CN1323770A

CN1323770A - C1-C4 alkyl halide producing process

Info

Publication number: CN1323770A
Application number: CN 00112278
Authority: CN
Inventors: 顾浩
Original assignee: Individual
Current assignee: Individual
Priority date: 2000-05-12
Filing date: 2000-05-12
Publication date: 2001-11-28

Abstract

The preparation of C1-4 alkyl halide is carried out by direct reaction of C1-4 alcohol and halogen acid in reactor and is characterized in that the mole ratio of halogen acid and C1-4 alcohol in reaction within unit time (minute) is larget than 1000, when the produced C1-4 alkyl halide is alkyl bromide, the reaction temperature in reactor is higher than 125 deg.C, when producing alkyl chloride, the reaction temperature in reactor is higher than 109 deg.C. Because it uses high temperature and high mole ratio, the reaction path can complete and the purity of reaction product alkyl halide can reach about 99%.

Description

The production method of C1-4 haloalkane

The present invention relates to the production technique that the production method of haloalkane, particularly direct method prepare rudimentary C1-4 haloalkane.

The C1-4 haloalkane has a wide range of applications aspect organic synthesis, and the old production technique of C1-4 haloalkane is to make catalyzer with sulfuric acid, and the pure and mild haloid acid reaction of C1-4 generates haloalkane, and this process recovery ratio is low and have a large amount of sulfur waste acid to have serious three wastes.Adopted the pure and mild haloid acid direct reaction with C1-4 in the recent period, made catalyzer without sulfuric acid, the no sulfuric acid three wastes produce, and its yield also increases.European patent: " (publication number: 0446537A1); disclose the production technique of direct method continuous production lower halogenated alkane; the content of its lower halogenated alkane is about 98%; content of impurity isomer is greater than 0.5%; because the content and the impurity of haloalkane have bigger influence to its synthetic quality product is so need further to improve purity for preparation lower halogenated alkane technology.

The objective of the invention is to put forward a kind of production method that can improve C1-4 haloalkane purity and yield of arch.

The production method that realizes the object of the invention is: it be is characterized in that by the pure and mild haloid acid of C1-4 direct reaction in reactor: haloid acid and the C1-4 alcohol mol ratio in the unit time (branch) is greater than 1000 in the reactor; When adopting Hydrogen bromide to produce bromoalkane, the temperature control in its reactor is greater than 125 ℃; Temperature control when adopting spirit of salt production alkyl chloride in its reactor is greater than 109 ℃.

Since in the process of reaction when acid and pure mol ratio are above greater than 1000, speeding up of reaction, reaction process is complete, and increase along with mol ratio, speed of response increases progressively, reaction process is complete more, improves temperature of reaction and can improve speed of response, and the temperature control in reactor is very important.When adopting Hydrogen bromide to produce bromoalkane, the temperature control in its reactor is greater than 125 ℃; Temperature control when adopting spirit of salt production alkyl chloride in its reactor is greater than 109 ℃, thereby, improved the purity and the yield of reaction product haloalkane.When adopting Hydrogen bromide, the simple substance bromine for the Hydrogen bromide oxidation that prevents high density produces so can add red phosphorus in reactor, is reduced into Hydrogen bromide with simple substance bromine.

The present invention is further illustrated below in conjunction with embodiment and accompanying drawing.

Fig. 1 is reactor and device synoptic diagram.

In reactor 1, add haloid acid, on reactor 1, connect the rectifying washing column, in the rectifying washing column filler is housed, halogen hydracid enters in the post by the sparger 9 in valve 12, under meter 16 and the rectifying washing column 2 in the acid header tank 5, C1-4 alcohol in the alcohol header tank 6 is by valve 15, under meter 18 enters in the reactor 1, also can pack in the pure header tank 6 to be pre-mixed acid and the alcohol mixture that configures.In reactor 1, carry out the reaction of acid and alcohol, its reactant haloalkane, acid and water are evaporated to the gas rising and enter rectifying washing column 2, separate and washing, and enter condenser 3 from the top by pipeline and be condensed into liquid, enter separator 7 again, be water 21 on the upper strata of separator 7, squeeze into backwater header tank 4 through valve 13, pump 10, water in the backwater header tank 4 evenly sprays through the grid distributor 8 that valve 14, under meter 17 enter in the rectifying washing column 2, and lower floor is a haloalkane 22, emits through valve 14.Reactor 1 is put into oil bath 20 heating, the temperature that thermometer 19 is measured in the reactor 1.

