CN1903814A - Production method of para chlorotoluene - Google Patents
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Abstract
The present invention relates to a production method of high-purity p-chlorotoluene. Said method includes the following steps: using L-type zeolite molecular sieve as catalyst, using low-grade halogenated saturated alkanol or low-grade halogenated saturated fully acid or its potassium and sodium salt as cocatalyst, making toluene and chlorine gas be fully reacted, then aerating, removing chlorine gas and hydrogen chloride from reaction solution, rectifying to remove unreacted toluene and tolylchloride, then more adding L-type zeolite molecular sieve catalyst, continuously introducing chlorine gas to make reaction, after said reaction is completed, aerating, removing chlorine gas and hydrogen chloride, further making rectification and separation so as to obtain high-purity p-chloro to luene.
Description
Technical field
The present invention relates to a kind of production method of parachlorotoluene, particularly relate to a kind of production method of oriented chlorination of toluene production high purity parachlorotoluene.
Background technology
Parachlorotoluene is a kind of important Organic Chemicals, is widely used in making meticulous organic chemical industry's products such as agricultural chemicals, medicine, dyestuff.Parachlorotoluene is produced by toluene ring chlorine reaction, but with common Louis's acid as catalyst, in the resulting monochlorotoluene of toluene ring chlorination reaction, major part is an ortho-chlorotolu'ene, and parachlorotoluene only accounts for 30%～35%.Because the purposes of parachlorotoluene is big more than ortho-chlorotolu'ene, for this reason, must select suitable ring chlorination reaction directional catalyst, to improve the ratio of parachlorotoluene in the toluene ring chlorination reaction, prevailing method is when using lewis acid catalyst, adds SULPHUR POWDER or inorganic sulfide compound or organosulfur compound simultaneously as directed co-catalyst.For example people (US4647709,1987) such as H.Wolfram makes catalyzer with butter of antimony, with 1,3,7, and 9-tetrachloro-2,8-dimethyl Fen Evil thiophene is directed co-catalyst, with chlorine toluene is encircled chlorination reaction, parachlorotoluene/ortho-chlorotolu'ene=1.67.
Zeolite molecular sieve is a kind of environment-friendly catalyst, and many organic reactions are all had catalytic activity and catalytic selectivity, and dissimilar molecular sieves has different catalytic activitys and catalytic selectivity.Zeolite molecular sieve starts from the eighties in 20th century as the para-selectivity ring chlorination reaction that catalyzer is used for toluene, and used catalyzer mainly is the Y zeolite of aperture 5～13 and L type molecular sieve etc.United States Patent (USP) (US4724269,1988) report, with the zeolite L molecular sieve is catalyzer, with the chloro fat alcohol that contains 2～3 carbon atoms is co-catalyst, toluene carries out chlorination reaction under the temperature that is not higher than the reaction mixture boiling point, control reaction end with gas-chromatography, the transformation efficiency 87.6% of toluene, parachlorotoluene/ortho-chlorotolu'ene=3.356, the selectivity of parachlorotoluene (with respect to the total amount of reaction product) is 75%.Afterwards, India scholar A.P.Sing and S.B.Kumar (AppliedCatalysis A.General, nineteen ninety-five.126:27) by showing after the systematic study, the zeolite L molecular sieve is the optimum catalyst of toluene para-selectivity ring chlorination reaction, and effect obviously is better than X type, Y type and ZSM-5 type etc.Yet through experimental results show that, though it is all higher than coming with respect to other catalyzer to the neighbour, but the ratio of contained meta-isomer is generally all 0.5%～1.0% in the product, can not satisfy the specification of quality of high-purity parachlorotoluene, and catalyzer can not recycle, production cost is increased, so can not really in suitability for industrialized production, be applied.
Chinese patent (CN1261068A, 1999; CN1257059A, 1999) report, with activated zeolite attapulgite clay, atlapulgite is catalyzer, with the Iron sulfuret is cocatalyst, toluene carries out chlorination reaction under 30 ℃～50 ℃ temperature, when toluene level in the reaction solution＜0.3% is reaction end, the transformation efficiency 99.7% of toluene, parachlorotoluene/ortho-chlorotolu'ene=1/1.1～1/1.2.This method technology is simple, catalyst levels is few, but lower to adjacent chlorine.Therefore industrial prospect is little.
Summary of the invention
The production method that the purpose of this invention is to provide a kind of high purity parachlorotoluene, the content of position, ortho isomer between the inventive method can reduce, the content height of parachlorotoluene.
