CN113563376A - Method for recovering waste silicon rubber - Google Patents
Method for recovering waste silicon rubber Download PDFInfo
- Publication number
- CN113563376A CN113563376A CN202110776667.0A CN202110776667A CN113563376A CN 113563376 A CN113563376 A CN 113563376A CN 202110776667 A CN202110776667 A CN 202110776667A CN 113563376 A CN113563376 A CN 113563376A
- Authority
- CN
- China
- Prior art keywords
- waste
- silicon rubber
- dmc
- silicone rubber
- sulfuric acid
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 229920002379 silicone rubber Polymers 0.000 title claims abstract description 124
- 239000002699 waste material Substances 0.000 title claims abstract description 116
- 238000000034 method Methods 0.000 title claims abstract description 38
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims abstract description 86
- 239000000843 powder Substances 0.000 claims abstract description 42
- 239000004945 silicone rubber Substances 0.000 claims abstract description 35
- 239000012043 crude product Substances 0.000 claims abstract description 29
- 150000008044 alkali metal hydroxides Chemical class 0.000 claims abstract description 14
- 238000006462 rearrangement reaction Methods 0.000 claims abstract description 11
- 238000003756 stirring Methods 0.000 claims abstract description 11
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 9
- 238000002156 mixing Methods 0.000 claims abstract description 8
- 238000007873 sieving Methods 0.000 claims abstract description 8
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical group [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 30
- 239000002245 particle Substances 0.000 claims description 22
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 claims description 13
- 238000004064 recycling Methods 0.000 claims description 10
- 238000004140 cleaning Methods 0.000 claims description 6
- 238000001035 drying Methods 0.000 claims description 6
- 238000012691 depolymerization reaction Methods 0.000 claims description 5
- 238000005336 cracking Methods 0.000 abstract description 20
- 238000004523 catalytic cracking Methods 0.000 abstract description 16
- 239000002253 acid Substances 0.000 abstract description 13
- 230000000694 effects Effects 0.000 abstract description 8
- 230000003197 catalytic effect Effects 0.000 abstract description 6
- 230000008707 rearrangement Effects 0.000 abstract description 5
- 238000007171 acid catalysis Methods 0.000 abstract 1
- 238000004230 steam cracking Methods 0.000 abstract 1
- 239000000047 product Substances 0.000 description 11
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 8
- 239000000945 filler Substances 0.000 description 8
- 238000011084 recovery Methods 0.000 description 8
- 239000000126 substance Substances 0.000 description 7
- 238000005260 corrosion Methods 0.000 description 5
- 230000007797 corrosion Effects 0.000 description 5
- 238000006243 chemical reaction Methods 0.000 description 4
- 239000000377 silicon dioxide Substances 0.000 description 4
- 235000012239 silicon dioxide Nutrition 0.000 description 4
- 230000000052 comparative effect Effects 0.000 description 3
- 238000000227 grinding Methods 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 238000000053 physical method Methods 0.000 description 3
- 239000003153 chemical reaction reagent Substances 0.000 description 2
- 125000000118 dimethyl group Chemical group [H]C([H])([H])* 0.000 description 2
- 238000004821 distillation Methods 0.000 description 2
- 229920001971 elastomer Polymers 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 238000007781 pre-processing Methods 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 239000005060 rubber Substances 0.000 description 2
- -1 siloxane ring Chemical group 0.000 description 2
- 238000004227 thermal cracking Methods 0.000 description 2
- CBENFWSGALASAD-UHFFFAOYSA-N Ozone Chemical compound [O-][O+]=O CBENFWSGALASAD-UHFFFAOYSA-N 0.000 description 1
- 230000032683 aging Effects 0.000 description 1
- 230000008094 contradictory effect Effects 0.000 description 1
- KPUWHANPEXNPJT-UHFFFAOYSA-N disiloxane Chemical class [SiH3]O[SiH3] KPUWHANPEXNPJT-UHFFFAOYSA-N 0.000 description 1
