CN1057992C - Method for preparation of methane polychloride - Google Patents
Method for preparation of methane polychloride Download PDFInfo
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- CN1057992C CN1057992C CN96102981A CN96102981A CN1057992C CN 1057992 C CN1057992 C CN 1057992C CN 96102981 A CN96102981 A CN 96102981A CN 96102981 A CN96102981 A CN 96102981A CN 1057992 C CN1057992 C CN 1057992C
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- methane
- chlorine
- polychloride
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- monochloro methane
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Abstract
This invention relates to suppress the production of water in a reactional system and efficiently produce a high-order chlorinated methane.This method for producing high-order chlorinated methane is to distill chlorine, react the purified chlorine obtained as a still residue with methyl chloride, provide a reactional mixture containing the high-order chlorinated methane and the unreacted methyl chloride, then preferably separate hydrogen chloride, subsequently separate the resultant reactional mixture into the high-order chlorinated methane and unreacted methyl chloride and refeed the separated unreacted methyl chloride into the step for reacting the purified chlorine with the methyl chloride.
Description
The present invention relates to the manufacture method of methane polychloride.
Make the monochloro methane chlorination, the method that makes the methane polychloride of methylene dichloride, trichloromethane, tetracol phenixin is known.In this chlorination reaction, can obtain to contain the reaction mixture of methane polychloride and unreacted monochloro methane.But also it is known, for separation and purification from this reaction mixture as the methane polychloride of object, after this reaction mixture distillation, at first isolate the hydrogenchloride of coexistence, go out unreacted monochloro methane through fractionation by distillation similarly then, the gained methane polychloride is begun to separate in order from low-boiling compound.And, in this separation purification method,, the above-mentioned unreacted monochloro methane that is removed is supplied with in the reaction process of chlorination reaction once more in order to improve the reactivity of the monochloro methane in the chlorination reaction operation.
Yet, in the manufacture method of above-mentioned methane polychloride,,, in system, generate liquid or gas with severe corrosive because chlorine and hydrogenchloride coexistence are arranged if having water to exist in the reaction system.Therefore, in the manufacture method of this methane polychloride,, all earlier it is contacted fully to dewater with dewatering agent such as sulfuric acid usually as the monochloro methane of raw material.And chlorine uses too and to take off water, perhaps if liquid chlorine then earlier carries out gasification process with it with gasifiers such as flash vessels.
Yet,, in reaction system, still generate considerable moisture even remove moisture in the raw material like this.And, this water, when above-mentioned reaction mixture distills out unreacted monochloro methane, the azeotropic mixture of formation and this monochloro methane flows out from the distillation cat head with monochloro methane.Therefore, when utilizing the technical process that above-mentioned the sort of unreacted monochloro methane is supplied with the reaction process of chlorination reaction once more to make methane polychloride, with this unreacted monochloro methane also with water supply chlorination reaction operation, carrying out along with reaction, this water is also put aside in system gradually, thereby produces the problem that makes corrosion of equipment.
Therefore there is the people to propose, at the distillation cat head of from above-mentioned reaction mixture, isolating unreacted monochloro methane, setting is filled with the dewatering tank of calcium chloride etc., make effusive unreacted monochloro methane dehydration, but because the discarded problem of calcium chloride after having complicated calcium chloride filling operation and using, thereby the usage quantity of this calcium chloride preferably reduces as much as possible.In view of above situation, people wish to develop a kind of can the inhibited reaction system in the generation of water, make the method for methane polychloride efficiently.
Present inventors make great efforts research according to above problem.It found that, as the chlorine that uses in the chlorination reaction, if use then can reduce the water yield that generates because of chlorination reaction widely, thereby finish the present invention by the chlorine of distillation purifying.
Just, the present invention relates to a kind of manufacture method of methane polychloride, it is characterized in that, chlorine is distilled, and the pure chlorine and the monochloro methane that obtain as the still resistates are reacted, thereby obtain to contain the reaction mixture of methane polychloride and unreacted monochloro methane, then this reaction mixture is separated into methane polychloride and unreacted monochloro methane after, this unreacted monochloro methane of separating is supplied with once more the reaction process of above-mentioned pure chlorine and monochloro methane.
In the present invention, make the method for pure chlorine and monochloro methane reaction, can be without any the currently known methods that restrictedly adopts as the chlorination reaction of making methane polychloride.Especially in the presence of the radical that is produced by free-radical initiator and/or ultraviolet ray, and the method that monochloro methane and chlorine are reacted is good.By this chlorination reaction, obtain to contain the methane polychloride that trichloromethane, tetracol phenixin are formed and the reaction mixture of unreacted monochloro methane by methylene dichloride.
