CN111717892A - Method for preparing high-purity high-concentration hydrochloric acid by hydrothermal hydrolysis of organic silicon high-boiling residues - Google Patents
Method for preparing high-purity high-concentration hydrochloric acid by hydrothermal hydrolysis of organic silicon high-boiling residues Download PDFInfo
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- CN111717892A CN111717892A CN202010754697.7A CN202010754697A CN111717892A CN 111717892 A CN111717892 A CN 111717892A CN 202010754697 A CN202010754697 A CN 202010754697A CN 111717892 A CN111717892 A CN 111717892A
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- hydrochloric acid
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- purity
- boiling
- gas
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- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 title claims abstract description 124
- 238000000034 method Methods 0.000 title claims abstract description 31
- 238000009835 boiling Methods 0.000 title claims abstract description 25
- 230000007062 hydrolysis Effects 0.000 title claims abstract description 17
- 238000006460 hydrolysis reaction Methods 0.000 title claims abstract description 17
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 title claims abstract description 5
- 229910052710 silicon Inorganic materials 0.000 title claims abstract description 5
- 239000010703 silicon Substances 0.000 title claims abstract description 5
- 239000007788 liquid Substances 0.000 claims abstract description 45
- 239000005046 Chlorosilane Substances 0.000 claims abstract description 20
- KOPOQZFJUQMUML-UHFFFAOYSA-N chlorosilane Chemical compound Cl[SiH3] KOPOQZFJUQMUML-UHFFFAOYSA-N 0.000 claims abstract description 20
- 239000002904 solvent Substances 0.000 claims abstract description 19
- 239000002253 acid Substances 0.000 claims abstract description 18
- 239000002699 waste material Substances 0.000 claims abstract description 15
- 238000000926 separation method Methods 0.000 claims abstract description 14
- 239000011259 mixed solution Substances 0.000 claims abstract description 13
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 12
- 238000010438 heat treatment Methods 0.000 claims abstract description 10
- 238000002156 mixing Methods 0.000 claims abstract description 10
- 238000004064 recycling Methods 0.000 claims abstract description 5
- 239000000243 solution Substances 0.000 claims description 5
- 239000000126 substance Substances 0.000 abstract description 6
- 239000003595 mist Substances 0.000 abstract description 4
- 238000003912 environmental pollution Methods 0.000 abstract description 3
- 238000002360 preparation method Methods 0.000 abstract description 3
- 230000000694 effects Effects 0.000 abstract description 2
- 229910000041 hydrogen chloride Inorganic materials 0.000 description 15
- IXCSERBJSXMMFS-UHFFFAOYSA-N hydrogen chloride Substances Cl.Cl IXCSERBJSXMMFS-UHFFFAOYSA-N 0.000 description 15
- 239000007789 gas Substances 0.000 description 14
- 239000011552 falling film Substances 0.000 description 9
- 239000006096 absorbing agent Substances 0.000 description 8
- 239000002920 hazardous waste Substances 0.000 description 7
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 5
- 229910002804 graphite Inorganic materials 0.000 description 5
- 239000010439 graphite Substances 0.000 description 5
- 238000004519 manufacturing process Methods 0.000 description 5
- 238000010521 absorption reaction Methods 0.000 description 4
- 238000005406 washing Methods 0.000 description 4
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 3
- 239000000460 chlorine Substances 0.000 description 3
- 229910052801 chlorine Inorganic materials 0.000 description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 238000009833 condensation Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 239000012535 impurity Substances 0.000 description 2
- GEHJYWRUCIMESM-UHFFFAOYSA-L sodium sulfite Chemical compound [Na+].[Na+].[O-]S([O-])=O GEHJYWRUCIMESM-UHFFFAOYSA-L 0.000 description 2
- 238000001179 sorption measurement Methods 0.000 description 2
- 238000003860 storage Methods 0.000 description 2
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000002485 combustion reaction Methods 0.000 description 1
- 230000005494 condensation Effects 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 230000003301 hydrolyzing effect Effects 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 238000002386 leaching Methods 0.000 description 1
- 239000012528 membrane Substances 0.000 description 1
- 238000005272 metallurgy Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 230000008092 positive effect Effects 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 235000010265 sodium sulphite Nutrition 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 238000003786 synthesis reaction Methods 0.000 description 1
- 229910021642 ultra pure water Inorganic materials 0.000 description 1
- 238000000108 ultra-filtration Methods 0.000 description 1
- 239000012498 ultrapure water Substances 0.000 description 1
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Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B7/00—Halogens; Halogen acids
- C01B7/01—Chlorine; Hydrogen chloride
Abstract
A method for preparing high-purity high-concentration hydrochloric acid by hydrothermal hydrolysis of organic silicon high-boiling residues comprises the following steps: (1) hydrochloric acid with the concentration of 20-30% is used as a solvent, and chlorosilane high-boiling residues and the solvent are uniformly mixed to form a mixed solution; (2) heating the mixed solution to 35-100 ℃ to hydrolyze the Si-Cl bond along with the temperature rise; (3) heating the mixed solution to 35-100 ℃ to perform gas-liquid separation, and releasing HCl gas; (4) absorbing HCl gas by water to obtain hydrochloric acid with required high concentration; (5) and performing solid-liquid separation on liquid generated after gas-liquid separation, and mixing the waste acid liquid and the hydrochloric acid for recycling. The method has the advantages of simple process, safe and reliable operation, waste treatment by waste, avoidance of hydrochloric acid mist dissipation and environmental pollution caused by hydrolysis of the chlorosilane high-boiling-point substances, reduction of the treatment cost of the chlorosilane high-boiling-point substances, preparation of high-purity high-concentration hydrochloric acid, high treatment efficiency, thorough treatment, good effect and low cost.