- 239000000428 dust Substances 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 230000036541 health Effects 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 238000010298 pulverizing process Methods 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 229920003051 synthetic elastomer Polymers 0.000 description 1
- 239000005061 synthetic rubber Substances 0.000 description 1
- 239000004753 textile Substances 0.000 description 1
- 238000004073 vulcanization Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07F—ACYCLIC, CARBOCYCLIC OR HETEROCYCLIC COMPOUNDS CONTAINING ELEMENTS OTHER THAN CARBON, HYDROGEN, HALOGEN, OXYGEN, NITROGEN, SULFUR, SELENIUM OR TELLURIUM
- C07F7/00—Compounds containing elements of Groups 4 or 14 of the Periodic System
- C07F7/02—Silicon compounds
- C07F7/21—Cyclic compounds having at least one ring containing silicon, but no carbon in the ring
Abstract
The invention discloses a method for recovering waste silicon rubber, which comprises the following steps: s10, crushing and sieving the waste silicone rubber to obtain waste silicone rubber powder; s20, mixing waste silicon rubber powder and alkali metal hydroxide, and reacting under the conditions of water vapor at 120-160 ℃, inert atmosphere and high pressure of 3-5 MPa to obtain crude DMC; s30, stirring the crude product DMC and dilute sulfuric acid at 140-150 ℃ to perform depolymerization rearrangement reaction on the crude product DMC to obtain an intermediate; s40, rectifying the intermediate to obtain the purified DMC. Thus, the waste silicon rubber is catalytically cracked by using the dilute sulfuric acid, so that the corrosivity to equipment is reduced, and meanwhile, the catalytic activity of the dilute sulfuric acid is improved by placing the dilute sulfuric acid at the temperature of 140-150 ℃, so that the acid catalytic cracking effect is ensured; in addition, the waste silicon rubber powder is firstly subjected to steam cracking treatment to obtain a crude product DMC, then the crude product DMC is subjected to acid catalysis depolymerization rearrangement, and through two-step cracking, the cracking rate and the DMC yield are further improved.
Description
Technical Field
The invention relates to the technical field of silicon rubber products, in particular to a method for recovering waste silicon rubber.
Background
The silicone rubber is a synthetic rubber taking a silicon-oxygen bond as a main chain, has excellent heat resistance, cold resistance, dielectricity, ozone resistance and aging resistance, and is widely applied to the fields of aerospace, electronics and electricity, light industry, chemical industry, textile, machinery, building, agriculture, transportation, medical treatment and health care and the like. The silicon rubber products are mainly divided into three categories, namely high-temperature rubber, room-temperature rubber and liquid silicon rubber, and the application field is very wide. With the increasing consumption of silicon rubber products in the current society, waste silicon rubber products and leftover materials generated in vulcanization molding processing and waste silicon rubber formed after application are rapidly increasing, and if the waste silicon rubber products are not recycled, the waste silicon rubber products not only occupy space, but also waste resources and pollute the environment.
At present, the recovery methods of silicon rubber leftover materials and waste products mainly comprise two physical and chemical methods. The physical method is mainly characterized in that waste silicon rubber is crushed and then used as a filler, the method is simple and easy to operate, but dimethyl cyclosiloxane (DMC) and filler silicon dioxide contained in the silicon rubber are high in price and directly used as the filler without being recycled, so that the value of the filler cannot be fully utilized, and resources are wasted. The chemical method is mainly to recover and synthesize the organic siloxane ring body and the silicon dioxide which are used as raw materials of the silicon rubber by cracking. And the chemical cracking method includes thermal cracking, ultrasonic cracking, catalytic cracking, etc. At present, an acid catalytic cracking method is mainly adopted, but the acid catalytic cracking method has the problems of serious corrosion to equipment, need of regular replacement and high cost.