In the present invention, as the chlorine that in above-mentioned methane polychloride manufacturing process, uses, use be the pure chlorine that obtains by distillation.Therefore, in the manufacturing of this methane polychloride, the water yield of generation can significantly reduce.
Herein, the distillation of chlorine can be adopted known method, has no particular limits.Usually preferably at 5-15kg/cm
2Under the pressure of G, the jar liquid temp in the distillation tower is implemented distillation in 12.0-55.0 ℃ scope.Distillation tower can be the tower of any structures such as known buffle-type tower or packing tower.Under the situation of buffle-type tower, the baffle plate number of plies is good with the 3-8 layer.And, from the cat head expellant gas, can be whole discharges, but generally preferably be cooled to 0-40 ℃ with water cooler, under this temperature, discharge the gas phase.Herein, the composition by the cooling of said temperature is liquefied is back to distillation tower usually again.Reflux ratio has no particular limits, but is generally 0-300, preferred 3-100.From the chlorine that cat head obtains, the chlorine that does not reflux contains more impurity, thereby is preferably used in the unchallenged purposes of impurity.Be used to cool off the cooling agent of the water cooler of overhead gas, can make water etc., also can use 0-5 ℃ salt solution or chlorinated hydrocarbons cooling agent.In addition, as distillatory thermal source, preferably steam, warm water etc.The chlorine of supplying with can be gas or liquid, or gas-liquid mixture.
The volume of the chlorine under 20 ℃ and the normal pressure in the purifying chlorine technology shared ratio in all gas more than 99.975 volume %, preferably is embodied as the best when 99.990 volume %.Purity testing that should refining chlorine according to the method for JISK1102, is decided to be 2000ml with the treatment capacity of chlorine, uses a kind of special eudiometer of nation (Bunte burette) that can handle such large volume chlorine to measure, and the mensuration temperature is decided to be 20 ℃.
In the present invention, supply with the purity of the chlorine that records with aforesaid method before distilling, be generally 99.4-99.965 volume %.
And, even do not distill but, the raw material of raffinate as methane polychloride used, also can reach and suppress the effect that water generates to a certain degree, but also contain a large amount of chlorine in the gas phase of discharging, thereby can not look to improving the service efficiency of chlorine the flash distillation of a chlorine part.
In the present invention, chlorine can use any chlorine, preferably uses the chlorine that generates and supply with in the electrolyzer of salt usually.And this chlorine preferably reduced its moisture with dewatering agents such as sulfuric acid as much as possible before supplying with distillation.Usually preferably use water-content to be the chlorine below the 30ppm.On the other hand, distilled still resistates is pure chlorine, obtains with liquid state usually, but this liquid chlorine, and preferably boosting with pump is transferred near the reactor of above-mentioned chlorination reaction, makes it to resupply after the gasification.
On the other hand, the monochloro methane of Shi Yonging contacts with dewatering agents such as sulfuric acid in advance in the present invention, makes it dewater to re-use below 10ppm to water-content and be advisable.
Among the present invention,, from above-mentioned reaction mixture, isolate methane polychloride and unreacted monochloro methane for the purifying methane polychloride.And, in above-mentioned reaction mixture, except this methane polychloride and unreacted monochloro methane, also contain hydrogenchloride usually.Among the present invention, the reaction mixture that supplies above-mentioned methane polychloride and unreacted monochloro methane separating technology to use also can contain hydrogenchloride, but preferably separate the mixture of this hydrogenchloride in advance.The separation of this hydrogenchloride is preferably implemented by distillation.
In the present invention, from above-mentioned reaction mixture, be separated into the method for methane polychloride and unreacted monochloro methane, have no particular limits, can adopt known method.Generally be to utilize the difference of the boiling point of each composition to become methane polychloride and unreacted monochloro methane by fractionation by distillation.And, the methane polychloride of forming by methylene dichloride, trichloromethane, tetracol phenixin of acquisition, preferably further with its distillation, make its each begin to separate in turn since low-boiling compound.
On the other hand, in the present invention, the unreacted monochloro methane that is separated, the chlorination reaction rate for the monochloro methane that improves use infeeds in the reaction process of above-mentioned pure chlorine and monochloro methane once more.This unreacted monochloro methane, owing to use the raw material of pure chlorine as above-mentioned chlorination reaction, thereby the content of water is reduced greatly, and therefore in the present invention, the corrosion of equipment problem that unreacted monochloro methane is produced during the supply response operation once more significantly improves.
In the present invention, from the effusive unreacted monochloro methane in monochloro methane distillation tower top, also can carry out drying by contacting with dewatering agents such as calcium chloride, zeolites.Under this occasion, among the present invention,, therefore can significantly reduce the usage quantity of this dewatering agent owing to can reduce aforesaid water content greatly.Herein, with contacting of this dewatering agent, both can be the unreacted monochloro methane of gas phase that after the distillation tower outflow, takes out immediately, also can be the unreacted monochloro methane of liquid phase that this vapor condensation forms.And in the present invention, separated unreacted monochloro methane both can be with its full dose supply response operation once more, also can be only with its a part of supply response operation, and remaining supplies with the monochloro methane distillation tower once more, or is moved to outside the reaction system.
And then, among the present invention, in order to improve the output of the more methane polychlorides of chlorinity such as trichloromethane, tetracol phenixin, can be with isolated methylene dichloride similarly offers in the reaction process of pure chlorine and monochloro methane once more by distillation in the above-mentioned methane polychloride.
Below further describe the present invention with reference to the accompanying drawings.
Fig. 1 is the methane polychloride manufacture method sketch chart of expression typical embodiments of the present invention.Among Fig. 1,, at first supply with chlorine distillation tower 2 and distill by pipe arrangement 1 as the chlorine of chlorination reaction raw material.Then, be the liquid pure chlorine of still resistates by what take out at the bottom of the tower of this chlorine distillation tower 2, boost by pump 3, infeed chlorination reactor 6 by gasifier 4 gasification backs by pipe arrangement 5.On the other hand, in this chlorination reactor 6, supply with monochloro methane by pipe arrangement 7.So, in this chlorination reactor 6,, generate and contain the methane polychloride of forming by methylene dichloride, trichloromethane, tetracol phenixin by the chlorination reaction of monochloro methane, and the reaction mixture of unreacted monochloro methane.And, in this reaction mixture, also contain hydrogenchloride.
Then, this reaction mixture is at first infeeded in the hydrogenchloride distillation tower 9 by pipe arrangement 8, and hydrogenchloride is isolated from top of tower in the distillation back.Subsequently, the mixture that contains methane polychloride and unreacted monochloro methane from the tower bottom of hydrogenchloride distillation tower 9 is discharged infeeds in the monochloro methane distillation tower 11 by pipe arrangement 10.Then, said mixture is distilled in this monochloro methane distillation tower 11, isolates unreacted monochloro methane by top of tower.And, in this isolated unreacted monochloro methane, also can be mixed with methylene dichloride.From the methane polychloride that the tower bottom of monochloro methane distillation tower 11 is discharged, supply with methylene dichloride distillation tower 12 thereafter, and then supply with trichloromethane distillation tower 13, isolate each composition in proper order from low-boiling beginning in this way., between monochloro methane distillation tower 11 and the methylene dichloride distillation tower 12, washing procedure, a washing step that is used to wash the alkaline aqueous solutions such as aqueous sodium hydroxide solution of methane polychloride can be set as required also herein, and dehydration procedure etc.And in methylene dichloride distillation tower 12 and trichloromethane distillation tower 13, methylene dichloride and trichloromethane normally take out by inciting somebody to action overhead gas condensation separately, but also can take out by the position of the required theoretical plate number section of leaving cat head.
On the other hand, the unreacted monochloro methane gas phase of being discharged by the cat head of monochloro methane distillation tower 11 after delivering to water cooler 15 and be liquefied by pipe arrangement 14, as required, infeeds in the dewatering tank 16 that is filled with dewatering agents such as calcium chloride.Then, pass this dewatering tank 16 and the unreacted monochloro methane that is dried, infeed once more in the chlorination reactor 6, become once more the raw material of chlorination reaction by pipe arrangement 17.At this moment, this unreacted monochloro methane also can infeed monochloro methane distillation tower 11, or be moved to outside the reaction system once more with its part by pipe arrangement 18 or pipe arrangement 19.Also can be as required, the same with this unreacted monochloro methane, isolating methylene dichloride in above-mentioned methylene dichloride distillation tower 12 also can be used as in the raw material supplying chlorination reactor 6 of chlorination reaction.
According to the present invention, in the chlorination reaction of monochloro methane, can significantly reduce the amount of moisture of generation.Its result with unreacted monochloro methane, supplies with in the reaction process of monochloro methane and chlorine once more, also can suppress the corrosion of the reaction unit that the savings owing to water causes widely.And the unreacted monochloro methane that will be separated by the monochloro methane distillation tower can reduce the usage quantity of this dewatering agent, thereby prolong its duration of service greatly with in the dewatering agent exsiccant occasions such as calcium chloride.
