CN103319519B - A kind of method utilizing organic silicon azeotrope production hexamethyldisiloxane - Google Patents
A kind of method utilizing organic silicon azeotrope production hexamethyldisiloxane Download PDFInfo
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Abstract
The invention discloses a kind of method utilizing organic silicon azeotrope production hexamethyldisiloxane, comprising: (1) adds thermal distillation to organic silicon azeotrope, removing boiling point, lower than the cut of 40 DEG C, obtains intermediate blend; (2) described intermediate blend and ethanol are mixed into row intermittent esterification reaction, thermal distillation is added to reaction solution, collect boiling point lower than the cut of 80 DEG C, obtain trimethylchlorosilane crude product; (3) trimethylchlorosilane crude product is hydrolyzed, is separated from hydrolyzed solution and obtains hexamethyldisiloxane.The inventive method cost of material is cheap, ample supply and prompt delivery, and reaction process conditional gentleness, process stabilizing, continuous seepage efficiency are high, no coupling product; Without the need to using other poisonous and hazardous organic solvent, the hexamethyldisiloxane finished product purity of gained is more than 99%, and chloride ion content is less than 100ppm.
Description
Technical field
The present invention relates to the technical field of the by product recycling in chemical field organosilane monomer synthesis production, be specifically related to a kind of method utilizing organic silicon azeotrope production hexamethyldisiloxane.
Background technology
Mainly a class is with Si ~ O key for main chain for organosilicon material, and Si introduces the organic group macromolecular compound as side chain again, and its excellent performance, function are unique, are widely used in the fields such as military project, space flight, medical treatment, chemical industry, wherein (CH
3)
2siCl
2it is of paramount importance organosilane monomer.Directly synthesize the method for organochlorosilane under catalysis at copper powder from nineteen forty-one American Luo Qiao (US2380995) invention methyl chloride and silica flour since, methyl chlorosilane synthetic technology, through the development of over half a century, becomes better and approaching perfection day by day.China's silicone industry is through the development of recent two decades, and industrial scale also constantly expands, and just progressively moves to maturity.
Produce in methyl chlorosilane monomer industry in " direct method ", due to the restriction of the factor such as catalyzer, processing condition, except target product (CH in monomer crude product
3)
2siCl
2outward, silicon tetrachloride as by-product and trimethylchlorosilane are because boiling point is comparatively close to (being 57 DEG C), easy formation azeotrope, calculate by the production process route of current domestic methyl chlorosilane and level, general azeotrope massfraction is about 1 ~ 2wt% of monomer crude product.Industrial " azeotrope " composition obtained is generally: (CH
3)
3siCl is about 45 ~ 60wt%, SiCl
430 ~ 50wt%, other major ingredient is CH
3siHCl
2, HSiCl
3, (CH
3)
2the boiling points such as SiHCl, lower than 40 DEG C of mixtures, account for 5 ~ 10wt% of azeotrope composition.Along with the production-scale continuous expansion of China's methyl chlorosilane monomer in recent years, consequent azeotrope absolute quantity is also increasing rapidly.With the AOF calculation of current silicone industry in China monomer 2000kt/a.Calculate according to the ratio of 1 ~ 2wt%, the absolute quantity of national organosilane monomer enterprise low-boiling-point substance is about 20 ~ 40kt/a; As trans-utilization in addition not in time, great safety, environmental protection hidden danger will be caused.
Can not by " azeotrope " separately with common rectificating method, in addition, trimethylchlorosilane and silicon tetrachloride are all valuable silicoorganic compound, of many uses.Trimethylchlorosilane is the raw material in short supply preparing dimethyl silicone oil, silicon rubber, medical protective material and process White Carbon black.Tetraethoxy [Si (OC can be obtained after silicon tetrachloride esterification
2h
5)
4] be the important source material of producing the products such as silicone resin, room temperature silicon rubber, paint, coating, White Carbon black.Therefore, the isolation technique of research organosilane monomer by-product " azeotrope ", produce for " three wastes " reducing organosilane monomer manufacture, the resource circulation utilization etc. realizing by product has great significance.