Disclosure of Invention
The invention mainly aims to provide a method for recovering waste silicon rubber, and aims to solve the problem that the existing acid catalytic cracking method has high corrosion to equipment.
In order to achieve the purpose, the invention provides a method for recovering waste silicone rubber, which comprises the following steps:
s10, crushing and sieving the pretreated waste silicone rubber to obtain waste silicone rubber powder;
s20, mixing the waste silicon rubber powder with alkali metal hydroxide, and reacting under the conditions of water vapor at 120-160 ℃, inert atmosphere and high pressure of 3-5 MPa to primarily crack the waste silicon rubber powder to obtain a crude product DMC;
s30, stirring the crude product DMC and the dilute sulfuric acid solution at 140-150 ℃ to enable the crude product DMC to undergo further depolymerization and rearrangement reaction to obtain an intermediate;
s40, rectifying the intermediate to obtain the refined DMC.
Optionally, in step S10, the preprocessing step includes:
and cleaning and drying the waste silicon rubber.
Optionally, step S10 includes:
carrying out primary crushing treatment on the pretreated waste silicon rubber to obtain waste silicon rubber particles;
and finely crushing the waste silicon rubber particles, and sieving the crushed waste silicon rubber particles with a 50-100-mesh sieve to obtain waste silicon rubber powder.
Optionally, in step S20, the mass ratio of the alkali metal hydroxide to the waste silicone rubber powder is (0.2-2): 100.
alternatively, in step S20, the alkali metal hydroxide is sodium hydroxide or potassium hydroxide.
Alternatively, in step S30:
in the dilute sulfuric acid solution, the mass fraction of the sulfuric acid is 50-65%.
Alternatively, in step S30:
the mass ratio of the crude DMC to the dilute sulfuric acid is 10: (0.1-0.5).
Alternatively, in step S30:
the stirring time is 120-180 min.
Alternatively, in step S40:
the temperature of the rectification treatment is 150-250 ℃.
According to the technical scheme provided by the invention, dilute sulfuric acid is adopted to carry out catalytic cracking on waste silicon rubber, so that the corrosivity of an acid catalytic cracking method on equipment is reduced, and meanwhile, the catalytic activity of the dilute sulfuric acid is improved by placing the dilute sulfuric acid at the temperature of 140-150 ℃, so that the effect of acid catalytic depolymerization rearrangement is ensured; in addition, the waste silicon rubber powder is cracked by using steam to obtain a crude product DMC, then the crude product DMC is subjected to further acid catalytic cracking rearrangement, and the cracking rate and the DMC yield are further improved through two-step cracking.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.
It should be noted that those whose specific conditions are not specified in the examples were performed according to the conventional conditions or the conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially. In addition, the meaning of "and/or" appearing throughout includes three juxtapositions, exemplified by "A and/or B" including either A or B or both A and B. In addition, technical solutions between various embodiments may be combined with each other, but must be realized by a person skilled in the art, and when the technical solutions are contradictory or cannot be realized, such a combination should not be considered to exist, and is not within the protection scope of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The recovery method of silicon rubber leftover materials and waste products mainly comprises a physical method and a chemical method. The physical method is mainly characterized in that waste silicon rubber is crushed and then used as a filler, the method is simple and easy to operate, but dimethyl cyclosiloxane (DMC) and filler silicon dioxide contained in the silicon rubber are high in price and directly used as the filler without being recycled, so that the value of the filler cannot be fully utilized, and resources are wasted. The chemical method is mainly to recover and synthesize the organic siloxane ring body and the silicon dioxide which are used as raw materials of the silicon rubber by cracking. And the chemical cracking method includes thermal cracking, ultrasonic cracking, catalytic cracking, etc. At present, an acid catalytic cracking method is mainly adopted, but the acid catalytic cracking method has the problems of serious corrosion to equipment, need of regular replacement and high cost.
