Summary of the invention
The objective of the invention is at the deficiencies in the prior art, providing a kind of is the intermittently nitrated preparation 2 of Nitroanisole that raw material, technological process are simple, technical process is short with lower-cost Nitroanisole and composition thereof, 4-dinitrobenzene methyl ether technology.
The technical scheme that realizes above-mentioned purpose is: the intermittently nitrated preparation 2 of a kind of Nitroanisole, and 4-dinitrobenzene methyl ether technology, described processing step is as follows:
(1). nitration reaction is that intermittently nitration reaction takes place the nitration mixture that raw material and nitric acid and sulfuric acid mix with 4-Nitroanisole, 2-Nitroanisole, 4-Nitroanisole and 2-nitrobenzoyl ether mixture respectively;
(2). liquid liquid separates, and after nitration reaction finishes, carries out liquid liquid and separates, and water is the nitration mixture of intermediate concentration, is mainly 2 in the oil phase, and 4-dinitrobenzene methyl ether also has small amount of impurities and unreacted raw material;
(3). crystallisation by cooling, under 20 ℃~80 ℃ temperature, oil phase is carried out crystallisation by cooling, through solid-liquid separation, prepare 2,4-dinitrobenzene methyl ether crude product.
Further, the dehydration value of nitration mixture is controlled at 2.0~4.8 in the described the first step nitration reaction, and the mole proportioning of Nitroanisole and nitric acid is controlled at 1: 1.05~2.00, and the service temperature of nitration reaction is at 50 ℃~120 ℃.
Further, the isolating temperature of the described second step liquid liquid is controlled at 50 ℃~120 ℃.
Further, the solid-liquid separation temperature behind described the 3rd step crystallisation by cooling is controlled at 20 ℃~80 ℃.
Further, described nitration mixture is formed by 98% sulfuric acid, 95% nitric acid and the 65% nitric acid mixed preparing of technical grade.
Further, described nitration reaction is carried out in nitrator, and nitrator is the stirred-tank reactor that has heat-exchanger rig.
Further, described nitration reaction is carried out in nitrator, agitator in the nitrator is pusher impeller agitator, perhaps is hinged joint turbine type agitator, straight leaf disc formula turbine agitator, gear piece formula impeller agitator, flat leaf paddle agitator, crooked impeller-type stirrer.
Main chemical reactions formula of the present invention is:
Realize that the main technique equipment that the present invention needs is: stir nitrator, Crystallization Separation device and solid-liquid separator etc.
Reaction mechanism of the present invention is to adopt 2-Nitroanisole, 4-Nitroanisole and composition thereof to be raw material, generates 2,4-dinitrobenzene methyl ether.Because by the Location Mechanism of nitration reaction as can be known, on 2-Nitroanisole and 4-Nitroanisole phenyl ring-OCH
3Belong to the ortho para orientating group ,-NO
3Belong to meta-orienting group, these two orientating group orientation effect unanimities.Therefore, be reactant with 4-Nitroanisole, 2-Nitroanisole and 4-Nitroanisole and 2-nitrobenzoyl ether mixture, after the generation nitration reaction ,-NO
2Enter the position that they are determined jointly, promptly generate 2,4-dinitrobenzene methyl ether.In the nitrated generating process of 2-Nitroanisole, although 6 on the phenyl ring also are-OCH
3With-NO
3Co, but because 1-OCH
3With 2-NO
2Steric effect, so only may generate 2 of minute quantity, 6-dinitrobenzene methyl ether.In addition, 2, go up for 6 of 4-dinitrobenzene methyl ether phenyl ring nitration reaction further takes place, it is very difficult generating the 2 nitro.
Adopt the benefit of technique scheme to be: (1), cost are low.The present invention is to be that intermittently nitration reaction takes place the nitration mixture that raw material and nitric acid and sulfuric acid mix with 4-Nitroanisole, 2-Nitroanisole and 4-Nitroanisole and 2-nitrobenzoyl ether mixture, because Nitroanisole and mixture cost are lower, therefore prepare 2,4-dinitrobenzene methyl ether technology cost is low; (2), technology is simple, technical process is short.Technology of the present invention prepares 2 through nitration reaction, the separation of liquid liquid, crystallization separation process, 4-dinitrobenzene methyl ether crude product, and its technological process is simple, and technical process is short; (3), safety, reliability height.Because the whole technology of the present invention carries out at a lower temperature, cause the possibility of secondary pollution to descend greatly, so safety of the present invention, reliability height; (4) recyclable acid utilizes again.The present invention carries out liquid liquid and separates after nitration reaction takes place, and can carry out the recycling of acid to isolated water, this had both saved cost, has avoided the pollution of spent acid etc. again, very environmental protection.