The method of traditional separating azeotrope has physical method and chemical process.Physical method in azeotrope, adds another kind of material form new azeotropic and be separated, such as, CN1092778A discloses a kind of method adding dimethyl dichlorosilane (DMCS) and carry out being separated in azeotrope still-process, owing to inherently containing a small amount of methyl hydrogen dichlorosilane in azeotrope, therefore this method not only rectification step is loaded down with trivial details, energy consumption is high, and product trimethylchlorosilane, silicon tetrachloride purity are not high.US4402796 discloses a kind of solvent extraction of tetramethylene sulfone and utilizes a kind of auxiliary agent to carry out the method for extractive distillation to azeotrope; The method that US2388575 discloses and utilizes acetonitrile, vinyl cyanide equal solvent carries out extractive distillation.The shortcoming of these class methods is strict to azeotrope composition requirement, and silane compound to be separated is easily stain by other material, causes rectifying purification step too much.The solvent toxicity that this method is used is in addition large, and not easily reclaim, rectification efficiency is low.
Chemical process is separated after one or both in azeotrope are transformed again.The chlorine that US2381139 discloses on the silicon chlorine key in a kind of oxyethane and azeotrope reacts, and obtains 2 ~ chloroethoxy silane, then product is carried out rectifying separation purifying.This method advantage is, produces in reaction without gas.Shortcoming is gaseous state under oxyethane normal temperature used, and storage transport is very inconvenient, and price is more expensive.(the CH generated in addition
3)
3siOCH
2cH
2cl and Si (OCH
2cH
2cl)
4, can not find rational utilization ways.GB670476A discloses one and utilizes chlorosilane in phenol and azeotrope to react to generate (CH
3)
3siOC
6h
5with Si (C
6h
5)
4, then by (CH
3)
3siOC
6h
5hydrolysis preparation hexamethyldisiloxane, by product Si (C in this method
6h
5)
4substantially without market purposes, and in reaction, a large amount of phenolic wastewater environmental pollution produced is very large.Because the past " direct method " produces methyl chlorosilane technique comparatively backwardness, in azeotrope, be rich in the serial impurity such as METHYL TRICHLORO SILANE, dimethyldichlorosilane(DMCS), and this invention does not relate to preparation and the purification of hexamethyldisiloxane.
US2519926 and CN102924493 discloses the method for a kind of azeotrope hydrolysis, the method mainly controls trimethylchlorosilane hydrolysis rate at a certain temperature, use dimethylbenzene as solvent simultaneously, make trimethylchlorosilane and hydrolyzing silicon tetrachloride product by separation of oil, thus obtain hexamethyldisiloxane, prestox cyclosiloxane or silicon-dioxide or silicic acid.This method due to high boiling solvents such as needs dimethylbenzene, therefore adds serial post-processing step, and technique is loaded down with trivial details.Disclose in US2449815 and utilize HF or ZnF
2change into the separation method of silicon fluoride, this method requires higher to appliance arrangement, is unsuitable for applying.
CN101362777 discloses a kind of preparation method of hexamethyldisiloxane, the method with nontoxic carbonate for solid-phase reactant, be liquid phase reaction thing with tri-methyl-chlorosilane, take hexamethyldisiloxane as reaction solvent, synthesize hexamethyldisiloxane by liquid-solid reaction.CN102617625A discloses a kind of preparation method of high-quality hexamethyldisiloxane, this method first tri-methyl-chlorosilane is added drop-wise in water the reaction that is hydrolyzed, after having reacted, isolate lower floor's concentrated acid water, again upper oil phase washed, filter, obtain thick product, last rectifying obtains high-quality hexamethyldisiloxane.
Summary of the invention
The invention provides a kind of method utilizing organic silicon azeotrope production hexamethyldisiloxane, the method effectively can solve " direct method " and produce by product trimethylchlorosilane ~ tetrachloro silicane of producing in dimethyldichlorosilane(DMCS) process ~ containing the recycling problem of silicon hydride chlorid azeotrope.
Utilize a method for organic silicon azeotrope production hexamethyldisiloxane, comprising:
(1) add thermal distillation to organic silicon azeotrope, removing boiling point, lower than the cut of 40 DEG C, obtains intermediate blend;
Organic silicon azeotrope of the present invention refers to that " direct method " produces the azeotrope of methyl chlorosilane monomer generation, consists of: (CH
3)
3siCl(45 ~ 60wt%), SiCl
4(35 ~ 45wt%) and comprise CH
3siHCl
2, HSiCl
3, (CH
3)
2the boiling points such as SiHCl, lower than the hydrogeneous chlorosilane mixture (5 ~ 10wt%) of 40 DEG C, because of containing the as easy as rolling off a log generation polycondensation of silicon hydride chlorid alcoholysis product, generate siloxane oligomer, need be separated removal in advance.