In view of the above, the invention provides a method for recovering waste silicone rubber, and aims to provide a method for recovering waste silicone rubber, which has low corrosion to equipment and high DMC yield. In one embodiment, the recycling method comprises the steps of:
and step S10, crushing and sieving the pretreated waste silicone rubber to obtain waste silicone rubber powder.
Wherein the pre-processing step comprises: and cleaning and drying the waste silicon rubber. Therefore, dust, dirt and the like on the surface of the waste silicon rubber can be removed, so that other impurities are prevented from being brought in the recovery process, and the recovery effect is prevented from being influenced. The waste silicone rubber is not limited in source, and can be any waste silicone rubber product.
Further, in order to make the waste silicone rubber have a better pulverization effect and better react with water vapor or dilute sulfuric acid, so as to make the cracking effect better, in an embodiment, the step S10 includes:
and step S11, performing primary crushing treatment on the pretreated waste silicon rubber to obtain waste silicon rubber particles.
Wherein, the primary crushing can be carried out by any one of a crusher, a ball mill and an open mill to obtain granular waste silicon rubber.
And step S12, finely crushing the waste silicone rubber particles, and sieving the crushed waste silicone rubber particles through a 50-100-mesh sieve to obtain waste silicone rubber powder.
The present invention is not limited to the specific steps of the fine grinding, and the waste silicone rubber particles may be repeatedly ground by a crusher, a ball mill or an open mill to achieve the fine grinding, and in one embodiment, the fine grinding may be performed by a micronizer. And then, sieving the finely crushed waste silicon rubber particles by a sieve of 50-100 meshes to obtain waste silicon rubber powder with the particle size of 0.15-0.3 mm, so that the contact area of the waste silicon rubber powder with steam and dilute sulfuric acid is larger, and the cracking reaction is more sufficient.
Step S20, mixing the waste silicon rubber powder with alkali metal hydroxide, and reacting under the conditions of water vapor at 120-160 ℃, inert atmosphere and high pressure of 3-5 MPa to primarily crack the waste silicon rubber powder to obtain a crude product DMC.
In the high-pressure steam, the silicon-oxygen-silicon bonds of the waste silicone rubber can be broken to depolymerize into siloxane oligomers, and in this embodiment, the depolymerization reaction is made easier by the addition of alkali metal hydroxide.
The invention is not limited to the specific type of alkali metal hydroxide, and in one embodiment, the alkali metal hydroxide is sodium hydroxide (NaOH) or potassium hydroxide (KOH), which is readily available and low cost.
Further, in this embodiment, the mass ratio of the alkali metal hydroxide to the waste silicone rubber powder is (0.2-2): 100, a small amount of alkali metal hydroxide is added to ensure that the depolymerization effect of the waste silicon rubber powder is good, and meanwhile, the small amount of alkali metal hydroxide is not easy to cause potential safety hazards and has high operation safety.
And step S30, stirring the crude DMC and the dilute sulfuric acid solution at 140-150 ℃ to enable the crude DMC to undergo further depolymerization rearrangement reaction to obtain an intermediate.
In order to reduce the corrosivity of acid catalytic cracking on equipment, in this embodiment, a dilute sulfuric acid solution is used to perform a cracking rearrangement reaction on the crude DMC, and the catalytic activity of the dilute sulfuric acid is improved by a high temperature of 140-150 ℃. Further, in order to ensure the catalytic activity of the cracking rearrangement reaction and reduce the corrosion to the equipment, in this embodiment, the mass fraction of the sulfuric acid in the dilute sulfuric acid solution is 50-65%, and the dilute sulfuric acid can further catalyze the depolymerization of the macromolecular chains in the crude DMC and carry out the molecular rearrangement, so that more DMC can be recovered.
Wherein the stirring time is 120-180 min, so that the depolymerization rearrangement reaction can be fully performed. Furthermore, for the purpose of ensuring the effect of the cracking rearrangement reaction and saving the cost, in one embodiment, the mass ratio of the crude DMC to the dilute sulfuric acid is 10: (0.1-0.5).