The present invention realizes like this.The production method of high purity parachlorotoluene of the present invention, be as catalyzer with the zeolite L molecular sieve, with the lower halogenated saturated fatty alcohol, perhaps lower halogenated saturated fatty acid or its potassium, sodium salt is as co-catalyst, make toluene and chlorine carry out liquid phase ring chlorination reaction, after reacting completely, aeration, remove the chlorine and the hydrogen chloride gas that remain in the reaction solution, reaction solution falls unreacted toluene by rectifying separation, obtain the reaction solution after the rectifying behind the ortho-chlorotolu'ene, to wherein adding the zeolite L molecular sieve catalyst, continue introduce chlorine gas to make reaction, after reacting completely, aeration, remove the chlorine and the hydrogen chloride gas that remain in the reaction solution, reaction solution obtains the high purity parachlorotoluene through rectifying separation again.
The SiO of described zeolite L molecular sieve
2/ Al
2O
3Mol ratio be 4～8, the aperture is 6～10 , its consumption is every mole of toluene 0.1～25g; Described lower halogenated saturated fatty alcohol is the alcohol that contains 2～3 carbon atoms, and its consumption is every mole of toluene 0.01～10g; Described lower halogenated saturated fatty acid or its potassium, sodium salt are the acid that contains 2～3 carbon atoms, and its consumption is every mole of toluene 0.01～10g; Described adding chlorine quantity is every mole of toluene 70～100g.
The inventive method, described lower halogenated saturated fatty alcohol is an ethylene chlorhydrin, 2,2-dichlroroethanol, trichloro-ethyl alcohol, 2,2,2 tfifluoroethyl alcohol, trimethylene chlorohydrin, 2, a kind of in 3-two trimethylewne chlorohydrin 3-s.
The inventive method, described lower halogenated saturated fatty acid or its potassium, sodium salt are a kind of in Monochloro Acetic Acid, dichloro acetic acid, trichoroacetic acid(TCA), alpha-chloro propionic acid, β-chloropropionic acid, trifluoroacetic acid, dichloro acetic acid potassium, the dichloroacetate sodium.
The inventive method, described ring chlorination reaction temperature is for being 20 ℃～100 ℃.
The inventive method, described ring chlorination reaction are to adopt tower chlorination or still formula chlorating mode to carry out, and the chlorination plant material is a lass lining, and its aspect ratio is 15～1: 1.
The inventive method, described reaction solution and catalyst separating are to adopt the mode of press filtration to carry out, and filtering equipment is the PE millipore filter, and its PE filter core aperture is between 5 μ～50 μ.
The inventive method, described rectifying separation are to separate with rectifying tower, and the form of rectifying tower is a packing tower, and filler is a CY type mesh ripple packing.
Zeolite molecular sieve also can use metal-salts such as potassium, sodium, calcium, magnesium, iron, nickel, copper through ion-exchanged.
Method of the present invention, described through being reused for down batch chlorination reaction after the press filtration recovery catalyzer process activation treatment.The method that catalyst regeneration adopted is after extracting organism adsorbed in the catalyzer with the steam stripped mode of water vapour, again with repeatedly washing, filtering, 150 ℃～180 ℃ bakings 15～20 hours, can be reused for following batch chlorination reaction in 3～4 hours 400 ℃～500 ℃ roastings more earlier.
The present invention compared with prior art has the following advantages:
1. adopt the production method of a kind of parachlorotoluene of the present invention, the content of position, ortho isomer between can reducing, the purity of raising parachlorotoluene.
2. the inventive method can make adjacent chlorine ratio height, because the parachlorotoluene price is far above ortho-chlorotolu'ene at present, therefore, economic benefit is obvious.
3. to select eco-friendly zeolite for use be main catalyzer to the inventive method, reclaims catalyzer after manipulation of regeneration, can be recycled, and production cost is low, non-secondary pollution.
4. the inventive method technical process is simple and direct, and equipment is simple, and operation control is easy, the quality product height, and production cost is low, adopts the inventive method to produce parachlorotoluene, and is free from environmental pollution.
Embodiment
In order to implement the present invention better, the present invention is further illustrated now to enumerate following embodiment, but the present invention is not limited to the scope of the cited embodiment of the inventor.