(2) mixed with ethanol by described intermediate blend and carry out esterification, reaction terminates to add thermal distillation to reaction solution, collects boiling point lower than the cut of 80 DEG C, obtains trimethylchlorosilane crude product; By-product HCl gas absorption is 25wt% ~ 30wt% hydrochloric acid.
This process is silicon tetrachloride and ethanol generation esterification mainly, and trimethylchlorosilane participates in reaction on a small quantity, specific as follows:
SiCl
4+nC
2H
5OH→(C
2H
5O)
nSiCl
4-n+nHCl↑
(CH
3)
3SiCl+C
2H
5OH→(CH
3)
3Si(OC
2H
5)+HCl↑
Wherein, n=1 ~ 4.
Due to heat release strong in esterification reaction process, if produce a large amount of HCl gas simultaneously, easily cause loss of material, preferably adopt the ethanol interval mode be added drop-wise in intermediate blend to react, be specially:
At 20 ~ 30 DEG C, first the ethanol of 1/3 ~ 1/2 is added dropwise in intermediate blend with 200 ~ 300L/h, in 40 ~ 45 DEG C of back flow reaction 1 ~ 2 hour after dropwising, then at 40 ~ 45 DEG C, again the ethanol of 1/2 ~ 2/3 is added dropwise in reaction solution with 250 ~ 350L/h, after dropwising, is warmed up to 50 ~ 55 DEG C of back flow reaction 2 ~ 4 hours.
Most preferably be:
At 30 DEG C, first the ethanol of 1/3 is added dropwise in intermediate blend with 250L/h, in 40 DEG C of back flow reaction 1 hour after dropwising, then at 40 DEG C, again the ethanol of 2/3 is added dropwise in partial esterification reaction solution with 300L/h, after dropwising, is warmed up to 50 DEG C of back flow reaction 4 hours.
In esterification by-product HCl gas overflowing after be absorbed as 25wt% ~ 30wt% hydrochloric acid.Most of trimethylchlorosilane has neither part nor lot in reaction in addition, and the boiling point of it and trimethylmethoxysilane, all lower than 80 DEG C, can be separated by distillation mode.
(3) trimethylchlorosilane crude product is hydrolyzed, is separated from hydrolyzed solution and obtains hexamethyldisiloxane.
Trimethylchlorosilane hydrolysis generates hexamethyldisiloxane and hydrochloric acid, hexamethyldisiloxane is water insoluble, can be separated by stratification from hydrolyzed solution, because the oil phase be separated contains partial impurities, need by rectified purified, improve purity and reduce chloride ion content.
Preferably, hydrolysis temperature 10 ~ 50 DEG C, hydrolysis time is 4 ~ 10 hours.
Described separation and purification can be selected as under type:
In hydrolyzed solution, add aqueous sodium carbonate or sodium ethylate, be neutralized to pH value for neutral, oil phase is got in layering, carries out rectifying to oil phase, obtains hexamethyldisiloxane.
Described aqueous sodium carbonate massfraction is 20 ~ 30%.
The tower top temperature of described rectifying is 95 ~ 100 DEG C.
The inventive method cost of material is cheap, ample supply and prompt delivery, and reaction process conditional gentleness, process stabilizing, continuous seepage efficiency are high, no coupling product; Without the need to using other poisonous and hazardous organic solvent etc.The hexamethyldisiloxane product yield of gained is high, and finished product purity is more than 99%, and chloride ion content is less than 100ppm.
Embodiment
Organic azeotrope composition and content methyl chlorosilane monomer manufacture used in following embodiment adopt gas chromatogram fixative analysis.
The purity of the industrial alcohol adopted in following embodiment is 98%; Vapor-phase chromatography is adopted to carry out purity check to hexamethyldisiloxane finished product; Oxygen bottle combustion pre-treatment+ion chromatography is adopted to measure the total chloridion content in hexamethyldisiloxane finished product.
In following embodiment, step (3) about the calculation formula of mixture yield is:
Mixture quality × 100%/intermediate blend the quality of mixture yield=collection.