And step S40, rectifying the intermediate to obtain the refined DMC.
Rectification is a separation process in which the components in a mixture are separated by virtue of their different volatilities, and the conventional equipment includes a plate-type rectification column and a packed rectification column. In this example, in order to separate DMC in the intermediate, a rectification treatment was performed under reduced pressure to separate purified DMC. Wherein the temperature of the rectification treatment is 150-250 ℃.
According to the technical scheme provided by the invention, dilute sulfuric acid is adopted to carry out catalytic cracking on waste silicon rubber, so that the corrosivity of an acid catalytic cracking method on equipment is reduced, and meanwhile, the catalytic activity of the dilute sulfuric acid is improved by placing the dilute sulfuric acid under a heating condition of 140-150 ℃, so that the acid catalytic cracking effect is ensured; in addition, the waste silicon rubber powder is cracked by using water vapor, then the crude product DMC obtained after primary cracking is further subjected to acid catalytic cracking rearrangement, through two-step cracking, the recovery rate of DMC can reach more than 92%, and meanwhile, the reaction condition of each step of cracking is mild, so that the time and the cost are saved.
The technical solutions of the present invention are further described in detail with reference to the following specific examples, which should be understood as merely illustrative and not limitative.
Example 1
(1) The waste silicon rubber after cleaning and drying is subjected to primary crushing treatment by a crusher to obtain waste silicon rubber particles, the waste silicon rubber particles are subjected to fine crushing by a superfine crusher and pass through a 80-mesh sieve to obtain waste silicon rubber powder.
(2) Mixing the waste silicon rubber powder with NaOH (wherein the mass ratio of the waste silicon rubber powder to the NaOH is 1:100), and reacting under the conditions of steam at 140 ℃, inert atmosphere and high pressure of 3.5MPa to preliminarily crack the waste silicon rubber powder to obtain a crude product DMC.
(3) And (3) stirring the crude product DMC and a dilute sulfuric acid solution (in the dilute sulfuric acid solution, the mass fraction of sulfuric acid is 50 percent, and the mass ratio of the crude product DMC to the dilute sulfuric acid solution is 10:0.3) at 150 ℃ for 150min to perform further depolymerization rearrangement reaction on the crude product DMC to obtain an intermediate.
(4) The intermediate was subjected to distillation under reduced pressure at 200 ℃ to obtain purified DMC, the yield of DMC was 93%.
Example 2
(1) The waste silicon rubber after cleaning and drying is subjected to primary crushing treatment by a ball mill to obtain waste silicon rubber particles, the waste silicon rubber particles are subjected to fine crushing by a superfine crusher and are sieved by a 50-mesh sieve to obtain waste silicon rubber powder.
(2) Mixing the waste silicon rubber powder with NaOH (wherein the mass ratio of the waste silicon rubber powder to the NaOH is 2:100), and reacting under the conditions of water vapor at 120 ℃, inert atmosphere and high pressure of 3MPa to preliminarily crack the waste silicon rubber powder to obtain a crude product DMC.
(3) And (2) stirring the crude product DMC and a dilute sulfuric acid solution (in the dilute sulfuric acid solution, the mass fraction of sulfuric acid is 60 percent, and the mass ratio of the crude product DMC to the dilute sulfuric acid solution is 10:0.1) at 140 ℃ for 180min to ensure that the crude product DMC is subjected to further depolymerization and rearrangement reaction to obtain an intermediate.
(4) The intermediate was subjected to distillation under reduced pressure at 150 ℃ to obtain purified DMC with a DMC yield of 92%.
Example 3
(1) The cleaned and dried waste silicon rubber is subjected to primary crushing treatment by an open mill to obtain waste silicon rubber particles, the waste silicon rubber particles are subjected to fine crushing by a superfine crusher and are sieved by a 100-mesh sieve to obtain waste silicon rubber powder.