Embodiment 1
In the four-hole boiling flask that prolong, Chlorination tube, stirring, thermometer are housed, add the freshly prepd zeolite L molecular sieve of 350g, 3500g (1mol) toluene and 130g ethylene chlorhydrin, open and stir, with mixture heating up to 50 ℃, speed with 2mol/hr feeds chlorine then, exothermic heat of reaction, feed liquid are warming up to 75 ℃, and feed temperature was 75 ℃～80 ℃ when chlorine was led in control, after reaction is finished, the intensification aeration rushes to remain in chlorine and hydrogen chloride gas in the reaction solution, cooling, filtering recovering catalyst, this catalyzer are handled through regeneration activating and are used for following batch chlorination reaction; Filtrate is mixed-chlorotoluene, parachlorotoluene/ortho-chlorotolu'ene=4.16 wherein, many chlorine compounds 3.55%, m-chlorotoluene 0.86%, toluene conversion 98.32%.
Mixed-chlorotoluene enters toluene tower, reclaims a small amount of unreacted toluene, reclaims toluene and is reused for chlorination reaction; Tower still material enters adjacent tower and separates ortho-chlorotolu'ene, content greater than 99.20% ortho-chlorotolu'ene as by-product; Ortho-chlorotolu'ene content is put in the chlorination tank less than 0.20% parachlorotoluene (containing m-chlorotoluene, many toluene(mono)chlorides etc.) again in the tower still, the catalyzer of the present invention that adds 10% weight, be warming up to 75 ℃ and feed chlorine, feed temperature was 75 ℃～80 ℃ when chlorine was led in control, after the m-chlorotoluene complete reaction, stop logical chlorine, the intensification aeration rushes to remain in chlorine and hydrogen chloride gas in the reaction solution, cooling, filtering recovering catalyst, this catalyzer are handled through regeneration activating and are used for following batch chlorination reaction; Filtrate enters separates smart tower, obtains content greater than 99.70% high purity parachlorotoluene product.
The reaction of toluene and chlorine is to carry out with tower chlorination or still formula chlorating mode, and the chlorination plant material is a lass lining, and its aspect ratio is 15～1: 1.Reaction solution and catalyst separating are to adopt the mode of press filtration to carry out, and filtering equipment is the PE millipore filter, and its PE filter core aperture is between 5 μ～50 μ.Rectifying separation is to separate with rectifying tower, and the form of rectifying tower is a packing tower, and filler is a CY type mesh ripple packing.
Embodiment 2
The preparation of zeolite L molecular sieve:
Press K
2O: Al
2O
3: SiO
2: H
2The mol ratio of O is 8: 1: 12: 300 are made into gel, in 130 ℃ of crystallization 5 hours, make crystallization director.Press K again
2O: Al
2O
3: SiO
2: H
2The mol ratio of O is 4.2: 1.0: 10: 160 are made into gel, add the crystallization director of 5 weight %, and in 150 ℃ of crystallization 19 hours, elimination liquid was washed with water to pH=10～10.5, and oven dry is then in 540 ℃ of roastings 5 hours.Fragmentation, levigate, sieve, make 100 purpose powdery zeolite L molecular sieves, place airtight containers for future use.Before the use, roasting 3 hours again under 500 ℃ of temperature.
Also can be made into preformed catalyst and use, method for making is as follows: silicon sol (is contained 30% SiO
2) and zeolite L mix and stir moulding by weight 3: 7, dry, broken, the screening diameter be the particle of 0.1mm～0.3mm in 500 ℃ of following roastings 4 hours, promptly get preformed catalyst.
Embodiment 3
Chlorination reaction:
In reaction flask, add 8g zeolite L molecular sieve, 92.1g (1mol) toluene, 3g chloroethanol, with mixture heating up to 70 ℃, and keep this temperature, the speed with about 0.25mol/hr feeds chlorine then, after reaction was finished, the intensification aeration rushed to remain in chlorine and hydrogen chloride gas in the reaction solution, cooling, filtering recovering catalyst, parachlorotoluene/ortho-chlorotolu'ene in the filtrate=3.25, many chlorine compounds 7.6%, m-chlorotoluene 0.9%, the transformation efficiency 88.6% of toluene.
Embodiment 4
Chlorination reaction:
Chloroethanol with among the Mono Chloro Acetic Acid replacement embodiment 1 repeats the experiment of embodiment 1, parachlorotoluene/ortho-chlorotolu'ene in the reaction solution=3.65, many toluene(mono)chlorides 5.8%, m-chlorotoluene 0.7%, the transformation efficiency 96.3% of toluene.
Embodiment 5
Chlorination reaction under the modified zeolite catalysis:
7.5g Repone K is dissolved in the 300ml distilled water, be heated to 90 ℃, add 30g Na-L type zeolite molecular sieve, stir, with the mixture evaporate to dryness, then in baking oven in 130 ℃ dry 15 hours down, at last in retort furnace in 500 ℃ of following roastings 5 hours, obtain containing the zeolite L molecular sieve of 20%KCl.