Calculation formula about hexamethyldisiloxane yield in step (5) in following embodiment is:
Hexamethyldisiloxane quality × 100% that hexamethyldisiloxane yield=rectifying obtains/intermediate blend quality.
Comparative example:
(1) by-product azeotrope [(CH in industrial organosilane monomer methyl chlorosilane being produced
3)
3siCl:49.57wt%, SiCl
4: 42.78wt%, CH
3siHCl
2: 4.64wt%, HSiCl
3: 1.31wt%, (CH
3)
2siHCl:1.67wt%] join in the autoclave device of band packing tower and carry out adding thermal distillation, controlling bottom temperature is 70 ~ 80 DEG C, tower top temperature is 38 ~ 42 DEG C, isolate the boiling points such as methyl hydrogen dichlorosilane, trichlorosilane and dimethyl silicane hydroxide lower than the light constituent of 40 DEG C, in still, obtain the intermediate blend of silicon tetrachloride and trimethylchlorosilane.
(2) step (1) gained intermediate blend is squeezed in reaction kettle of the esterification, ethanol is added drop-wise in reactor and carries out esterification; The rate of addition of ethanol is 300L/h, controlling temperature in reaction kettle of the esterification when ethanol drips is 30 DEG C, dropwise rear 55 DEG C of back flow reaction and obtain esterification reaction product in 4 hours, the mass ratio of ethanol and intermediate blend is 1.05:1, is absorbed as 25wt% ~ 30wt% hydrochloric acid after by-product HCl gas overflowing.
(3) distillation procedure is carried out to the esterification reaction product that step (2) obtains, less than the 80 DEG C cuts collected, be mainly trimethylchlorosilane and a small amount of trimethylmethoxysilane mixture, gained mixture yield is 46.8%, and bottoms is boiling point higher than the methoxychlor silane series high boiling material of 80 DEG C.
(4) trimethylchlorosilane step (3) obtained and a small amount of trimethylmethoxysilane mixture are hydrolyzed, and temperature during controlled hydrolysis is 25 DEG C, and hydrolysis time is 8 hours, and the mol ratio of water and mixture is 2.5:1.
(5) hydrolysis terminates to add sodium ethylate in backward hydrolysate and is neutralized to pH value for neutral (namely pH value is 7.0), in and time temperature be 75 DEG C, in be 5 hours with the time.
Carry out filtrations after neutralization terminates and remove solid impurity, then entering phase separator, to carry out profit settlement separate, obtains the thick finished product of hexamethyldisiloxane after removal bottom aqueous layer.
(6) the thick product of hexamethyldisiloxane of step (5) gained is carried out atmospheric distillation, control rectifying tower tower top temperature 95 ~ 100 DEG C, collecting the hexamethyldisiloxane yield obtained is 43.7%, and purity is 99.5%, and chloride ion content is 90ppm.
Embodiment 1:
(1) by-product azeotrope [(CH in industrial organosilane monomer methyl chlorosilane being produced
3)
3siCl:49.57wt%, SiCl
4: 42.78wt%, CH
3siHCl
2: 4.64wt%, HSiCl
3: 1.31wt%, (CH
3)
2siHCl:1.67wt%] join in the autoclave device of band packing tower and carry out adding thermal distillation, controlling bottom temperature is 70 ~ 80 DEG C, tower top temperature is 38 ~ 42 DEG C, isolate the boiling points such as methyl hydrogen dichlorosilane, trichlorosilane and dimethyl silicane hydroxide lower than the light constituent of 40 DEG C, in still, obtain the intermediate blend of silicon tetrachloride and trimethylchlorosilane.
(2) step (1) gained intermediate blend is squeezed in reaction kettle of the esterification, ethanol is added drop-wise in reactor by interval dropping mode and carries out esterification; At 25 DEG C, first the ethanol of 1/3 is added dropwise in intermediate blend with 200L/h, in 40 DEG C of back flow reaction 2 hours after dropwising, then at 40 DEG C, again the ethanol of 2/3 is added dropwise in partial esterification reaction solution with 350L/h, be warmed up to 55 DEG C of back flow reaction 3 hours after dropwising, the mass ratio of ethanol and intermediate blend is 1.05:1, is absorbed as 25wt% ~ 30wt% hydrochloric acid after by-product HCl gas overflowing.
(3) distillation procedure is carried out to the esterification reaction product that step (2) obtains, less than the 80 DEG C cuts collected, be mainly trimethylchlorosilane and a small amount of trimethylmethoxysilane mixture, gained mixture yield is 53.6%, and bottoms is boiling point higher than the methoxychlor silane series high boiling material of 80 DEG C.
(4) trimethylchlorosilane step (3) obtained and a small amount of trimethylmethoxysilane mixture are hydrolyzed, and temperature during controlled hydrolysis is 25 DEG C, and hydrolysis time is 8 hours, and the mol ratio of water and mixture is 2.5:1.
(5) hydrolysis terminates to add sodium ethylate in backward hydrolysate and is neutralized to pH value for neutral (namely pH value is 7.0), in and time temperature be 75 DEG C, in be 5 hours with the time.
Carry out filtrations after neutralization terminates and remove solid impurity, then entering phase separator, to carry out profit settlement separate, obtains the thick finished product of hexamethyldisiloxane after removal bottom aqueous layer.
(6) the thick product of hexamethyldisiloxane of step (5) gained is carried out atmospheric distillation, control rectifying tower tower top temperature 95 ~ 100 DEG C, collecting the hexamethyldisiloxane yield obtained is 51.3%, and purity is 99.6%, and chloride ion content is 60ppm.
Embodiment 2
(1) by-product azeotrope [(CH in industrial organosilane monomer methyl chlorosilane being produced
3)
3siCl:49.57wt%, SiCl
4: 42.78wt%, CH
3siHCl
2: 4.64wt%, HSiCl
3: 1.31wt%, (CH
3)
2siHCl:1.67wt%] join in the autoclave device of band packing tower and carry out adding thermal distillation.Controlling bottom temperature is 70 ~ 80 DEG C, and tower top temperature is about 40 DEG C, isolates the boiling points such as methyl hydrogen dichlorosilane, trichlorosilane and dimethyl silicane hydroxide lower than the light constituent of 40 DEG C, obtains the intermediate blend of silicon tetrachloride and trimethylchlorosilane in still.
(2) step (1) gained intermediate blend is squeezed in reaction kettle of the esterification, ethanol is added drop-wise in reactor by interval dropping mode and carries out esterification; At 30 DEG C, first the ethanol of 1/2 is added dropwise in intermediate blend with 250L/h, in 45 DEG C of back flow reaction 2 hours after dropwising, then at 45 DEG C, again the ethanol of 1/2 is added dropwise in partial esterification reaction solution with 350L/h, be warmed up to 50 DEG C of back flow reaction 2 hours after dropwising, the mass ratio of ethanol and intermediate blend is 1.1:1, is absorbed as 25wt% ~ 30wt% hydrochloric acid after the HCl gas overflowing of by-product.
(3) distillation procedure is carried out to the esterification reaction product that step (2) obtains, less than the 80 DEG C cuts collected are mainly trimethylchlorosilane and a small amount of trimethylmethoxysilane mixture, gained mixture yield is 52.7%, and bottoms is boiling point higher than the methoxychlor silane series high boiling material of 80 DEG C.
(4) trimethylchlorosilane step (3) obtained and a small amount of trimethylmethoxysilane mixture are hydrolyzed, temperature during controlled hydrolysis is 35 DEG C, hydrolysis time is 6 hours, and the mol ratio of water and trimethylchlorosilane and a small amount of trimethylmethoxysilane mixture is 3.5:1.
(5) hydrolysis terminates to add sodium ethylate in backward hydrolysate and is neutralized to pH value for neutral (namely pH value is 7.0), in and time temperature be 80 DEG C, in be 4 hours with the time.
Carry out filtrations after neutralization terminates and remove solid impurity, then entering phase separator, to carry out profit settlement separate, obtains the thick finished product of hexamethyldisiloxane after removal bottom aqueous layer.
(6) the thick product of hexamethyldisiloxane of step (5) gained is carried out atmospheric distillation, control rectifying tower tower top temperature 95 ~ 100 DEG C, collecting the hexamethyldisiloxane yield obtained is 51.3%, and purity is 99.7%, and chloride ion content is 60ppm.