(2) Mixing the waste silicon rubber powder with KOH (wherein the mass ratio of the waste silicon rubber powder to NaOH is 0.2:100), and reacting under the conditions of water vapor at 160 ℃, inert atmosphere and high pressure of 5MPa to preliminarily crack the waste silicon rubber powder to obtain a crude product DMC.
(3) And (3) stirring the crude product DMC and a dilute sulfuric acid solution (in the dilute sulfuric acid solution, the mass fraction of sulfuric acid is 65 percent, and the mass ratio of the crude product DMC to the dilute sulfuric acid solution is 10:0.5) at 145 ℃ for 120min to further perform depolymerization rearrangement reaction on the crude product DMC to obtain an intermediate.
(4) The intermediate was subjected to rectification treatment under reduced pressure at 250 ℃ to obtain purified DMC with a DMC yield of 95%.
Comparative example 1
(1) The cleaned and dried waste silicon rubber is subjected to primary crushing treatment by an open mill to obtain waste silicon rubber particles, the waste silicon rubber particles are subjected to fine crushing by a superfine crusher and are sieved by a 100-mesh sieve to obtain waste silicon rubber powder.
(2) Mixing the waste silicon rubber powder with KOH (wherein the mass ratio of the waste silicon rubber powder to NaOH is 0.2:100), and reacting under the conditions of water vapor at 160 ℃, inert atmosphere and high pressure of 5MPa to perform cracking reaction on the waste silicon rubber powder to obtain a crude product DMC.
(3) And (3) rectifying the crude DMC under reduced pressure at 250 ℃ to obtain refined DMC, wherein the yield of DMC is 40%.
Comparative example 2
(1) The waste silicon rubber after cleaning and drying is subjected to primary crushing treatment by a crusher to obtain waste silicon rubber particles, the waste silicon rubber particles are subjected to fine crushing by a superfine crusher and pass through a 80-mesh sieve to obtain waste silicon rubber powder.
(2) And (2) stirring the waste silicon rubber powder and a dilute sulfuric acid solution (in the dilute sulfuric acid solution, the mass fraction of sulfuric acid is 50 percent, and the mass ratio of the crude product DMC to the dilute sulfuric acid solution is 10:0.3) at 150 ℃ for 150min to ensure that the waste silicon rubber powder is subjected to depolymerization reaction to obtain the crude product DMC.
(3) And (3) rectifying the crude DMC under reduced pressure at 200 ℃ to obtain refined DMC, wherein the yield of DMC is 50%.
From the above, it can be seen that, in the recovery method provided by the embodiment, the yield of DMC is more than 92%, while in the recovery method provided by the comparative example, the yield of DMC is lower than 50%, that is, the recovery method of waste silicone rubber provided by the invention can better recover DMC in waste silicone rubber by combining two cracking reactions, thereby fully utilizing resources in waste silicone rubber.
The above is only a preferred embodiment of the present invention, and it is not intended to limit the scope of the invention, and various modifications and changes will occur to those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention shall be included in the scope of the present invention.
Claims (9)
1. The method for recycling the waste silicone rubber is characterized by comprising the following steps:
s10, crushing and sieving the pretreated waste silicone rubber to obtain waste silicone rubber powder;
s20, mixing the waste silicon rubber powder with alkali metal hydroxide, and reacting under the conditions of water vapor at 120-160 ℃, inert atmosphere and high pressure of 3-5 MPa to primarily crack the waste silicon rubber powder to obtain a crude product DMC;
s30, stirring the crude product DMC and the dilute sulfuric acid solution at 140-150 ℃ to enable the crude product DMC to undergo further depolymerization and rearrangement reaction to obtain an intermediate;
s40, rectifying the intermediate to obtain the refined DMC.
