom chlorination reactor through a pipeline.
3. The method of claim 2, wherein the reaction column of the column-bottom combined reactor is in a structural form comprising a packed column, a sieve plate column or a bubble cap column.
4. The method of claim 1, wherein the material of the combined column-bottom reactor comprises a metal-lined corrosion-resistant non-metallic material; also included are corrosion resistant metal alloy materials.
5. The process according to claim 1, wherein the exothermic heat of chlorination is removed by the combination of a column and a kettle with circulating water in the external jacket of the chlorination reactor and a cooler outside the kettle.
6. The method as claimed in claim 1, wherein in step (2), the combined column-bottom reactor can be used for single-stage independent continuous chlorination reaction or multi-stage series continuous chlorination reaction.
7. The method of claim 6, wherein in the step (2), the combined column-bottom reactor comprises a first-stage combined column-bottom reactor, a second-stage combined column-bottom reactor and a third-stage combined column-bottom reactor.
8. The method of claim 7, wherein step (2) optionally further comprises a four-stage combined column reactor.
9. The method of claim 7,
in a first-stage tower-kettle combined reactor, the reaction conditions are as follows: introducing chlorine gas at the mol ratio of 1:0.5-0.8, and controlling the chlorination reaction temperature to be 30-70 ℃;
in a two-stage tower-kettle combined reactor, the reaction ratio of o-xylene: introducing chlorine gas at the mol ratio of 1:0.4-0.6, and controlling the chlorination reaction temperature to be 5-40 ℃;
in a three-stage tower-kettle combined reactor, the reaction conditions are as follows: introducing chlorine gas with the mol ratio of 1:0.3-0.5, and controlling the chlorination reaction temperature to be 0-40 ℃.
10. The method according to claim 1, wherein the molar ratio of the o-xylene to the Lewis acid in the step (1) is 100:0.01 to 1.
11. The method according to claim 1, wherein the Lewis acid is selected from one or more of ferric trichloride, aluminum trichloride, antimony trichloride and stannic tetrachloride.
12. The method of claim 1, further comprising:
and cooling the chloride which is the reaction product of the tower kettle combined chlorination reactor before the chloride is sent to a degassing tower.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110981321.4A CN113563153B (en) | 2021-08-25 | 2021-08-25 | Method for preparing monochloro-ortho-xylene by continuous chlorination of ortho-xylene |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110981321.4A CN113563153B (en) | 2021-08-25 | 2021-08-25 | Method for preparing monochloro-ortho-xylene by continuous chlorination of ortho-xylene |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113563153A true CN113563153A (en) | 2021-10-29 |
| CN113563153B CN113563153B (en) | 2024-01-23 |
Family
ID=78172647
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110981321.4A Active CN113563153B (en) | 2021-08-25 | 2021-08-25 | Method for preparing monochloro-ortho-xylene by continuous chlorination of ortho-xylene |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113563153B (en) |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1080278A (en) * | 1992-06-17 | 1994-01-05 | 中国科学院长春应用化学研究所 | Preparation method of monochloro-o-xylene |
| JP2003342206A (en) * | 2002-05-28 | 2003-12-03 | Toray Ind Inc | METHOD FOR PRODUCING 4-CHLORO-o-XYLENE |
| CN1944408A (en) * | 2006-06-30 | 2007-04-11 | 衢州恒顺化工有限公司 | Process for preparing symmetric tetrachloro pyridine |
| CN101397234A (en) * | 2007-09-30 | 2009-04-01 | 浙江省常山长盛化工有限公司 | Method for preparing dichlorobenzene |
-
2021
- 2021-08-25 CN CN202110981321.4A patent/CN113563153B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1080278A (en) * | 1992-06-17 | 1994-01-05 | 中国科学院长春应用化学研究所 | Preparation method of monochloro-o-xylene |
| JP2003342206A (en) * | 2002-05-28 | 2003-12-03 | Toray Ind Inc | METHOD FOR PRODUCING 4-CHLORO-o-XYLENE |
| CN1944408A (en) * | 2006-06-30 | 2007-04-11 | 衢州恒顺化工有限公司 | Process for preparing symmetric tetrachloro pyridine |
| CN101397234A (en) * | 2007-09-30 | 2009-04-01 | 浙江省常山长盛化工有限公司 | Method for preparing dichlorobenzene |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113563153B (en) | 2024-01-23 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108752161B (en) | Method for synthesizing monochloro-o-xylene in continuous flow microchannel reactor | |
| CN109134231B (en) | Device and process for continuously producing chloroacetic acid by differential circulation | |
| PL205828B1 (en) | Method of chlorine purification and process for producing 1,2-dichloroethane | |
| CN102923664B (en) | Method for producing hydrogen fluoride by virtue of gas-solid-liquid associative reaction method | |
| AU2016212452A1 (en) | Vanadium pentoxide purifying system and method | |
| CN108997284B (en) | Method for synthesizing chlorophthalic anhydride in continuous flow micro-channel reactor | |
| CN114874178A (en) | Production method and production system of vinylene carbonate | |
| CN111455406A (en) | Preparation method of high-purity beryllium chloride and nuclear pure-grade metal beryllium | |
| CN110283039A (en) | A kind of preparation method of fluorobenzene | |
| CN108610314B (en) | Method for synthesizing biphenyl dianhydride in continuous flow microchannel reactor | |
| CN106892792B (en) | Continuous synthesis method and equipment of 3, 4-dichloro benzotrifluoride | |
| CN117229253B (en) | Method for continuously preparing high-purity chloroethylene carbonate | |
| CN113563153B (en) | Method for preparing monochloro-ortho-xylene by continuous chlorination of ortho-xylene | |
| CN104592012A (en) | Continuous production method and device for chloroformyl substituted benzenes | |
| CN100537521C (en) | Method for synthesizing N,N dimethyl acetamide in high purity | |
| CN116253644A (en) | Method for preparing 4-nitro-1-naphthol by dynamic tubular reactor | |
| US3190931A (en) | Method for oxychlorination of hydrocarbons | |
| CN113842858B (en) | Reaction tower with reaction shallow pool and method for preparing ethylene carbonate by using reaction tower | |
| CN103896332B (en) | Prepare the method and system of titanium dioxide | |
| CN113880730B (en) | Industrial method for continuously preparing hexamethylene diisocyanate | |
| JPS60116635A (en) | Manufacture of 1,2-dichloroethane from ethylene and chlorinegas | |
| US5608083A (en) | Process for the production of phthalic anhydride | |
| CN104478698B (en) | A kind of method of continuous seepage stearyl chloride | |
| CN114950320A (en) | Device and method for continuously synthesizing tetrafluoroethane-beta-sultone | |
| CN114835564A (en) | Method for producing photoinitiator UV-1173 by condensation method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |