Process for preparing 1-chlorobutane
阅读说明：本技术 1-氯丁烷的制备方法 (Process for preparing 1-chlorobutane ) 是由 邱化齐 李璞 李剑 于 2020-12-28 设计创作，主要内容包括：本发明属于精细化工技术领域,具体涉及一种1-氯丁烷的制备方法。将反应溶剂、水与正丁醇混合,加入氯化试剂反应,得到1-氯丁烷；其中,反应溶剂为2,3,5,6-四甲基二氧六环。本发明采用一锅法制备,方法简单,安全性好,易于实施,对设备要求低,可连续化生产；避免了传统金属催化剂污染大的问题,三废少,对环境友好；采用2,3,5,6-四甲基二氧六环作为反应溶剂及催化剂,能有效的避免丁烯、二丁醚及聚合树脂等副产物的产生,提高了收率和产品质量,产品摩尔收率96％以上,气相纯度99.7％以上。(The invention belongs to the technical field of fine chemical engineering, and particularly relates to a preparation method of 1-chlorobutane. Mixing a reaction solvent, water and n-butyl alcohol, and adding a chlorination reagent to react to obtain 1-chlorobutane; wherein the reaction solvent is 2,3,5, 6-tetramethyl dioxane. The invention adopts a one-pot method for preparation, has simple method, good safety, easy implementation and low requirement on equipment, and can realize continuous production; the problem of large pollution of the traditional metal catalyst is avoided, three wastes are less, and the method is environment-friendly; 2,3,5, 6-tetramethyl dioxane is used as a reaction solvent and a catalyst, so that the generation of byproducts such as butylene, dibutyl ether, polymer resin and the like can be effectively avoided, the yield and the product quality are improved, the molar yield of the product is more than 96%, and the gas phase purity is more than 99.7%.)
1. A preparation method of 1-chlorobutane is characterized in that a reaction solvent, water and n-butanol are mixed, and a chlorination reagent is added for reaction to obtain 1-chlorobutane; wherein the reaction solvent is 2,3,5, 6-tetramethyl dioxane.
2. The process for the preparation of 1-chlorobutane according to claim 1, wherein the volume ratio of the reaction solvent, water and n-butanol is 5-15: 1: 1-15.
3. The method of claim 1, wherein the chlorinating agent is hydrogen chloride gas.
4. The process for the preparation of 1-chlorobutane according to claim 1, wherein the molar ratio of n-butanol to chlorinating agent is 1: 2-5.
5. The method according to claim 1, wherein the reaction temperature is 80-115 ℃ and the reaction time is 1-3 hours.
6. The preparation method of the 1-chlorobutane is characterized by comprising the following steps:
(1) mixing a reaction solvent, water and n-butanol, adding a chlorination reagent for reaction to obtain a reaction solution, and distilling the reaction solution to obtain 1-chlorobutane; wherein the reaction solvent is 2,3,5, 6-tetramethyl dioxane;
(2) and continuously introducing n-butanol into the reaction solution to react with a chlorination reagent, and continuously preparing the 1-chlorobutane after distillation.
7. The process for producing 1-chlorobutane according to claim 6, wherein the volume ratio of the reaction solvent, water and n-butanol in the step (1) is 5 to 15: 1: 1-15, wherein the molar ratio of the n-butanol to the chlorinating agent is 1: 2-5.
8. The method according to claim 6, wherein the chlorinating agent used in step (1) is hydrogen chloride gas, and the reaction temperature is 80-115 ℃.
9. The method according to claim 6, wherein the n-butanol is introduced at a rate of 1 to 10ml/min and the chlorinating agent is introduced at a rate of 1 to 10g/min in the step (2).
10. The method according to claim 6, wherein the chlorinating agent in step (2) is hydrogen chloride gas, and the reaction temperature is 80-115 ℃.
Technical Field
The invention belongs to the technical field of fine chemical engineering, and particularly relates to a preparation method of 1-chlorobutane.
Background
The 1-chlorobutane is an important fine chemical product and can be used for grease, rubber, natural resin solvents, medical intermediates, cocatalysts and the like. At present, the method is mainly used for preparing an olefin polymerization catalyst, namely butyl lithium, preparing butyl tin products through a Grignard reaction, preparing phenylbutazone in medicine, preparing insecticide myclobutanil in pesticide, and using the butyl tin products as a solvent in polyether production. The current market demands more than 99% of products, wherein the purity requirement of 1-chlorobutane for synthesizing n-butyllithium is more than or equal to 99.5%.
In the prior art, n-butanol and hydrochloric acid or hydrogen chloride gas are mainly used as raw materials to synthesize 1-chlorobutane, and the main synthesis methods comprise the following steps:
chinese patent CN 101475440A discloses a method for continuously producing n-butyl chloride by reacting n-butanol with hydrogen chloride gas in the absence of a catalyst. However, the patent does not give specific yield information, and the equipment is complex and the investment cost of production equipment is high.
The method for producing n-butyl chloride disclosed in the Chinese patent CN 1069018A uses concentrated hydrochloric acid to replace hydrogen chloride gas, and after the reaction is finished, the purity of the product can reach 99% through chromatographic analysis, and the yield is 90%.
New technology for synthesizing 1-chlorobutane, Qiu billow, etc., fine chemical engineering, 2004, 21(8):637-638 and preparation of n-butyl chloride, Chinese chlor-alkali, such as Bighui, 2003, (10):43 discloses the use of ZnC12FeC1 as the main catalyst3As the cocatalyst, HC1 gas and concentrated hydrochloric acid are respectively used for catalytic chlorination of n-butanol, and compared with the catalyst-free catalyst under the same condition, the yield can be improved by about 6%. However, ZnC1 in the catalytic process2And FeC13Is difficult to recover, the content of heavy metal ions in the wastewater is high, and the environmental pollution is very serious.
Chinese patent CN 1440958A discloses a method for converting primary alcohol or cyclohexanol in acidic ionic liquid [ Hmim ] + X- (X ═ Cl, Br, I) into halogenated hydrocarbon, wherein N-methylimidazolium hydrochloride ionic liquid (both used as solvent and chlorinating agent) is reacted with N-butanol to obtain 1-chlorobutane, and after the reaction is finished, N-methylimidazolium hydrochloride ionic liquid is regenerated by concentrated hydrochloric acid and is continuously used in the next batch. Although the yield of the method is high (about 95%), the method has the advantages that the ionic liquid and the 1-chlorobutane are difficult to delaminate after the reaction is finished, and the delamination takes longer time, so that the production period can be prolonged in industrial production, the production efficiency is reduced, and the industrial production is not facilitated; meanwhile, when the concentrated hydrochloric acid is used for recovering the ionic liquid, further distillation is needed for removing water, the water is difficult to completely remove, the reaction is probably greatly influenced, and whether the recovered ionic liquid can maintain the yield of about 95% in the patent is not reported.
Chinese patent CN 104326863 a discloses a method for preparing 1-chlorobutane, which comprises the following steps: mixing a catalyst, a chlorinating agent and water, stirring, then mixing with n-butyl alcohol, and carrying out chlorination reaction to obtain 1-chlorobutane; the catalyst is dimethyl sulfoxide, the chlorination reagent is hydrogen chloride, and the molar ratio of the chlorination reagent to n-butyl alcohol is 2.5: 1-5: 1; the stirring temperature is 15-45 ℃. The method has the advantages of long reaction time, reaction time of more than 20 hours, high energy consumption, no contribution to industrialization and low yield of only about 90 percent.
In addition, the above patents inevitably produce by-products, such as butene, dibutyl ether and polymer resin, which are difficult to separate and are not suitable for continuous production. Therefore, it is urgently needed to provide a preparation method of 1-chlorobutane, which has the advantages of simple method, good safety, easy implementation, continuous production, environmental protection, no pollution, and high product yield and purity.
Disclosure of Invention
The invention aims to provide a preparation method of 1-chlorobutane, which solves the problems of complex process, high equipment requirement, high pollution, more byproducts and the like of the existing synthesis process, has the advantages of simple and easy operation, continuous production, environmental protection, no pollution, high product yield and high product purity, and is more suitable for industrial production.
The reaction mode of the invention is batch reaction or continuous reaction.
When the reaction mode is an intermittent reaction, the preparation method of the 1-chlorobutane comprises the steps of mixing a reaction solvent, water and n-butyl alcohol, and adding a chlorination reagent for reaction to obtain the 1-chlorobutane; wherein the reaction solvent is 2,3,5, 6-tetramethyl dioxane.
The volume ratio of the reaction solvent, water and n-butanol is 5-15: 1: 1-15, preferably 8-10: 1: 5-10.
The chlorination reagent is hydrogen chloride gas.
The mol ratio of the n-butanol to the chlorinating agent is 1: 2-5, preferably 1: 2.5-3.
The reaction temperature is 80-115 ℃, preferably 95-105 ℃; the reaction time is 1-3 hours.
When the reaction mode is a continuous reaction, the preparation method of the 1-chlorobutane comprises the following steps:
(1) mixing a reaction solvent, water and n-butanol, adding a chlorination reagent for reaction to obtain a reaction solution, and distilling the reaction solution to obtain 1-chlorobutane; wherein the reaction solvent is 2,3,5, 6-tetramethyl dioxane;
(2) and continuously introducing n-butanol into the reaction solution to react with a chlorination reagent, and continuously preparing the 1-chlorobutane after distillation.
The volume ratio of the reaction solvent, water and n-butanol in the step (1) is 5-15: 1: 1-15, preferably 8-10: 1: 5-10.
The chlorination reagent in the step (1) is hydrogen chloride gas.
The mol ratio of the n-butanol to the chlorinating agent in the step (1) is 1: 2-5, preferably 1: 2.5-3.
The reaction temperature in step (1) is 80 to 115 ℃, preferably 95 to 105 ℃.
The speed of introducing the n-butanol in the step (2) is 1-10ml/min, and the speed of introducing the chlorinating agent is 1-10 g/min.
And (3) the chlorination reagent in the step (2) is hydrogen chloride gas.
The reaction temperature in the step (2) is 80 to 115 ℃, preferably 95 to 105 ℃.
The chemical reaction equation of the invention is as follows:
the n-butyl alcohol is easy to generate intramolecular dehydration to form ether or eliminate reaction to form alkene under the high-temperature acidic condition, and the 2,3,5, 6-tetramethyl dioxane is used as a reaction solvent to obtain high-purity 1-chlorobutane; the 2,3,5, 6-tetramethyl dioxane has high boiling point, can provide higher reaction temperature, has good solubility to hydrogen chloride, improves the reaction rate, avoids the generation of byproducts and improves the yield.
The invention has the following beneficial effects:
(1) the invention adopts a one-pot method for preparation, has simple method, good safety, easy implementation and low requirement on equipment, and can realize continuous production;
(2) the invention avoids the problem of large pollution of the traditional metal catalyst, has less three wastes and is environment-friendly;
(3) the invention adopts 2,3,5, 6-tetramethyl dioxane as reaction solvent and catalyst, can effectively avoid the generation of by-products such as butylene, dibutyl ether and polymer resin, and the like, improves the yield and the product quality, and has the product molar yield of more than 96 percent and the gas phase purity of more than 99.7 percent;
(4) the method has mild reaction conditions, the reaction solvent is also a catalyst, the solvent can be simply distilled, recycled and reused, and the process is simple; compared with the prior art, the method has the advantages of low cost, high product purity and high yield.
Drawings
FIG. 1 is a chromatogram of 1-chlorobutane obtained in example 1.
FIG. 2 is a chromatogram of n-butanol and dibutyl ether.
FIG. 3 is a chromatogram of 1-chlorobutane obtained in comparative example 1.
Detailed Description
The present invention is further described below with reference to examples.
