CN109651214A - Floccule in a kind of two mercapto ethyl thioethers of removal improves product purity, the method for yield - Google Patents
Floccule in a kind of two mercapto ethyl thioethers of removal improves product purity, the method for yield Download PDFInfo
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- CN109651214A CN109651214A CN201811541931.7A CN201811541931A CN109651214A CN 109651214 A CN109651214 A CN 109651214A CN 201811541931 A CN201811541931 A CN 201811541931A CN 109651214 A CN109651214 A CN 109651214A
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- mercapto ethyl
- floccule
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C319/00—Preparation of thiols, sulfides, hydropolysulfides or polysulfides
- C07C319/14—Preparation of thiols, sulfides, hydropolysulfides or polysulfides of sulfides
- C07C319/20—Preparation of thiols, sulfides, hydropolysulfides or polysulfides of sulfides by reactions not involving the formation of sulfide groups
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C335/00—Thioureas, i.e. compounds containing any of the groups, the nitrogen atoms not being part of nitro or nitroso groups
- C07C335/30—Isothioureas
- C07C335/32—Isothioureas having sulfur atoms of isothiourea groups bound to acyclic carbon atoms
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Abstract
It is an object of the invention to develop amino hydrogen floccule in a kind of two mercapto ethyl thioether products of removal, product purity, the method for yield are improved.In two mercapto ethyl thioether synthesis processes, increases acidizing process by hydrochloric acid and amino hydrogen generation addition reaction and amino hydrogen is converted to salt, then obtain product through separation, washing, separation, rectifying etc..The reasonable washing of design, separation equipment, realize continuous water-washing process, improve operating environment, reduce labor intensity；Solve the problems, such as the stifled tower of floccule in subsequent distillation process.The advantage of this process is that production process smooth operation, realizing industrialized production；Improve the appearance of product, product is as clear as crystal, and product purity is increased to 99% or more by 95%；Yield is increased to 90% or more by 75%.
Description
Technical field
The invention belongs to organic chemical industry's production technical fields, and in particular to the Industrialized synthesis method of two mercapto ethyl thioethers and
Post-processing operation technique.
Background technique
With the development of the development of China's Aviation Industry, especially new architecture, to the adhesion strength of sealing material, ageing-resistant
Property, stability propose requirements at the higher level, have been unable to satisfy using the polysulfide rubber sealant that traditional polysulfide rubber cooperates as host agent
It is required that.By the polysulfide rubber of two mercapto ethyl thioethers modification, its viscosity is substantially reduced compared with traditional liquid polysulphide rubber, can
Preferably cooperation filler, reduces cost, while improving the ageing-resistant performance of material, and the use temperature of material is -55 DEG C~120
DEG C, it can reach 150 DEG C in short term, and have the characteristics that oil resistant, water-fast, resistance to leaching, filled up the resistance to fuel oil in China, refractory seals agent
China's aircraft integral tank sealant level is substantially improved in blank, provides reliable material guarantee for the development of new architecture.
The two mercapto ethyl thioether country as modifying agent do not have industrialized production, lean on import, therefore two mercapto ethyl sulphur always
The engineering production of ether directly affects the process of sealing agent research and development.About the synthesis of two mercapto ethyl thioethers, document and patent
There are many middle report, and Fujian Inst. of Matter Structure, Chinese Academy of Sciences Zhang Jianjun etc. uses Sn (edt), NaOH etc. for Material synthesis two
Mercapto ethyl thioether, this technical process very very complicated.External existing two mercaptos ethyl thioether synthesis uses high-temperature high-pressure craft, deposits
The problems such as equipment investment is big, complex process, safety in production require high and product quality and yield is low, high production cost.Mesh
Thiodiglycol and thiocarbamide generate thiuronium salt under preceding normal temperature and pressure, and the route for synthesizing two mercapto ethyl thioethers through alkaline hydrolysis is of greatest concern.
The process is simple, but deposit in the product containing floccule, product purity is low, product is not limpid；And due to floccule
In the presence of causing in subsequent vacuum distillation process, there is gambling tower phenomenon, industrial operation is difficult, and product yield is lower.It converges and reaches in Hubei
Development in science and technology Co., Ltd, which reaches the clouds etc., generates thiuronium salt using Thiodiglycol and thiocarbamide, synthesizes two mercapto ethyl thioethers through alkaline hydrolysis
Route, but the substances such as catalyst, phase transfer catalyst, antioxidant are added in reaction process, there are raw materials the more, reaction time
The problems such as long, product is easily decomposed.