Embodiment 3
(1) by-product azeotrope [(CH in industrial organosilane monomer methyl chlorosilane being produced
3)
3siCl:48.36wt%, SiCl
4: 43.63wt%, CH
3siHCl
2: 4.97wt%, HSiCl
3: 1.26wt%, (CH
3)
2siHCl:1.63wt%] join in the autoclave device of band packing tower and carry out adding thermal distillation.Controlling bottom temperature is 70 ~ 80 DEG C, and tower top temperature is about 40 DEG C, isolates the boiling points such as methyl hydrogen dichlorosilane, trichlorosilane and dimethyl silicane hydroxide lower than the light constituent of 40 DEG C, obtains the intermediate blend of silicon tetrachloride and trimethylchlorosilane in still.
(2) step (1) gained intermediate blend is squeezed in reaction kettle of the esterification, ethanol is added drop-wise in reactor by interval dropping mode and carries out esterification; At 25 DEG C, first the ethanol of 1/2 is added dropwise in intermediate blend with 250L/h, in 40 DEG C of back flow reaction 2 hours after dropwising, then at 40 DEG C, again the ethanol of 1/2 is added dropwise in partial esterification reaction solution with 300L/h, be warmed up to 50 DEG C of back flow reaction 2 hours after dropwising, the mass ratio of ethanol and intermediate blend is 1.2:1, is absorbed as 25wt% ~ 30wt% hydrochloric acid after the HCl gas overflowing of by-product.
(3) distillation procedure is carried out to the esterification reaction product that step (2) obtains, less than the 80 DEG C cuts collected are mainly trimethylchlorosilane and a small amount of trimethylmethoxysilane mixture, isolate methoxychlor silane series high boiling material, gained mixture yield is 51.9%, and bottoms is boiling point higher than the methoxychlor silane series high boiling material of 80 DEG C.
(4) trimethylchlorosilane step (3) obtained and a small amount of trimethylmethoxysilane mixture are hydrolyzed, temperature during controlled hydrolysis is 25 DEG C, hydrolysis time is 8 hours, and the mol ratio of water and trimethylchlorosilane and a small amount of trimethylmethoxysilane mixture is 4:1.
(5) hydrolysis terminates to add sodium ethylate in backward hydrolysate and is neutralized to pH value for neutral (namely pH value is 7.0), in and time temperature be 70 DEG C, in be 6 hours with the time.
Carry out filtrations after neutralization terminates and remove solid impurity, then entering phase separator, to carry out profit settlement separate, obtains the thick finished product of hexamethyldisiloxane after removal bottom aqueous layer.
(6) the thick product of hexamethyldisiloxane of step (5) gained is carried out atmospheric distillation, control rectifying tower tower top temperature 95 ~ 100 DEG C, collecting the hexamethyldisiloxane yield obtained is 50.6%, and purity is 99.8%, and chloride ion content is 50ppm.
Embodiment 4
(1) by-product azeotrope [(CH in industrial organosilane monomer methyl chlorosilane being produced
3)
3siCl:53.41wt%, SiCl
4: 38.59wt%, CH
3siHCl
2: 5.37wt%, HSiCl
3: 1.31wt%, (CH
3)
2siHCl:1.16wt%] join in the autoclave device of band packing tower and carry out adding thermal distillation.Controlling bottom temperature is 75 DEG C, and tower top temperature is about 40 DEG C, isolates the boiling points such as methyl hydrogen dichlorosilane, trichlorosilane and dimethyl silicane hydroxide lower than the light constituent of 40 DEG C, obtains the intermediate blend of silicon tetrachloride and trimethylchlorosilane in still.
(2) step (1) gained intermediate blend is squeezed in reaction kettle of the esterification, ethanol is added drop-wise in reactor by interval dropping mode and carries out esterification; At 30 DEG C, first the ethanol of 1/3 is added dropwise in intermediate blend with 250L/h, in 40 DEG C of back flow reaction 1 hour after dropwising, then at 40 DEG C, again the ethanol of 2/3 is added dropwise in partial esterification reaction solution with 300L/h, be warmed up to 50 DEG C of back flow reaction 4 hours after dropwising, the mass ratio of ethanol and intermediate blend is 1.15:1, is absorbed as 25wt% ~ 30wt% hydrochloric acid after the HCl gas overflowing of by-product.