The operating process of preparation C1-4 haloalkane is: place enough haloid acid and be heated to controlled temperature in reactor 1, in sour header tank 5, place haloid acid, in pure header tank 6, place C1-4 alcohol, the inlet amount of control alcohol is that haloid acid molal quantity in unit time (branch) reactor/charging alcohol mole number is greater than 1000, for example, haloid acid in the reactor 1 is 8 moles, then the quantity of per minute adding alcohol is less than 0.008 mole, and from sour header tank 5, join haloid acid in the rectifying washing column, should equate also to be 0.008 mole/minute with alcohol, equally, also haloid acid and C1-4 alcohol can be pre-mixed by 1: 1 mole number, then, be placed in the pure header tank 6, and with the mole number of the haloid acid mole number/alcohol in unit time (branch) reactor 1 greater than 1000 speed charging.

Embodiment 1

In reactor 1, add concentration greater than 32 moles of 46% hydrobromic acid solutions and a small amount of red phosphorus, C1-4 alcohol adopts ethanol, and with concentration greater than 1: 1 in molar ratio uniform mixing of 46% Hydrogen bromide, be positioned in the pure header tank 6, the heating oil bath 20, temperature is greater than 125 ℃ in the controlling reactor, the inlet amount of control acid, pure mixed solution is 0.0268 mole/minute, and mol ratio is 1200, and the haloalkane product is a monobromethane, content 99.0%, yield 93.0%.

Embodiment 2

C1-4 alcohol adopts n-propyl alcohol, control inlet amount=0.0278 mole/minute, and mol ratio is 1150/ minute, and all the other are with embodiment 1, and the product of its haloalkane is the 1-N-PROPYLE BROMIDE, content 99 1%, yield 95.1%, content of isomer is less than 0.5%.

Embodiment 3

C1-4 alcohol adopts Virahol, and all the other are with embodiment 1, and the product of its haloalkane is the 2-N-PROPYLE BROMIDE, content 99.2%, yield 95.2%.

Embodiment 4

Different with the feeding manner of embodiment 3, Virahol and Hydrogen bromide add from pure header tank 6 and sour header tank 5 respectively, control Virahol inlet amount=0.0267 mole/minute, its mol ratio is 1200/ minute, the mole number of hydrobromic charging equates with alcohol, the haloalkane product that obtains is the 2-N-PROPYLE BROMIDE, content 99.3%, yield 95.3%.

Embodiment 5C1-4 alcohol adopts propyl carbinol, control propyl carbinol inlet amount=0.0291 mole/minute, and its mol ratio is 1100/ minute, and all the other are with embodiment 1, and its haloalkane product is the 1-n-butyl bromide, and content is 98.6%, yield 95.0%, content of isomer is less than 0.5%.

Embodiment 6

Haloid acid adopts content greater than 20.3% hydrochloric acid solution, C1-4 alcohol adopts propyl carbinol, place content in the reactor 1 and be 20 moles of 20.3% spirit of salt, place by mole blended mixed solutions such as propyl carbinol and spirit of salt in the alcohol header tank 6, the temperature in the controlling reactor is greater than 109 ℃, controls propyl carbinol inlet amount=0.0148 mole/minute, its mol ratio is 1350/ minute, its haloalkane product is a 1-chlorobutane, and content is 98.5%, and yield is 90.0%.

Can draw from the result of the foregoing description, the content of its C1-4 haloalkane particularly content of bromoalkane is about 99%, and foreign body object content is less than 0.5%, and yield also can reach about 95%, and its purity improves a lot.

Claims

1, a kind of production method of C1-4 haloalkane, it be is characterized in that by the pure and mild haloid acid of C1-4 direct reaction in reactor: haloid acid and the C1-4 alcohol mol ratio in the unit time (branch) is greater than 1000 in the reactor; When the C1-4 haloalkane of producing was bromoalkane, the temperature of reaction in the reactor was greater than 125 ℃; During the production alkyl chloride, the temperature of reaction in the reactor is greater than 109 ℃.

2, the production method of C1-4 haloalkane according to claim 1 is characterized in that: should keep red phosphorus to exist when producing bromoalkane in the reactor.