The present invention increases acidizing process during two mercapto ethyl thioether engineering chemistry databases, is sent out by hydrochloric acid and amino hydrogen
Amino hydrogen is converted to salt by raw addition reaction.In lectotype selection, we are according to the density contrasts of compositions various in reaction solution, to setting
Standby material, shape carry out quite reasonable design.Using Φ 500X1000 transparent glass reactor, material can effectively be divided
From；When washing, allows water mouth under reactor to flow into, by the density contrast of compositions various in reaction solution, keep water bottom-up from upper
Mouth flows out naturally, comes into full contact with material, realizes the continuous operation of washing step；Simultaneously in water and material contact process,
The upper layer that floccule remaining in reaction solution is taken to product releases lower layer's product, effectively by floccule after washing qualification
It removes.
It is engineered test result to show using Φ 500X1000 transparent glass reactor and corresponding operating, obtained product
Yield, purity, in terms of obtain satisfied as a result, final products purity reaches 99% or more, yield reaches
90% or more, transparency fully meets the requirement of synthesis modification polysulfide rubber.While ensuring quality, operator is reduced
Operation difficulty and labor intensity.Two mercapto ethyl thioethers of industrialized production are successfully used for aircraft and are ground with sealing agent at present
In project processed.
Summary of the invention
It is an object of the invention to develop amino hydrogen floccule in a kind of two mercapto ethyl thioether products of removal, product is improved
Purity, the method for yield.In two mercapto ethyl thioether synthesis processes, increases acidizing process by hydrochloric acid and amino hydrogen and addition occurs
Amino hydrogen is converted to salt by reaction, then obtains product through separation, washing, separation, rectifying etc..The reasonable washing of design, separation equipment,
It realizes continuous water-washing process, improves operating environment, reduce labor intensity；The stifled tower for solving floccule in subsequent distillation process is asked
Topic.The advantage of this process is that production process smooth operation, realizing industrialized production；Improve the appearance of product, product is limpid
Bright, product purity is increased to 99% or more by 95%；Yield is increased to 90% or more by 75%.
The invention discloses amino hydrogen floccules in a kind of two mercapto ethyl thioether products of removal, improve product purity, yield
Method.
Thiodiglycol of the present invention, thiocarbamide synthesize the molecular proportion of Thiodiglycol and hydrochloric acid in thiuronium salt reaction with hydrochloric acid
1:2.2 reacts 1 hour under room temperature；The molecular proportion of Thiodiglycol and thiocarbamide is 1:2.1, is reacted 2 hours at 80 DEG C.Alkaline hydrolysis
In reaction, use ammonium hydroxide for alkaline hydrolysis agent, the molecular proportion of Thiodiglycol and ammonium hydroxide is 1:2.2, at 85 DEG C, reacts 2 hours, obtains
Two mercapto ethyl thioether reaction solutions (I).
In two mercapto ethyl thioether reaction solution (I) acidification reactions of the invention, hydrochloric acid additional amount be make the pH value 3 of reaction solution~
6, it is advisable with 5.
In two mercapto ethyl thioether reaction solution (I) acidification reactions of the invention, reaction temperature is room temperature.
In two mercapto ethyl thioether reaction solution (I) acidification reactions of the invention, the reaction time is 0.5~2 hour, is with 1 hour
Preferably.
The present invention uses specific reactor such as attached drawing, and two mercapto ethyl thioether reaction solution sedimentation separations after acidification are come out
Afterwards, it allows water mouth under reactor to flow into, by the density contrast of compositions various in reaction solution, keeps water bottom-up and flowed naturally from suitable for reading
Out, it is come into full contact with material, realizes the continuous operation of washing step；Simultaneously in water and material contact process, by reaction solution
The floccule of middle remaining takes the upper layer of product to, after being washed to neutrality, releases lower layer's product i.e. two mercapto ethyl thioether crude products
(II), two mercapto ethyl thioether products are evaporated under reduced pressure to.
Steps are as follows for technical solution of the present invention:
Thiocarbamide, hydrochloric acid, Thiodiglycol by material ratio (molecular proportion of Thiodiglycol and hydrochloric acid be 1:1.5~2.5,
The molecular proportion of Thiodiglycol and thiocarbamide be 1:1.4~2.5) first by thiocarbamide, hydrochloric acid be added to equipped with blender, thermometer,
In the reactor of reflux condenser, normal-temperature reaction 1~2 hour, Thiodiglycol is added and is warming up to 70~110 DEG C, in this temperature
It is cooling after lower reaction 2~5 hours, the ammonium hydroxide (molecular proportion of Thiodiglycol and ammonium hydroxide is added into reactor by material ratio
For 1:1.5~3.0), be warming up to 70~90 DEG C, react at such a temperature cooling in 2~5 hours, at room temperature acid adding to pH value for 3~
It is static after 6, reaction 0.5~2 hour, it is obtained using the separation of specific reactor, by washing, separation, vacuum distillation colourless
Two bright mercapto ethyl thioethers.Its reaction principle is
Beneficial effect of the present invention is that two mercapto ethyl thioethers can be used as end group transforming agent, the modifying agent of sulfur-containing polymer,
It is also Aeronautics and Astronautics polysulfide for ether rubber and the primary raw material of modified polysulfide rubber.