For the present invention more specifically is described, enumerate following embodiment and comparative example and describe, but the present invention is not subjected to the qualification of this embodiment.
Produce methane polychloride by manufacturing process shown in Figure 1.The chlorine that uses is the liquid chlorine of the moisture 3.5ppm of being divided into that generates in the salt electrolysis device.Making the purity of measuring after this liquid chlorineization is 99.6 volume %
Stage number: 5 layers
The temperature of jar liquid in the distillation tower: 40 ℃
The cooling temperature of overhead gas: 27 ℃
Reflux ratio: 25
Raw material chlorine feed rate: 7356kg/H
The output of pure chlorine: 7270kg/H
The moisture pure chlorine that is divided into 3.5ppm by above-mentioned distillation obtains resupplies in the chlorination reactor 6 after gasifier 4 gasifications of forming with flash vessel.The purity of the chlorine behind the purifying is 99.9975 volume %.On the other hand, the feed rate that infeeds in the chlorination reactor 6 from the monochloro methane of pipe arrangement 7 is defined as 3410kg/H.The moisture 9ppm that is divided into of this monochloro methane.And, in the dewatering tank 16 that the unreacted monochloro methane that the spy separates dewaters, be filled with calcium chloride 550kg.By the unreacted monochloro methane of this processed, it 50% is infeeded in the monochloro methane distillation tower 11 by pipe arrangement 18, all the other are infeeded in the chlorination reactor 6 once more by pipe arrangement 17.
In service at above manufacturing process detects the water content of the unreacted monochloro methane in dewatering tank 16 exits.Consequently, the water content of the unreacted monochloro methane in the above-mentioned place of initial operating stage is 60ppm, and the water separation capability that continues to be filled in the calcium chloride in the dewatering tank along with operation lowers, thereby this water content surpasses 100ppm after 115 days.
In embodiment 1, by the distillation condition of following change chlorine.
Stage number: 7 layers
Distillation tower pressure: 12.0kg/cm
2G
The temperature of jar liquid in the distillation tower: 45 ℃
The cooling temperature of overhead gas: 32 ℃
Reflux ratio: 89
Raw material chlorine feed rate: 7356kg/H
The output of pure chlorine: 7270kg/H
Except that above condition, similarly to Example 1, obtaining to be refined into purity is the above pure chlorine of 99.9975 volume %, is used for making methane polychloride then.
Initial operating stage is 60ppm in the water content of the unreacted monochloro methane in dewatering tank 16 exits, and this value needs 306 when surpassing 100ppm.
The moisture 3.5ppm that is divided into that use obtains in embodiment 1, the purity that the gasification back is measured is the liquid chlorine of 99.965 volume %, and it is distilled by following condition.
Stage number: 5 layers
Distillation tower pressure: 10.5kg/cm
2G
Jar liquid temp in the distillation tower: 40 ℃
The cooling temperature of overhead gas: 29 ℃
Reflux ratio: 58
Raw material chlorine feed rate: 7356kg/H
The output of pure chlorine: 7348kg/H
Except that above condition, other similarly to Example 1, obtaining purity is the pure chlorine of 99.9975 volume %, uses it for the manufacturing methane polychloride then.
Initial operating stage is 60ppm in the water content of the unreacted monochloro methane in dewatering tank 16 exits, and this value needs 108 when surpassing 100ppm.
Comparative example 1
In embodiment 3, remove and chlorine not distilled, and directly with gasifier 4 make infeed in the chlorination reactor 6 after the liquid chlorineization outside, other are by method manufacturing methane polychloride similarly to Example 1.Initial operating stage is 60ppm at the water-content of the unreacted monochloro methane in dewatering tank 16 exits, and this value surpassed 100ppm in 13 days.
Fig. 1 is the sketch chart as the methane polychloride manufacture method of typical embodiments of the present invention.
Nomenclature is as follows among the figure.