(3) distillation procedure is carried out to the esterification reaction product that step (2) obtains, less than the 80 DEG C cuts collected are mainly trimethylchlorosilane and a small amount of trimethylmethoxysilane mixture, isolate methoxychlor silane series high boiling material, gained mixture yield is 59.3%, and bottoms is boiling point higher than the methoxychlor silane series high boiling material of 80 DEG C.
(4) trimethylchlorosilane step (3) obtained and a small amount of trimethylmethoxysilane mixture are hydrolyzed, temperature during controlled hydrolysis is 30 DEG C, hydrolysis time is 8 hours, and the mol ratio of water and trimethylchlorosilane and a small amount of trimethylmethoxysilane mixture is 3:1.
(5) hydrolysis terminates to add sodium ethylate in backward hydrolysate and is neutralized to pH value for neutral (namely pH value is 7.0), in and time temperature be 75 DEG C, in be 5 hours with the time.
Carry out filtrations after neutralization terminates and remove solid impurity, then entering phase separator, to carry out profit settlement separate, obtains the thick finished product of hexamethyldisiloxane after removal bottom aqueous layer.
(6) the thick product of hexamethyldisiloxane of step (5) gained is carried out atmospheric distillation, control rectifying tower tower top temperature 95 ~ 100 DEG C, collecting the hexamethyldisiloxane yield obtained is 55.4%, and purity is 99.3%, and chloride ion content is 60ppm.
Embodiment 5
(1) by-product azeotrope [(CH in industrial organosilane monomer methyl chlorosilane being produced
3)
3siCl:50.12wt%, SiCl
4: 40.76wt%, CH
3siHCl
2: 6.37wt%, HSiCl
3: 1.31wt%, (CH
3)
2siHCl:1.43wt%] join in the autoclave device of band packing tower and carry out adding thermal distillation.Controlling bottom temperature is 77 DEG C, and tower top temperature is about 40 DEG C, isolates the boiling points such as methyl hydrogen dichlorosilane, trichlorosilane and dimethyl silicane hydroxide lower than the light constituent of 40 DEG C, obtains the intermediate blend of silicon tetrachloride and trimethylchlorosilane in still.
(2) step (1) gained intermediate blend is squeezed in reaction kettle of the esterification, ethanol is added drop-wise in reactor by interval dropping mode and carries out esterification; At 30 DEG C, first the ethanol of 1/3 is added dropwise in intermediate blend with 250L/h, in 45 DEG C of back flow reaction 2 hours after dropwising, then at 45 DEG C, again the ethanol of 2/3 is added dropwise in partial esterification reaction solution with 350L/h, be warmed up to 50 DEG C of back flow reaction 2.5 hours after dropwising, the mass ratio of ethanol and intermediate blend is 1.2:1, is absorbed as 25wt% ~ 30wt% hydrochloric acid after the HCl gas overflowing of by-product.
(3) distillation procedure is carried out to the esterification reaction product that step (2) obtains, less than the 80 DEG C cuts collected are mainly trimethylchlorosilane and a small amount of trimethylmethoxysilane mixture, isolate methoxychlor silane series high boiling material, gained mixture yield is 55.6%, and bottoms is boiling point higher than the methoxychlor silane series high boiling material of 80 DEG C.
(4) trimethylchlorosilane step (3) obtained and a small amount of trimethylmethoxysilane mixture are hydrolyzed, temperature during controlled hydrolysis is 35 DEG C, hydrolysis time is 7 hours, and the mol ratio of water and trimethylchlorosilane and a small amount of trimethylmethoxysilane mixture is 3.5:1.
(5) hydrolysis terminates to add sodium ethylate in backward hydrolysate and is neutralized to pH value for neutral (namely pH value is 7.0), in and time temperature be 75 DEG C, in be 6 hours with the time.
Carry out filtrations after neutralization terminates and remove solid impurity, then entering phase separator, to carry out profit settlement separate, obtains the thick finished product of hexamethyldisiloxane after removal bottom aqueous layer.
(6) the thick product of hexamethyldisiloxane of step (5) gained is carried out atmospheric distillation, control rectifying tower tower top temperature 95 ~ 100 DEG C, collecting the hexamethyldisiloxane yield obtained is 53.7%, and purity is 99.5%, and chloride ion content is 70ppm.
Collecting the hexamethyldisiloxane purity obtained is 99.5%, and chloride ion content is 53ppm.