Detailed description of the invention
Fig. 1 is treatment reactor, and 1 is feed inlet, and 2 be air inlet, and 3 be water inlet, and 4 be cage shoe, and 5 be discharge port, 6 for into
Water pipe.
Specific embodiment
The synthesis of two mercapto ethyl thioether reaction solutions (I):
253.2kg (32.5%) dense salt is packed into the 500L reaction kettle that blender, thermometer, reflux condenser are housed
Acid, 163.5kg thiocarbamide after normal-temperature reaction 1 hour, are added 125.0kg Thiodiglycol, are warming up to 80 DEG C, at this temperature instead
After answering 3 hours, 136.9kg ammonium hydroxide (28%) is added into reaction kettle, is warming up to 85 DEG C, reacts 2 hours, obtain at such a temperature
To two mercapto ethyl thioether reaction solutions (I).
Embodiment 1
By two mercapto ethyl thioether reaction solutions (I) be added to equipped with blender, thermometer, reflux condenser 500L reaction kettle
In, it is 5 that concentrated hydrochloric acid to pH value, which is added, after reacting 1 hour at normal temperature, stops stirring, static 1 hour, then specific anti-
It answers in device and is separated, retain subnatant；It is passed through water in the lower mouth of reactor, keeps water bottom-up and is flowed out naturally from suitable for reading, with
Material comes into full contact with, and floccule remaining in reaction solution is taken to the upper layer of product, after being washed to neutrality, releases lower layer's product
That is two mercapto ethyl thioether crude products (II), realize the continuous operation of washing step.It is evaporated under reduced pressure to colorless and transparent two mercaptos ethyl thioether
Product.Purity 99.3%, yield 91.8%.
Embodiment 2
By two mercapto ethyl thioether reaction solutions (I) be added to equipped with blender, thermometer, reflux condenser 500L reaction kettle
In, it is 3 that concentrated hydrochloric acid to pH value, which is added, after reacting 1 hour at normal temperature, stops stirring, static 1 hour, then specific anti-
It answers in device and is separated, retain subnatant；It is passed through water in the lower mouth of reactor, keeps water bottom-up and is flowed out naturally from suitable for reading, with
Material comes into full contact with, and floccule remaining in reaction solution is taken to the upper layer of product, after being washed to neutrality, releases lower layer's product
That is two mercapto ethyl thioether crude products (II), realize the continuous operation of washing step.It is evaporated under reduced pressure to colorless and transparent two mercaptos ethyl thioether
Product.Purity 98.4%, yield 89.1%.
Embodiment 3
By two mercapto ethyl thioether reaction solutions (I) be added to equipped with blender, thermometer, reflux condenser 500L reaction kettle
In, it is 6 that concentrated hydrochloric acid to pH value, which is added, after reacting 1 hour at normal temperature, stops stirring, static 1 hour, then specific anti-
It answers in device and is separated, retain subnatant；It is passed through water in the lower mouth of reactor, keeps water bottom-up and is flowed out naturally from suitable for reading, with
Material comes into full contact with, and floccule remaining in reaction solution is taken to the upper layer of product, after being washed to neutrality, releases lower layer's product
That is two mercapto ethyl thioether crude products (II), realize the continuous operation of washing step.It is evaporated under reduced pressure to colorless and transparent two mercaptos ethyl thioether
Product.Purity 98.4%, yield 90.1%.
Embodiment 4
By two mercapto ethyl thioether reaction solutions (I) be added to equipped with blender, thermometer, reflux condenser 500L reaction kettle
In, it is 5 that concentrated hydrochloric acid to pH value, which is added, after reacting 2 hours at normal temperature, stops stirring, static 1 hour, then specific anti-
It answers in device and is separated, retain subnatant；It is passed through water in the lower mouth of reactor, keeps water bottom-up and is flowed out naturally from suitable for reading, with
Material comes into full contact with, and floccule remaining in reaction solution is taken to the upper layer of product, after being washed to neutrality, releases lower layer's product
That is two mercapto ethyl thioether crude products (II), realize the continuous operation of washing step.It is evaporated under reduced pressure to colorless and transparent two mercaptos ethyl thioether
Product.Purity 99.2%, yield 90.8%.