Embodiment
The present invention is further detailed explanation below in conjunction with drawings and Examples.
Major equipment: stirred-tank reactor, Crystallization Separation device and the solid-liquid separator etc. that have heat-exchanger rig and pusher impeller agitator.
Embodiment one
The intermittently nitrated preparation 2 of a kind of Nitroanisole, 4-dinitrobenzene methyl ether technology, described processing step is as follows: in stirred-tank reactor, the 4-Nitroanisole is preheating to about 60 ℃, under agitation condition, nitration mixture under the room temperature is added drop-wise in the reactive system, nitration mixture is by 98% sulfuric acid of technical grade, 95% nitric acid and 65% nitric acid mixed preparing form, the dehydration value of nitration mixture is 4.2, the mole proportioning of Nitroanisole and nitric acid was controlled at 1.00: 1.05, control reaction temperature is at 65 ℃ ± 5 ℃, after dropwising, and heat temperature raising to 115 ℃ ± 5 ℃, constant temperature stirs 1.0h, leave standstill the layering of 1.0h liquid liquid then and separate, lower floor's water is a sulfuric acid, water and a spot of salpeter solution carry out can be recycled after the spent acid recycling; Upper oil phase is 2, and 4-dinitrobenzene methyl ether and a spot of 2 impurity and unreacted raw material 4-nitrobenzoyl ether mixture carry out Crystallization Separation.Be cooled to 60 ℃ of crystallizations, process suction filtration, prepare 2,4-dinitrobenzene methyl ether crude product.Obtain 2, conventional processing such as 4-dinitrobenzene methyl ether crude product can be washed, oven dry, can obtain lurid 2,4-dinitrobenzene methyl ether product.
Embodiment two
The intermittently nitrated preparation 2 of a kind of Nitroanisole, 4-dinitrobenzene methyl ether technology, described processing step is as follows: in stirred-tank reactor, the 2-Nitroanisole is heated to about 50 ℃, under agitation condition, nitration mixture under the room temperature is added drop-wise in the reactive system, nitration mixture is by 98% sulfuric acid of technical grade, 95% nitric acid and 65% nitric acid mixed preparing form, the dehydration value of nitration mixture is 4.7, the mole proportioning of Nitroanisole and nitric acid was controlled at 1.00: 1.10, control reaction temperature is at 70 ℃ ± 5 ℃, after dropwising, and heat temperature raising to 120 ℃ ± 5 ℃, constant temperature stirs 3.0h, leave standstill the layering of 1.0h liquid liquid then and separate, lower floor's water is a sulfuric acid, water and a spot of salpeter solution carry out can be recycled after the spent acid recycling; Upper oil phase is 2,4-dinitrobenzene methyl ether and a spot of 2, and 6-dinitrobenzene methyl ether and 2 impurity and unreacted raw material 2-Nitroanisole and 4-nitrobenzoyl ether mixture carry out Crystallization Separation.Be cooled to 30 ℃ of crystallizations, process suction filtration, prepare 2,4-dinitrobenzene methyl ether crude product.Obtain 2, conventional processing such as 4-dinitrobenzene methyl ether crude product can be washed, oven dry, can obtain lurid 2,4-dinitrobenzene methyl ether product.
Embodiment three
The intermittently nitrated preparation 2 of a kind of Nitroanisole, 4-dinitrobenzene methyl ether technology, described processing step is as follows: in stirred-tank reactor, 2-Nitroanisole and 4-nitrobenzoyl ether mixture are heated to about 60 ℃ as raw material, begin to add nitration mixture, nitration mixture is by 98% sulfuric acid of technical grade, 95% nitric acid and 65% nitric acid mixed preparing form, the dehydration value of nitration mixture is 2.8, and the mole proportioning of Nitroanisole and nitric acid was controlled at 1.00: 1.05, and temperature should maintain 55 ℃~75 ℃, after adding, continue to stir, when treating that temperature no longer rises, heat temperature raising degree to 120 ℃, and continue under 120 ℃ to stir 3.0h, two nitrated reactions can be finished.The layering of liquid liquid separates after leaving standstill 0.5h, and lower floor's water is sulfuric acid, water and a spot of salpeter solution, carries out can be recycled after the spent acid recycling; Upper oil phase is 2,4-dinitrobenzene methyl ether and a spot of 2, and 6-dinitrobenzene methyl ether and 2 impurity and unreacted raw material 2-Nitroanisole and 4-nitrobenzoyl ether mixture carry out Crystallization Separation.Be cooled to 60 ℃ of crystallizations, suction filtration while hot, prepare 2,4-dinitrobenzene methyl ether crude product.Filter cake conventional processing such as dries then with 70 ℃ of washings twice, can obtain lurid 2,4-dinitrobenzene methyl ether product.