Description
Technical Field
The invention relates to a method for preparing hydrochloric acid by using organic silicon high-boiling residues (chlorosilane hazardous waste), in particular to a method for preparing high-purity high-concentration hydrochloric acid, and belongs to the technical field of resource utilization of chlorosilane hazardous waste.
Background
In the prior art, the high-concentration and high-purity hydrochloric acid solution is prepared by a rectification-condensation method, and the final rectification is a main process. If the pure rectification process is adopted, only about 8-10% of dilute acid can be obtained. The recovery of dilute hydrochloric acid is difficult in industry, the acid washing in metallurgy industry is generally to recover dilute acid (simple evaporation concentration), the dilute acid is mixed with concentrated acid to obtain 20% of acid for main process (acid washing or leaching), and if the concentrated acid is obtained by using 5% of dilute acid, the technical difficulty is large and the economical efficiency is poor. The new technologies of salt-adding rectification, membrane separation and the like have higher difficulty and higher cost.
Chinese patent document CN109761196A discloses a method for producing electronic grade hydrochloric acid, comprising the following steps: 1. feeding the synthesized hydrogen chloride gas into an adsorption tower to remove free chlorine; 2. adopting a reagent-grade hydrochloric acid solvent, and entering the washing tower from an inlet at the upper part of the washing tower to wash the adsorbed hydrogen chloride gas so as to remove soluble impurities; 3. the washed hydrogen chloride gas is subjected to primary and secondary condensation and enters a demister, and water mist in the hydrogen chloride gas is removed to obtain high-purity hydrogen chloride gas; 4. absorbing high-purity hydrogen chloride by a primary falling film absorber, a secondary falling film absorber and a tail gas absorption tower, and then obtaining a finished product by a hydrochloric acid cooler; 5. ultrapure water is used as absorption water; 6. and (4) feeding the finished product obtained in the step (4) into a finished product storage tank, and removing particle impurities through ultrafiltration to obtain the electronic grade hydrochloric acid.
CN109678112A discloses a production process of high-purity hydrochloric acid, which comprises the steps of burning chlorine and hydrogen on a combustion table of a synthesis furnace to generate hydrogen chloride gas, and absorbing the hydrogen chloride gas by water in a cooling tower to generate hydrochloric acid with the concentration of 31%; sodium sulfite solution is dripped from the top of the hydrochloric acid storage tank through a dripping tank and fully reacts with free chlorine; the treated hydrochloric acid solution enters a resin tower, and after the tower is filled with the acid solution, redundant iron is removed through adsorption, so that the high-purity hydrochloric acid meeting the production requirement is prepared.
The method is a pure purification process for hydrogen chloride gas production, and cannot bring more beneficial and positive effects in the production process.
Hazardous waste HW49, (309-.
Disclosure of Invention
Aiming at the defects of the existing high-purity high-concentration hydrochloric acid preparation technology, the invention provides the method for preparing the high-purity high-concentration hydrochloric acid by carrying out hydrothermal hydrolysis on the organosilicon high-boiling residues, which realizes the utilization of hazardous wastes, has simple process, low cost and good purity.
The method for preparing high-purity high-concentration hydrochloric acid by hydrothermal hydrolysis of the organosilicon high-boiling components comprises the steps of mixing 20-30% of hydrochloric acid serving as a solvent with chlorosilane high-boiling components, heating to raise the temperature, and hydrolyzing Si-Cl bonds along with the temperature rise to release HCl, wherein the HCl has high purity and can be absorbed by water to obtain high-concentration high-quality industrial hydrochloric acid; the method specifically comprises the following steps:
(1) hydrochloric acid with the concentration of 20-30% is used as a solvent, and chlorosilane high-boiling residues (belonging to hazardous waste HW49) and the solvent are uniformly mixed to form a mixed solution;
the mass ratio of the chlorosilane high-boiling residue to the solvent is 100: 23.6 to 25.1.