Claims (7)
1. utilize a method for organic silicon azeotrope production hexamethyldisiloxane, comprising:
(1) add thermal distillation to organic silicon azeotrope, removing boiling point, lower than the cut of 40 DEG C, obtains intermediate blend;
(2) described intermediate blend is mixed with ethanol carry out esterification, thermal distillation is added to reaction solution, collect boiling point lower than the cut of 80 DEG C, obtain trimethylchlorosilane crude product;
Described esterification is:
At 20 ~ 30 DEG C, first the ethanol of 1/3 ~ 1/2 is added dropwise in intermediate blend with 200 ~ 300L/h, in 40 ~ 45 DEG C of back flow reaction 1 ~ 2 hour after dropwising, then at 40 ~ 45 DEG C, again the ethanol of 1/2 ~ 2/3 is added dropwise in reaction solution with 250 ~ 350L/h, after dropwising, is warmed up to 50 ~ 55 DEG C of back flow reaction 2 ~ 4 hours;
(3) trimethylchlorosilane crude product is hydrolyzed, is separated from hydrolyzed solution and obtains hexamethyldisiloxane.
2. the method for claim 1, is characterized in that, in step (2), the mass ratio of described intermediate blend and ethanol is 0.9 ~ 1.3:1.
3. method as claimed in claim 2, it is characterized in that, in step (2), the mass ratio of described intermediate blend and ethanol is 1.0 ~ 1.2:1.
4. the method for claim 1, is characterized in that, in step (3), hydrolysis temperature 10 ~ 50 DEG C, hydrolysis time is 4 ~ 10 hours.
5. the method for claim 1, is characterized in that, in step (3), described in be separated into:
In hydrolyzed solution, add aqueous sodium carbonate or sodium ethylate, be neutralized to pH value for neutral, oil phase is got in layering, carries out rectifying to oil phase, obtains hexamethyldisiloxane.
6. method as claimed in claim 5, it is characterized in that, described aqueous sodium carbonate massfraction is 20 ~ 30%.
7. method as claimed in claim 5, it is characterized in that, the tower top temperature of described rectifying is 95 ~ 100 DEG C.
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| CN111004267A (en) * | 2019-12-13 | 2020-04-14 | 杭州崇耀科技发展有限公司 | Preparation method of hexamethyldisiloxane |
| CN111606938A (en) * | 2020-05-27 | 2020-09-01 | 江西蓝星星火有机硅有限公司 | Method and device for comprehensively utilizing organic silicon monomer azeotrope by utilizing alcoholysis process |
| CN113292592B (en) * | 2021-06-08 | 2023-02-03 | 天津大学 | Method for removing impurities of methyldichlorosilane and silicon tetrachloride in trimethylchlorosilane |
| CN113617061B (en) * | 2021-07-27 | 2022-12-27 | 合盛硅业(鄯善)有限公司 | Method for treating methyl chlorosilane hydrolysis emulsion |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2519926A (en) * | 1947-03-25 | 1950-08-22 | Gen Electric | Resolution of chlorosilane mixtures |
| CN102617625A (en) * | 2012-03-09 | 2012-08-01 | 山东东岳有机硅材料有限公司 | Preparation method for high-quality hexamethyldisiloxane |
| CN102924493A (en) * | 2012-11-05 | 2013-02-13 | 安徽九天硅业有限公司 | Method for preparing hexamethyldisiloxane through separation of organosilicon azeotrope |
-
2013
- 2013-05-31 CN CN201310214407.XA patent/CN103319519B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2519926A (en) * | 1947-03-25 | 1950-08-22 | Gen Electric | Resolution of chlorosilane mixtures |
| CN102617625A (en) * | 2012-03-09 | 2012-08-01 | 山东东岳有机硅材料有限公司 | Preparation method for high-quality hexamethyldisiloxane |
| CN102924493A (en) * | 2012-11-05 | 2013-02-13 | 安徽九天硅业有限公司 | Method for preparing hexamethyldisiloxane through separation of organosilicon azeotrope |
Non-Patent Citations (2)
| Title |
|---|
| (CH3)3SiCl-SiCl4共沸混合物酯化分离;张福民;《吉化科技》;19951231(第1期);第28-32页 * |
| 共沸物分离及深加工;王令湖等，;《有机硅材料》;20061231;第20卷(第2期);第75-77页，尤其是第75页第1.2节，第76页第2.1.1节 * |
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