1: the pipe arrangement of supplying with chlorine
2: the chlorine distillation tower
3: pump
4: gasifier
5: the pipe arrangement that pure chlorine is infeeded chlorination reactor
6: chlorination reactor
7: the pipe arrangement of supplying with monochloro methane
8: the pipe arrangement that chlorination reactor and hydrogenchloride distiller are coupled together
9: the hydrogenchloride distillation tower
10: the pipe arrangement that hydrogenchloride distillation tower and monochloro methane distillation tower are coupled together
11: the monochloro methane distillation tower
12: the methylene dichloride distillation tower
13: the trichloromethane distillation tower
14: the pipe arrangement of discharging the unreacted monochloro methane from the monochloro methane distillation tower
15: water cooler
16: dewatering tank
17: the pipe arrangement of unreacted monochloro methane being supplied with once more chlorination reactor
18: the pipe arrangement of unreacted monochloro methane being supplied with once more the monochloro methane distillation tower
19: unreacted monochloro methane is shifted out the outer pipe arrangement of reaction system
Claims (11)
1. the preparation method of methane polychloride, it is characterized in that, chlorine is distilled, and use the pure chlorine and the monochloro methane that obtain as the still resistates to react, thereby obtain to contain the reaction mixture of methane polychloride and unreacted monochloro methane, after then this reaction mixture being separated into methane polychloride and unreacted monochloro methane, this unreacted monochloro methane of separating is supplied with once more the reaction process of above-mentioned pure chlorine and monochloro methane.
2. the preparation method of the described methane polychloride of claim 1, wherein, the distillation of chlorine is at 5-15kg/cm
2Under the pressure of G, a jar liquid temp is to carry out under 12.0-55.0 ℃ in the distillation tower.
3. the preparation method of the described methane polychloride of claim 1, wherein, the purity that the distillation of chlorine proceeds to chlorine is the above degree of 99.975 volume %.
4. the preparation method of the described methane polychloride of claim 1, wherein, the distillation of chlorine is the cat head distilled chlorine of distillation tower to be back to steam full tower to carry out.
5. the described methane polychloride preparation method of claim 1, wherein, the reaction of pure chlorine and monochloro methane is in the presence of the radical that is produced by free-radical initiator and/or ultraviolet ray, and monochloro methane is under the state of liquid phase and carries out.
6. the preparation method of the described methane polychloride of claim 1, wherein, the moisture content of pure chlorine is below the 30ppm.
7. the preparation method of the described methane polychloride of claim 1, wherein, the moisture content of pure chlorine is below the 10ppm.
8. the preparation method of the described methane polychloride of claim 1 wherein, makes the reaction of pure chlorine and monochloro methane, after obtaining to contain methane polychloride and unreacted monochloro methane reaction mixture, goes out hydrogenchloride by fractionation by distillation.
9. the preparation method of the described methane polychloride of claim 1, wherein, separating of methane polychloride and unreacted monochloro methane is to be undertaken by distillation.
10. the preparation method of the described methane polychloride of claim 9 wherein, makes from the unreacted monochloro methane of cat head distilled of distillation tower to contact with dewatering agent.
11. the preparation method of the described methane polychloride of claim 10, wherein, described dewatering agent is to be selected from least a in calcium chloride, zeolite, calcium sulfate, the sodium sulfate.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7349995 | 1995-03-30 | ||
| JP73499/95 | 1995-03-30 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1137511A CN1137511A (en) | 1996-12-11 |
| CN1057992C true CN1057992C (en) | 2000-11-01 |
Family
ID=13520017
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN96102981A Expired - Lifetime CN1057992C (en) | 1995-03-30 | 1996-03-28 | Method for preparation of methane polychloride |
Country Status (1)
| Country | Link |
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| CN (1) | CN1057992C (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101503336B (en) * | 2009-03-06 | 2013-03-13 | 刘世刚 | Improved methane chloride production process |
| CN103626624A (en) * | 2012-08-29 | 2014-03-12 | 曹汉平 | Method for preventing corrosion on methane chloride chlorination device |
| CN104230650B (en) * | 2013-06-21 | 2016-01-20 | 徐家乐 | A kind of light chlorination process prepares the technique of methyl chloride |
| CN107814683A (en) * | 2017-11-08 | 2018-03-20 | 安徽东至广信农化有限公司 | A kind of production technology of dichloromethane |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS61233638A (en) * | 1985-04-09 | 1986-10-17 | Kanegafuchi Chem Ind Co Ltd | Production of dichloroethane |
| EP0260650A2 (en) * | 1986-09-18 | 1988-03-23 | The B.F. Goodrich Company | Process for minimizing corrosion due to moisture in vent gases from a high temperature direct chlorination reactor for converting ethylene |
-
1996
- 1996-03-28 CN CN96102981A patent/CN1057992C/en not_active Expired - Lifetime
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS61233638A (en) * | 1985-04-09 | 1986-10-17 | Kanegafuchi Chem Ind Co Ltd | Production of dichloroethane |
| EP0260650A2 (en) * | 1986-09-18 | 1988-03-23 | The B.F. Goodrich Company | Process for minimizing corrosion due to moisture in vent gases from a high temperature direct chlorination reactor for converting ethylene |
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| CN1137511A (en) | 1996-12-11 |
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