Example 1
200ml of 2,3,5, 6-tetramethyl dioxane, 20ml of purified water and 200ml (2.19mol) of n-butyl alcohol are added into a three-neck flask with the capacity of 1000ml and provided with a stirrer and a thermometer, the temperature is raised to 105 ℃ while stirring, 199.8g (5.48mol) of hydrogen chloride gas is introduced, distillation is carried out while reaction is carried out, a fraction is gradually and slowly distilled off along with the extension of the reaction time, almost no fraction is further distilled after the heat preservation distillation and the reaction are carried out for 2h, the reaction is finished, the obtained fraction is layered, the upper organic layer is 1-chlorobutane, 195.4g (2.11mol) of 1-chlorobutane is finally obtained, the molar yield is 96.3%, the GC purity is 99.83%, and the chromatographic results are shown in a graph 1 and a table 1. Calibrating a 1-chlorobutane standard product by GC to obtain a product, namely 1-chlorobutane, wherein the retention time is 3.968'; the n-butyl and dibutyl ethers were also calibrated and the retention times were 4.249 'and 9.690', respectively, and the chromatographic results are shown in FIG. 2 and Table 2.
Table 1 chromatographic peak table for example 1
Peak number
Retention time
Area of
Height
Area%
1
2.965
17292
10066
0.078
2
3.418
1507
896
0.007
3
3.635
2637
1206
0.012
4
3.968
22193351
8039738
99.831
5
4.990
1861
769
0.008
6
5.135
12646
4828
0.057
7
9.516
1723
496
0.008
Total of
22231016
8058000
100.000
TABLE 2 chromatogram peaks for n-butyl and dibutyl ethers
Peak number
Retention time
Area of
Height
Area%
1
3.471
2620
1142
0.012
2
3.771
4798
1605
0.021
3
3.847
2633
731
0.012
4
3.986
56829
24898
0.253
5
4.249
17747223
2504253
78.925
6
8.198
2382
547
0.011
7
9.690
4661566
953773
20.731
8
10.755
3647
889
0.016
9
11.598
1024
270
0.005
10
13.042
3520
1017
0.016
Total of
22486241
3489126
100.000
Example 2
300ml of 2,3,5, 6-tetramethyl dioxane, 20ml of purified water and 200ml (2.19mol) of n-butyl alcohol are added into a three-neck flask with the capacity of 1000ml and provided with a stirrer and a thermometer, the temperature is raised to 115 ℃ by stirring, 196.4g (5.38mol) of hydrogen chloride gas is introduced, the distillation is carried out while the reaction is carried out, the fraction is gradually and slowly distilled off along with the extension of the reaction time, almost no fraction is further distilled after the heat preservation distillation and the reaction are carried out for 2h, the reaction is finished, the obtained fraction is layered, the upper organic layer is 1-chlorobutane, 195.9g (2.12mol) of 1-chlorobutane is finally obtained, the molar yield is 96.6%, and the GC purity is 99.79%.
Example 3
100ml of 2,3,5, 6-tetramethyl dioxane, 20ml of purified water and 200ml (2.19mol) of n-butyl alcohol are added into a three-neck flask with the capacity of 1000ml and provided with a stirrer and a thermometer, the temperature is raised to 85 ℃ while stirring, 239.8g (6.57mol) of hydrogen chloride gas is introduced, distillation is carried out while reaction is carried out, a fraction is gradually and slowly distilled off along with the extension of the reaction time, almost no fraction is further distilled after the heat preservation distillation and the reaction are carried out for 3 hours, the reaction is finished, an upper organic layer is 1-chlorobutane after the obtained fraction is layered, 194.6g (2.11mol) of 1-chlorobutane is finally obtained, the molar yield is 96.0%, and the GC purity is 99.87%.