The mixed solution is hydrolyzed by water with the mass of 10-12%.
The chlorosilane high-boiling residue and the solvent are mixed by a jet mixer.
(2) Heating the mixed solution to 35-100 ℃ to hydrolyze the Si-Cl bond along with the temperature rise;
the heating temperature is raised at the speed of 20 ℃/hour, the temperature is gradually raised from the mixing temperature to 35-100 ℃, and the constant temperature is kept for 1 hour.
(3) Heating the mixed solution to 35-100 ℃ for gas-liquid separation to release HCl gas;
(4) absorbing HCl gas by water to obtain hydrochloric acid with required high concentration;
(5) and performing solid-liquid separation on liquid generated after gas-liquid separation, and mixing the waste acid liquid and the hydrochloric acid for recycling.
And (2) the waste acid liquid and fresh hydrochloric acid are mixed into hydrochloric acid with the concentration of 20-30% to be used as the solvent in the step (1).
The method has the advantages of simple process, safe and reliable operation, waste treatment by waste, avoidance of hydrochloric acid mist dissipation and environmental pollution caused by hydrolysis of the chlorosilane high-boiling-point substances, reduction of the treatment cost of the chlorosilane high-boiling-point substances, preparation of high-purity high-concentration hydrochloric acid, high treatment efficiency, thorough treatment, good effect and low cost.
Drawings
FIG. 1 is a schematic flow chart of the method for preparing high-purity high-concentration hydrochloric acid by hydrothermal hydrolysis of organosilicon high-boiling components.
Detailed Description
Referring to fig. 1, the apparatus used in the method of the present invention comprises a jet mixer, a heat exchanger, a gas-liquid separator, a solid-liquid separator and a falling film absorber (falling film absorber), wherein the output port of the jet mixer is connected with the inlet of the gas-liquid separator, the gas-liquid separator is connected with the heat exchanger, the upper gas outlet of the gas-liquid separator is connected with the falling film absorber, and the bottom liquid outlet of the gas-liquid separator is connected with the solid-liquid separator. The liquid separated by the gas-liquid separator enters the graphite heat exchanger from the lower part through a pipeline and returns to the gas-liquid separator from the upper end of the heat exchanger after being heated. The heat exchanger is a graphite heat exchanger made of heat transfer component graphite (impervious graphite), and the falling film absorber can also be a graphite falling film absorber. Various devices are known in the art.
Through the above apparatus, the method of the present invention specifically comprises the steps of:
(1) using hydrochloric acid with the concentration of 20-30% as a solvent, respectively conveying 309-49 chlorosilane high-boiling-point substances (belonging to hazardous waste HW49) and the solvent into a jet flow mixer, and mixing and stirring to obtain a mixed solution.
The mass ratio of the chlorosilane high-boiling residue to the solvent is 100: 23.6-25.1, 10% -12% of water by mass participates in hydrolysis, and the specific numerical value is related to process design, for example, more water participates in reaction, and 10% -12% is more reasonable data.
The solvent enters from a nozzle of the jet flow mixer, and the chlorosilane high-boiling-point substance (which is a solid-liquid mixture with slightly high viscosity) enters from an air suction port of the jet flow mixer.
(2) And (3) feeding the mixed liquid output by the jet flow mixer into a gas-liquid separator, feeding the liquid separated by the gas-liquid separator into a heat exchanger for heating, feeding the heated liquid into the gas-liquid separator, and circulating the steps to heat the liquid to 35-100 ℃ so that the Si-Cl bond is hydrolyzed along with the temperature rise.
(3) And (3) carrying out gas-liquid separation on the mixed solution heated to 35-100 ℃ in a gas-liquid separator to release HCl gas with good purity.
(4) The HCl gas generated after gas-liquid separation enters a falling film absorption device (falling film absorber), and high-quality industrial hydrochloric acid with high concentration is obtained through water absorption.
(5) And (2) carrying out solid-liquid separation on liquid generated after the gas-liquid separation in a solid-liquid separator, treating waste residues according to the requirement of carrying out hazardous waste, mixing the waste acid liquid with hydrochloric acid for recycling, and mixing the waste acid liquid with fresh hydrochloric acid to obtain hydrochloric acid with the concentration of 20-30% as a solvent in the step (1).