Replace 8g zeolite L molecular sieve with the above-mentioned KCl-type zeolite molecular sieve that makes of 10g, repeat the experiment of embodiment 1, in the reaction solution, parachlorotoluene/ortho-chlorotolu'ene=3.55, many toluene(mono)chlorides 6.8%, m-chlorotoluene 0.8%, the transformation efficiency 94.6% of toluene.
Embodiment 6
Reduce the chlorination reaction of meta-isomer:
In reaction flask, add the mixed-chlorotoluene that 400g contains meta-isomer 0.95%, add 40gKCl-type zeolite molecular sieve, open and stir, be warming up to 75 ℃, and controlled temperature is between 75 ℃～80 ℃, with the speed of 0.3mol/hr per hour toward wherein feeding chlorine, after reacting completely, reaction solution carries out rectifying again and can obtain the high purity parachlorotoluene through aeration.Can not reuse repeatedly and this catalyzer is treated.
Embodiment 7
The regeneration of spent catalyst and repeated use:
Get in the reaction flask of spent catalyst 50g adding 500ml, add 300ml water, open and stir, be heated to and boil, in ventpipe, constantly feed water vapour again, organism catalyzer is adsorbed with the steam stripped mode of water vapour steams, and till no oily matter distillated, the reusable heat water washing repeatedly, filter, earlier 150 ℃～160 ℃ dryings 15～20 hours, again in retort furnace in 400 ℃～500 ℃ roastings 2～5 hours, take out and in vacuum drier, be cooled to room temperature.
Take by weighing above-mentioned treated catalyzer 20g, be added in the 200g toluene, add the 6.5g chloroethanol again, repeat the experiment of embodiment 1, parachlorotoluene/ortho-chlorotolu'ene in the reaction solution=3.58, many toluene(mono)chlorides 3.54%, m-chlorotoluene 0.86%, toluene conversion are 98.28%.
This catalyzer can adopt this mode constantly to be circulated in the chlorination reaction.
Claims (8)
1, a kind of production method of parachlorotoluene, it is characterized in that: use the zeolite L molecular sieve as catalyzer, with the lower halogenated saturated fatty alcohol, perhaps lower halogenated saturated fatty acid or its potassium, sodium salt is as co-catalyst, make toluene and chlorine carry out liquid phase ring chlorination reaction, after reacting completely, aeration, remove the chlorine and the hydrogen chloride gas that remain in the reaction solution, reaction solution falls unreacted toluene by rectifying separation, obtain the reaction solution after the rectifying behind the ortho-chlorotolu'ene, to wherein adding the zeolite L molecular sieve catalyst, continue introduce chlorine gas to make reaction, after reacting completely, aeration, remove the chlorine and the hydrogen chloride gas that remain in the reaction solution, reaction solution obtains the high purity parachlorotoluene through rectifying separation again;
The SiO of described zeolite L molecular sieve
2/ Al
2O
3Mol ratio be 4～8, the aperture is 6～10 , its consumption is every mole of toluene 0.1～25g; Described lower halogenated saturated fatty alcohol is the alcohol that contains 2～3 carbon atoms, and its consumption is every mole of toluene 0.01～10g; Described lower halogenated saturated fatty acid or its potassium, sodium salt are the acid that contains 2～3 carbon atoms, and its consumption is every mole of toluene 0.01～10g; Described adding chlorine quantity is every mole of toluene 70～100g.
2, the method for claim 1 is characterized in that described lower halogenated saturated fatty alcohol is an ethylene chlorhydrin, 2,2-dichlroroethanol, trichloro-ethyl alcohol, 2,2,2 tfifluoroethyl alcohol, trimethylene chlorohydrin, 2, a kind of in 3-two trimethylewne chlorohydrin 3-s.
3, the method for claim 1 is characterized in that described lower halogenated saturated fatty acid or its potassium, sodium salt are a kind of in Monochloro Acetic Acid, dichloro acetic acid, trichoroacetic acid(TCA), alpha-chloro propionic acid, β-chloropropionic acid, trifluoroacetic acid, dichloro acetic acid potassium, the dichloroacetate sodium.
4, the method for claim 1 is characterized in that described ring chlorination reaction temperature is for being 20 ℃～100 ℃.
5, the method for claim 1 is characterized in that: described ring chlorination reaction is to adopt tower chlorination or still formula chlorating mode to carry out, and the chlorination plant material is a lass lining, and its aspect ratio is 15～1: 1.