Example 4
Adding 200ml of 2,3,5, 6-tetramethyldioxane, 20ml of purified water and 200ml (2.19mol) of n-butyl alcohol into a three-neck flask with the capacity of 1000ml and a stirrer and a thermometer, stirring and heating to 105 ℃, introducing 199.8g (5.48mol) of hydrogen chloride gas, distilling while reacting, gradually distilling a fraction slowly with the extension of reaction time, adding n-butyl alcohol into a reaction bottle at the speed of 5ml/min by using a peristaltic pump after 100ml of the fraction is distilled out, adding 800ml (8.74mol) of n-butyl alcohol, keeping the introduction speed of 5g/min of hydrogen chloride gas in the adding process, after the heat preservation distillation and the reaction are finished for 2 hours, almost not distilling any fraction, finishing the reaction, layering the obtained fraction, obtaining an upper organic layer which is 1-chlorobutane, finally obtaining 979.3g (10.58mol) of 1-chlorobutane, wherein the molar yield is 96.8%, the GC purity was 99.87%.
Example 5
Adding 300ml of 2,3,5, 6-tetramethyl dioxane, 20ml of purified water and 200ml (2.19mol) of n-butyl alcohol into a 1000ml three-neck flask with a stirrer and a thermometer, stirring and heating to 115 ℃, introducing 196.4g (5.38mol) of hydrogen chloride gas, carrying out reaction and distillation, gradually distilling a fraction slowly with the extension of reaction time, adding n-butyl alcohol into a reaction bottle at the speed of 3ml/min by using a peristaltic pump after 100ml of the fraction is distilled out, adding 800ml (8.74mol) of n-butyl alcohol, keeping the introduction speed of 3g/min of hydrogen chloride gas in the adding process, after carrying out heat preservation distillation and reaction for 2h, almost not distilling any fraction, finishing the reaction, layering the obtained fraction, obtaining an upper organic layer which is 1-chlorobutane, finally obtaining 980.6g (10.59mol) of 1-chlorobutane and having the molar yield of 96.9%, the GC purity was 99.89%.
Example 6
Adding 100ml of 2,3,5, 6-tetramethyldioxane, 20ml of purified water and 200ml (2.19mol) of n-butyl alcohol into a 1000ml three-neck flask with a stirrer and a thermometer, stirring and heating to 85 ℃, introducing 239.8g (6.57mol) of hydrogen chloride gas, distilling while reacting, gradually slowly distilling a fraction with the prolonging of reaction time, adding the n-butyl alcohol into the reaction flask at the speed of 8ml/min by using a peristaltic pump after distilling the fraction out of 100ml, adding 800ml (8.74mol) of n-butyl alcohol, keeping the introduction speed of the hydrogen chloride gas at 8g/min in the adding process, after the heat preservation distillation and the reaction are finished for 3 hours, almost not distilling any fraction, layering the obtained fraction, obtaining an upper organic layer which is 1-chlorobutane, finally obtaining 978.5g (10.57mol) of 1-chlorobutane with the molar yield of 96.7%, the GC purity was 99.84%.
Comparative example 1
860mL of concentrated hydrochloric acid was charged into a 3L reaction flask, and 1363g (10mol) of anhydrous zinc chloride was added in portions while cooling, and stirred so that the zinc chloride was dissolved as much as possible. 371g (5mol) of n-butanol was added, the oil bath was heated to 150 ℃ and the solution started to boil, HCl was bubbled in and 1-chlorobutane was distilled off, and the 75.5-77.5 ℃ fraction was collected to give 355g of 1-chlorobutane, 76% molar yield, 97.53% GC purity, 1.208% dibutyl ether, and the chromatographic results are shown in FIG. 3 and Table 3.
TABLE 3 chromatographic Peak Table for comparative example 1
Peak number
Retention time
Area of
Height
Area%
1
2.968
1661
941
0.009
2
3.417
4041
2275
0.021
3
3.635
1760
771
0.009
4
3.733
1263
436
0.007
5
3.963
18352746
7023137
97.526
6
4.036
157488
86681
0.837
7
4.989
9398
4050
0.050
8
9.508
227374
76598
1.208
9
10.647
4337
1382
0.023
10
11.799
39407
4524
0.209
11
12.950
14894
4477
0.079
12
13.905
4024
1203
0.021
Total of
18818394
7206476
100.000