The method has simple process and low cost, and has the following advantages:
1. the waste is treated by waste, and hydrochloric acid mist dissipation and environmental pollution caused by chlorosilane high-boiling residue hydrolysis are avoided.
2. The whole process is sealed, the environment is purified, and secondary pollution is avoided.
3. Reduces the treatment cost of chlorosilane high-boiling residues and avoids the generation of other pollution sources.
4. High purity and high concentration hydrochloric acid is prepared.
5. The generated waste acid liquid is recycled, and has important significance for processing chlorosilane high-boiling residues and preparing high-purity high-concentration hydrochloric acid.
Claims (6)
1. A method for preparing high-purity high-concentration hydrochloric acid by hydrothermal hydrolysis of organic silicon high-boiling residues is characterized by comprising the following steps:
(1) hydrochloric acid with the concentration of 20-30% is used as a solvent, and chlorosilane high-boiling residues and the solvent are uniformly mixed to form a mixed solution;
(2) heating the mixed solution to 35-100 ℃ to hydrolyze the Si-Cl bond along with the temperature rise;
(3) heating the mixed solution to 35-100 ℃ for gas-liquid separation to release HCl gas;
(4) absorbing HCl gas by water to obtain hydrochloric acid with required high concentration;
(5) and performing solid-liquid separation on liquid generated after gas-liquid separation, and mixing the waste acid liquid and the hydrochloric acid for recycling.
2. The method for preparing high-purity high-concentration hydrochloric acid by hydrothermal hydrolysis of organosilicon high-boiling components as claimed in claim 1, wherein the mass ratio of chlorosilane high-boiling components to solvent in step (1) is 100: 23.6 to 25.1.
3. The method for preparing high-purity high-concentration hydrochloric acid by hydrothermal hydrolysis of organosilicon high-boiling residues as claimed in claim 1, wherein 10-12% by mass of water in the mixed solution of step (1) is involved in hydrolysis.
4. The method for preparing high-purity and high-concentration hydrochloric acid by hydrothermal hydrolysis of organosilicon high-boiling components as claimed in claim 1, characterized in that the mixing of chlorosilane high-boiling components and solvent in step (1) is carried out by means of a jet mixer.
5. The method for preparing high-purity high-concentration hydrochloric acid by hydrothermal hydrolysis of organosilicon high-boiling components as claimed in claim 1, wherein the heating temperature in step (2) is raised at a rate of 20 ℃/hr, gradually raised from the mixing temperature to 35-100 ℃, and kept constant for 1 hour.
6. The method for preparing high-purity high-concentration hydrochloric acid by hydrothermal hydrolysis of organosilicon high-boiling residues as claimed in claim 1, wherein the recycling in step (5) is to mix waste acid solution and fresh hydrochloric acid into hydrochloric acid with a concentration of 20% to 30% as the solvent in step (1).
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| CN202010754697.7A CN111717892A (en) | 2020-07-30 | 2020-07-30 | Method for preparing high-purity high-concentration hydrochloric acid by hydrothermal hydrolysis of organic silicon high-boiling residues |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113213487A (en) * | 2021-04-20 | 2021-08-06 | 云龙县铂翠贵金属科技有限公司 | Comprehensive utilization method of vinyl silane high-boiling residues |
| CN113620247A (en) * | 2021-08-26 | 2021-11-09 | 浙江新安化工集团股份有限公司 | Treatment process of organic silicon high-boiling residues |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101817505A (en) * | 2010-04-30 | 2010-09-01 | 浙江金帆达生化股份有限公司 | Dimethyl dichlorosilane hydrolysis method for directly producing gaseous hydrogen chloride |
| CN105036081A (en) * | 2015-08-03 | 2015-11-11 | 昆明理工大学 | Method for producing HCl gas through chlorosilane residual liquor |
-
2020
- 2020-07-30 CN CN202010754697.7A patent/CN111717892A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101817505A (en) * | 2010-04-30 | 2010-09-01 | 浙江金帆达生化股份有限公司 | Dimethyl dichlorosilane hydrolysis method for directly producing gaseous hydrogen chloride |
| CN105036081A (en) * | 2015-08-03 | 2015-11-11 | 昆明理工大学 | Method for producing HCl gas through chlorosilane residual liquor |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113213487A (en) * | 2021-04-20 | 2021-08-06 | 云龙县铂翠贵金属科技有限公司 | Comprehensive utilization method of vinyl silane high-boiling residues |
| CN113620247A (en) * | 2021-08-26 | 2021-11-09 | 浙江新安化工集团股份有限公司 | Treatment process of organic silicon high-boiling residues |
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Application publication date: 20200929 |