Comparative example 1
Two mercapto ethyl thioether reaction solutions (I) are added in specific reactor and are separated, subnatant is retained, decompression is steamed
Evaporate to have two mercapto ethyl thioether products of floccule, purity 95.4%, yield 75.7%.
It is in comparative example to effectively remove without acidification washing step in place of embodiment 1 and 1 main difference of comparative example
As a result amino hydrogen floccule in reaction solution is substantially reduced compared with increase acidification, the yield of washing step, purity in embodiment, produces
Obviously with the presence of floccule in product.Illustrate the presence of amino hydrogen in reaction solution, first is that influencing appearance, the purity of product；Second is that because
There are problems that occurring in distillation process stifled tower for amino hydrogen, under identical vacuum, distillation kettle temperature is obviously higher, and product yield is low,
It even turns to be yellow, industrial operation is difficult.
Claims (10)
1. the method for amino hydrogen floccule in a kind of two mercapto ethyl thioethers of removal, which is characterized in that thiocarbamide, hydrochloric acid, thio two sweet
Alcohol be once added to equipped with blender, thermometer, reflux condenser reactor in, it is cooling after temperature reaction, add ammonia
Water carries out Basic fluxing raction, and two mercapto ethyl thioether reaction solutions are obtained after temperature reaction, two mercapto ethyl thioether reaction solutions are added to and are equipped with
Blender, thermometer, reflux condenser reaction kettle in, be added concentrated hydrochloric acid, at normal temperature react 1 hour after, stop stirring, it is quiet
It only 1 hour, is then separated in the reactor, retains subnatant；Water inlet pipe 6 is inserted into the water inlet 3 of reactor by water
It is passed through reactor bottom, keeps water bottom-up and is flowed out naturally from suitable for reading, come into full contact with material, it will be remaining cotton-shaped in reaction solution
Object takes the upper layer of product to, after being washed to neutrality, releases lower layer's product i.e. two mercapto ethyl thioether crude products, is evaporated under reduced pressure to colourless
Transparent two mercaptos ethyl thioether product.
2. the method for amino hydrogen floccule in two mercapto ethyl thioethers of removal according to claim 1, which is characterized in that thio
The molar ratio of diethylene glycol (DEG) and hydrochloric acid is 1:1.5~2.5；The molar ratio of Thiodiglycol and thiocarbamide is 1:1.4~2.5.
3. the method for amino hydrogen floccule in two mercapto ethyl thioethers of removal according to claim 2, which is characterized in that this hair
It is 1:2.2 that bright Thiodiglycol, thiocarbamide, which synthesize the molar ratio of Thiodiglycol and hydrochloric acid in different thiuronium salt reaction with hydrochloric acid,；It is thio
The molar ratio of diethylene glycol (DEG) and thiocarbamide is 1:2.1.
4. the method for amino hydrogen floccule in two mercapto ethyl thioethers of removal according to claim 1, which is characterized in that thio
Diethylene glycol (DEG), thiocarbamide and hydrochloric acid synthesis reaction temperature are 70~110 DEG C, and the reaction time is 2~5 hours.
5. the method for amino hydrogen floccule in two mercapto ethyl thioethers of removal according to claim 4, which is characterized in that reaction
Temperature is 80 DEG C, and the reaction time is 2 hours.
6. the method for amino hydrogen floccule in two mercapto ethyl thioethers of removal according to claim 1, which is characterized in that thio
The molar ratio of diethylene glycol (DEG) and ammonium hydroxide is 1:1.5~3.0, preferably 1:2.2.
7. the method for amino hydrogen floccule in two mercapto ethyl thioethers of removal according to claim 1, which is characterized in that alkaline hydrolysis
In reaction, reaction temperature is 70~90 DEG C, and the reaction time is 2~5 hours.
8. the method for amino hydrogen floccule in two mercapto ethyl thioethers of removal according to claim 7, which is characterized in that reaction
Temperature is 85 DEG C, and the reaction time is 2 hours.
9. the method for amino hydrogen floccule in two mercapto ethyl thioethers of removal according to claim 1, which is characterized in that dense salt
Sour additional amount is to make the pH value 3~6 of two mercapto ethyl thioether reaction solutions, preferably 5.
10. the method for amino hydrogen floccule in two mercapto ethyl thioethers of removal according to claim 1, it is characterised in that, institute
Stating reactor includes feed inlet 1, air inlet 2, water inlet 3, cage shoe 4, discharge port 5, water inlet pipe 6.
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