2. The method for recycling waste silicone rubber according to claim 1, wherein in step S10, the pretreatment step includes:
and cleaning and drying the waste silicon rubber.
3. The method for recycling waste silicone rubber according to claim 1, wherein step S10 includes:
carrying out primary crushing treatment on the pretreated waste silicon rubber to obtain waste silicon rubber particles;
and finely crushing the waste silicon rubber particles, and sieving the crushed waste silicon rubber particles with a 50-100-mesh sieve to obtain waste silicon rubber powder.
4. The method for recycling waste silicone rubber according to claim 1, wherein in step S20, the mass ratio of the alkali metal hydroxide to the waste silicone rubber powder is (0.2 to 2): 100.
5. the method for recycling waste silicone rubber according to claim 1, wherein in step S20, the alkali metal hydroxide is sodium hydroxide or potassium hydroxide.
6. The method for recycling waste silicone rubber according to claim 1, wherein in step S30:
in the dilute sulfuric acid solution, the mass fraction of the sulfuric acid is 50-65%.
7. The method for recycling waste silicone rubber according to claim 1, wherein in step S30:
the mass ratio of the crude DMC to the dilute sulfuric acid is 10: (0.1-0.5).
8. The method for recycling waste silicone rubber according to claim 1, wherein in step S30:
the stirring time is 120-180 min.
9. The method for recycling waste silicone rubber according to claim 1, wherein in step S40:
the temperature of the rectification treatment is 150-250 ℃.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110776667.0A CN113563376B (en) | 2021-07-08 | 2021-07-08 | Recovery method of waste silicone rubber |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110776667.0A CN113563376B (en) | 2021-07-08 | 2021-07-08 | Recovery method of waste silicone rubber |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113563376A true CN113563376A (en) | 2021-10-29 |
| CN113563376B CN113563376B (en) | 2023-11-07 |
Family
ID=78164247
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110776667.0A Active CN113563376B (en) | 2021-07-08 | 2021-07-08 | Recovery method of waste silicone rubber |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113563376B (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114031636A (en) * | 2021-11-12 | 2022-02-11 | 福建师范大学 | Mechanical force chemical grinding assisted waste silicon rubber thermal cracking recovery method |
| CN114516977A (en) * | 2022-03-07 | 2022-05-20 | 广东省科学院资源利用与稀土开发研究所 | Method for recovering cyclosiloxane monomer by cracking waste silicone rubber under catalysis of rare earth |
| CN115156239A (en) * | 2022-07-15 | 2022-10-11 | 山东邦凯新材料有限公司 | Device and processing technology for preparing high-purity silicon dioxide by continuous recovery treatment of hazardous waste silica gel |
| CN115368400A (en) * | 2022-09-20 | 2022-11-22 | 湖北鑫金鹏新材料有限公司 | Process for recovering organic silicon ring body from silicon rubber series substances |
| CN116284990A (en) * | 2023-03-30 | 2023-06-23 | 江门市江业豪硅材料有限公司 | Method and device for recycling silicone rubber |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SU939445A1 (en) * | 1980-12-12 | 1982-06-30 | Предприятие П/Я Г-4236 | Process for producing organocyclosiloxanes |
| CN102134331A (en) * | 2011-01-21 | 2011-07-27 | 合肥工业大学 | Recycling method of waste silicone rubber |
| CN103626797A (en) * | 2012-08-28 | 2014-03-12 | 杨晓林 | Steam cracking recovery method of silicone rubber |
-
2021
- 2021-07-08 CN CN202110776667.0A patent/CN113563376B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SU939445A1 (en) * | 1980-12-12 | 1982-06-30 | Предприятие П/Я Г-4236 | Process for producing organocyclosiloxanes |
| CN102134331A (en) * | 2011-01-21 | 2011-07-27 | 合肥工业大学 | Recycling method of waste silicone rubber |