6, the method for claim 1 is characterized in that: described reaction solution and catalyst separating are to adopt the mode of press filtration to carry out, and filtering equipment is the PE millipore filter, and its PE filter core aperture is between 5 μ～50 μ.
7, the method for claim 1 is characterized in that: described rectifying separation is to separate with rectifying tower, and the form of rectifying tower is a packing tower, and filler is a CY type mesh ripple packing.
8, the method for claim 1, it is characterized in that: described chlorination reaction is carried out in the presence of solvent, and described solvent is rudimentary chloroparaffin, and rudimentary chloroparaffin is 1,2-ethylene dichloride, tetracol phenixin, solvent load are every mole of toluene 50～300g.
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Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN102134179A (en) * | 2010-12-29 | 2011-07-27 | 安徽八一化工股份有限公司 | Process for producing monochlorobenze by chlorination of pure benzene |
| CN101492344B (en) * | 2008-11-04 | 2011-09-28 | 丹阳中超化工有限公司 | P-chlorotoluene purification process |
| CN102603468A (en) * | 2012-02-21 | 2012-07-25 | 南通市东昌化工有限公司 | Production method of p-chlorotoluene |
| CN102794196A (en) * | 2012-09-03 | 2012-11-28 | 浙江师范大学 | Catalyst for methylbenzene directional chlorination reaction and preparation method thereof |
| CN103467243A (en) * | 2013-09-16 | 2013-12-25 | 江苏大学 | Method for catalyzing toluene selective chlorination by using H-L type molecular sieve |
| CN108467333A (en) * | 2018-04-27 | 2018-08-31 | 江苏优普生物化学科技股份有限公司 | The method that toluene continuous chlorination produces parachlorotoluene |
| CN109734551A (en) * | 2019-01-10 | 2019-05-10 | 江苏琦衡农化科技有限公司 | A kind of oriented chlorination of toluene prepares the production technology of p-chlorotoluene |
| CN114436766A (en) * | 2022-02-25 | 2022-05-06 | 常州新东化工发展有限公司 | Method for producing high-purity o-chlorotoluene by adsorption separation method |
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2005
- 2005-07-29 CN CNB2005100282691A patent/CN100509721C/en active Active
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN101492344B (en) * | 2008-11-04 | 2011-09-28 | 丹阳中超化工有限公司 | P-chlorotoluene purification process |
| CN102134179A (en) * | 2010-12-29 | 2011-07-27 | 安徽八一化工股份有限公司 | Process for producing monochlorobenze by chlorination of pure benzene |
| CN102603468A (en) * | 2012-02-21 | 2012-07-25 | 南通市东昌化工有限公司 | Production method of p-chlorotoluene |
| CN102794196A (en) * | 2012-09-03 | 2012-11-28 | 浙江师范大学 | Catalyst for methylbenzene directional chlorination reaction and preparation method thereof |
| CN102794196B (en) * | 2012-09-03 | 2014-07-02 | 浙江师范大学 | Catalyst for methylbenzene directional chlorination reaction and preparation method thereof |
| CN103467243A (en) * | 2013-09-16 | 2013-12-25 | 江苏大学 | Method for catalyzing toluene selective chlorination by using H-L type molecular sieve |
| CN103467243B (en) * | 2013-09-16 | 2015-04-22 | 江苏大学 | Method for catalyzing toluene selective chlorination by using H-L type molecular sieve |
| CN108467333A (en) * | 2018-04-27 | 2018-08-31 | 江苏优普生物化学科技股份有限公司 | The method that toluene continuous chlorination produces parachlorotoluene |
| CN109734551A (en) * | 2019-01-10 | 2019-05-10 | 江苏琦衡农化科技有限公司 | A kind of oriented chlorination of toluene prepares the production technology of p-chlorotoluene |
| CN114436766A (en) * | 2022-02-25 | 2022-05-06 | 常州新东化工发展有限公司 | Method for producing high-purity o-chlorotoluene by adsorption separation method |
| CN114436766B (en) * | 2022-02-25 | 2023-11-03 | 常州新东化工发展有限公司 | Method for producing high-purity o-chlorotoluene by adsorption separation method |
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Effective date of registration: 20200714 Address after: 312369 No.8, Beitang East Road, Shangyu economic and Technological Development Zone, Hangzhou Bay, Shaoxing City, Zhejiang Province Patentee after: Wei Zhejiang Huaxin materials Limited by Share Ltd. Address before: 322109 No. 128, industrial road, Weishan Town, Zhejiang, Dongyang Patentee before: Zhejiang Weihua Chemical Co.,Ltd. |
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