| CN103626797A (en) * | 2012-08-28 | 2014-03-12 | 杨晓林 | Steam cracking recovery method of silicone rubber |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114031636A (en) * | 2021-11-12 | 2022-02-11 | 福建师范大学 | Mechanical force chemical grinding assisted waste silicon rubber thermal cracking recovery method |
| CN114516977A (en) * | 2022-03-07 | 2022-05-20 | 广东省科学院资源利用与稀土开发研究所 | Method for recovering cyclosiloxane monomer by cracking waste silicone rubber under catalysis of rare earth |
| CN114516977B (en) * | 2022-03-07 | 2023-11-24 | 广东省科学院资源利用与稀土开发研究所 | Method for recycling cyclosiloxane monomer by cracking waste silicone rubber under catalysis of rare earth |
| CN115156239A (en) * | 2022-07-15 | 2022-10-11 | 山东邦凯新材料有限公司 | Device and processing technology for preparing high-purity silicon dioxide by continuous recovery treatment of hazardous waste silica gel |
| CN115368400A (en) * | 2022-09-20 | 2022-11-22 | 湖北鑫金鹏新材料有限公司 | Process for recovering organic silicon ring body from silicon rubber series substances |
| CN116284990A (en) * | 2023-03-30 | 2023-06-23 | 江门市江业豪硅材料有限公司 | Method and device for recycling silicone rubber |
| CN116284990B (en) * | 2023-03-30 | 2023-09-19 | 江门市江业豪硅材料有限公司 | Method and device for recycling silicone rubber |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113563376B (en) | 2023-11-07 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN113563376A (en) | Method for recovering waste silicon rubber | |
| CN102134331B (en) | Recycling method of waste silicone rubber | |
| EP2671867A1 (en) | Reclaiming toluenediamine from tar waste residue discharged from synthesis of toluene diisocynate | |
| CN112851502B (en) | Method for catalyzing waste PET polyester to carry out methanol alcoholysis by using choline and terephthalic acid non-metallic ionic liquid | |
| CN112142107A (en) | Method for preparing high-purity vanadium oxychloride from vanadium-containing refined tailings | |
| CN110156030A (en) | A kind of fluorine-containing silicon slag purifying technique of fluosilicic acid | |
| CN111040243B (en) | High-efficiency cracking recovery method of silicon rubber waste | |
| US5277796A (en) | Pretreating oil shale with organic acid to increase retorting yield and process efficiency | |
| US4137266A (en) | Process for toluene diamine recovery | |
| CN107311929B (en) | Preparation method of caprolactam | |
| EP2738152B1 (en) | Method for removal and recovery of organic amines from a hydrocarbon stream | |
| CN101092319A (en) | Method for separating cyclopentadiene | |
| CN101767860A (en) | Recovery process of caprolactam refining raffinate | |
| US20020156334A1 (en) | Process for producing purified dicyclopentadiene and 5-ethylidene-2-norbornene | |
| KR20090089246A (en) | Method for seperating and recovering polyol from decomposing polyurethane and process for producing polyurethane foam using the same | |
| CN114085381B (en) | Gas phase dimethyl dichlorosilane hydrolysis process | |
| US2827423A (en) | Preparation of acrylonitrile | |
| WO2014007295A1 (en) | Method for decomposing plant biomass, and method for producing glucose | |
| CA1294625C (en) | Process for producing coarse-crystalline high-purity nicotinic acid | |
| CN107628927B (en) | Method for synthesizing alpha-terpineol from limonene | |
| CN108129509A (en) | It is a kind of to recycle the method for waste generated in protected silane reaction process | |
| JP6450503B1 (en) | Method for producing tar acid | |
| CN108997124B (en) | Method for recovering nitrobenzene from nitrobenzene tar | |
| CN105271306A (en) | Method for purifying cyan chloride crude product | |
| US7416645B2 (en) | Continuous process for recovering acetone from a waste stream resulting from acetone purification |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |