CN106587114A - Method for preparing sodium sulfite solution by using polysulfide rubber polymerized mother liquor acidized gas - Google Patents
Method for preparing sodium sulfite solution by using polysulfide rubber polymerized mother liquor acidized gas Download PDFInfo
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- CN106587114A CN106587114A CN201611118004.5A CN201611118004A CN106587114A CN 106587114 A CN106587114 A CN 106587114A CN 201611118004 A CN201611118004 A CN 201611118004A CN 106587114 A CN106587114 A CN 106587114A
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- sodium sulfite
- thiorubber
- sulfur dioxide
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- mother liquid
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01D—COMPOUNDS OF ALKALI METALS, i.e. LITHIUM, SODIUM, POTASSIUM, RUBIDIUM, CAESIUM, OR FRANCIUM
- C01D5/00—Sulfates or sulfites of sodium, potassium or alkali metals in general
- C01D5/14—Preparation of sulfites
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Abstract
The invention relates to a method for preparing a sodium sulfite solution by using a polysulfide rubber polymerized mother liquor acidized gas. Preparation raw materials according the method include the polysulfide rubber polymerized mother liquor acidized gas; the polysulfide rubber polymerized mother liquor acidized gas comprises sulfur dioxide and hydrogen sulfide; equipment comprises a hydrogen sulfide absorption device, a sulfur dioxide absorption tower and a water ejection pump. The method is characterized by comprising the following steps: A, absorbing hydrogen sulfide, namely, introducing the polysulfide rubber polymerized mother liquor acidized gas into the hydrogen sulfide absorption device so as to obtain a sulfur dioxide purified gas; B, preparing a sodium sulfite solution, namely, introducing the sulfur dioxide purified gas into the sulfur dioxide absorption tower, and performing two-stage absorption by using an absorption liquid, namely a sodium hydroxide solution, in the sulfur dioxide absorption tower and the water ejection pump, thereby obtaining a finished solution of sodium sulfite. By adopting the method, the polysulfide rubber polymerized mother liquor acidized gas can be effectively recycled and utilized, environmental pollution can be reduced, sufficient utilization of resources can be achieved, and the production cost can be lowered.
Description
Technical field
The present invention relates to thiorubber. polymeric mother liquid acidifying Gas recovery, and in particular to a kind of poly- using thiorubber.
The method that mother liquor acid activating QI body prepares sodium sulfite solution is closed, belongs to thiorubber. production technical field.
Background technology
Polysulfide sealant (thiorubber .) has special oil resistant, solvent resistant, ageing-resistant characteristic, and air-tightness, watertight
Property, cryogenic subduing flexibility, electric insulating quality are excellent, and these excellent specific properties of polysulfide sealant make it in Aeronautics and Astronautics, building, vapour
All it is used widely in the fields such as car, ship, machinery, petrochemical industry and electric meter.
Polysulfide sealant is obtained by the polyreaction of Dichloroethyl formal and aqueous sodium polysulfide.First,
The two carries out polycondensation reaction, generates the polysulfide rubber latex of water-fast high molecular, the Sodium Chloride of by-product, excessive sodium polysulphide
And the sodium thiosulfate brought into aqueous sodium polysulfide etc. is all soluble in water, after Jing washings, cracking, cohesion, be dried etc.
Operation prepares liquid polysulfide rubber.The washing step of thiorubber. unavoidably produces sulfur-containing waste water, the waste water chemistry consumption
Oxygen amount (COD) higher (close 10000mg/L), and salinity is larger, it is difficult to process.Such as：Yang Qinglin exists《Liaoning chemical industry》1992
(4) in " improvement of thiorubber. sour water " text, air oxidation process, biological oxidation process, oxychloride method, hypochlorous acid are described
The processing methods such as sodium oxidizing process.But said method there are problems that various, have plenty of engineering issues, have plenty of cost and ask
Topic, has plenty of secondary pollution problem, and said method is not practical.Han Xian equalitys exist《Applicating technology》2009 (15) " sulfur glue give up
In the design and operation of a water process " text, the method that two-step method processes thiorubber. technique waste water is described, first by Waste
The sulfide removal being harmful in water carries out mixing and reduces pollution factor into nontoxic or low toxicity material, then waste water and waste water lower clearly
After concentration, biochemical treatment is carried out.As can be seen here thiorubber. technique waste water can not directly biochemical treatment, can not pass through single
Either physically or chemically process up to standard.
Increase a polymeric mother liquid separation circuit before thiorubber. washing step, thiorubber. polymeric mother liquid is extracted
Individually to carry out pretreatment, then can greatly reduce thiorubber. washing waste water discharge capacity, and reduce processing cost.Polymeric mother liquid is dirty
The dye factor is very high, and main component is：Sodium polysulphide (in terms of sodium sulfide) 10～15g/L, 50～60g/L of sodium thiosulfate, chlorination
25000～35000mg/L of 30～35g/L of sodium, CODcr.Polymeric mother liquid Jing sulphuric acid or hydrochloric acid acidification, can effectively remove height
The sodium polysulphide and sodium thiosulfate of toxicity, greatly reduces the COD of waste water.The gas that polymeric mother liquid acidification is produced is dioxy
Change sulfur and sulfuration hydrogen mixed gas (hydrogen sulfide content 7.5%～10.0%), it is necessary to recycled.
It is general process route to prepare sodium sulfite with sulfur dioxide gas, has soda absorption process and sodium hydroxide to absorb
Method.There are sulfur burning and metallurgy industry flue gas etc. in the source of sulfur dioxide, but there are no with thiorubber. mother liquor acid activating QI body
(being mixed with the sulfur dioxide gas of hydrogen sulfide) is the report of raw material.Such as (Flos Bombacis Malabarici steel enterprise is glad for the application for a patent for invention of Tang Runbing
Space Chemical Co., Ltd., application number 201510875445.9) propose it is anti-with sulfur dioxide by absorbing liquid of sodium hydroxide solution
Should, the method for obtaining sodium sulfite solution.(Tianjin Changlu Hangu Salt Field's Limited Liability is public for the application for a patent for invention of Zhou Qingyun etc.
Department, application number 201510881881.7) propose the process route that sodium sulfite is prepared with soda ash solution sulfur dioxide absorption.
Set up, Zhang Qingguo exists《Bohai University's journal》(natural science edition) the 1st phase " SO of volume 322Flue gas Alkali absorption continuous prodution is sub-
In the text of the technical study of sodium sulfate ", it was recently reported that the sulfur dioxide flue gas Jing Alkali absorptions produced using calcining molybdenum ore concentrate prepare sub-
The technique of sodium sulfate.
The content of the invention
Present invention aim to address thiorubber. polymeric mother liquid acidifying gas is unable to the problem of effective recycling, can be with
Environmental pollution and energy twice laid are reduced, production cost is reduced.
For achieving the above object, the present invention provides one kind and prepares sodium sulfite using thiorubber. polymeric mother liquid acidifying gas
The method of solution, its preparing raw material includes that thiorubber. polymeric mother liquid is acidified gas, and the thiorubber. polymeric mother liquid is acidified gas
Body includes sulfur dioxide, hydrogen sulfide, and equipment includes hydrogen sulfide absorption device, sulfur dioxide absorbing tower, water stream injection pump, and its feature exists
In comprising the steps of：
A. hydrogen sulfide is absorbed：Thiorubber. polymeric mother liquid acidifying gas is passed through into hydrogen sulfide absorption device, two are obtained
Sulfur oxide purification gas；
B. sodium sulfite solution is prepared：Purging sulfur dioxide gas is passed through into sulfur dioxide absorbing tower, absorbing liquid is hydrogen-oxygen
Change sodium solution, absorb through sulfur dioxide absorbing tower and water stream injection pump two-stage, obtain sodium sulfite final mean annual increment solution.
Specifically, in the thiorubber. polymeric mother liquid acidifying gas, content of sulfur dioxide 85%～90%, hydrogen sulfide
Content is 7.5%～10.0%.
Specifically, while thiorubber. polymeric mother liquid acidifying gas is passed through into hydrogen sulfide absorption device, control
Inlet air intake makes system vacuum maintain 0.045～0.05MPa.
Specifically, the sodium hydroxide solution is that ionic membrane sodium hydroxide and water are formulated, and concentration is 100～120g/L
(2.5～3.0mol/L).
Specifically, hydrogen sulfide absorption device selects fiberglass packed tower, and wherein filler is to be situated between in DN50 ceramic raschig rings, tower
Matter is containing Fe3+Aqueous solution；Sulfur dioxide absorbing tower selects 15m2Graphite RPP falling-film absorber；Water stream injection pump is selected
RPP water-jet pump unit.
Specifically, in step B, when sulfur dioxide absorbing tower absorbing liquid pH value is down to 8～9, stop absorbing, obtain sulfurous
Sour sodium final mean annual increment solution, and sodium sulfite final mean annual increment solution is sent in sodium sulfite finished pot.
The application has an advantageous effect in that compared with prior art：
Using the present invention, can effective recycling thiorubber. polymeric mother liquid acidifying gas, reduce environmental pollution.Also,
Gained sodium sulfite solution purity is high, without sodium sulfide.In view of cracking in operation in thiorubber. production needs sodium sulfite molten
Liquid as decomposition agent, therefore, by gained sodium sulfite be back to thiorubber. production, you can realize making full use of for resource, and
Production cost can be reduced.
Description of the drawings
Below in conjunction with the accompanying drawings the present invention is described further.
Fig. 1 is the process chart of the present invention.
Specific embodiment
For a further understanding of the present invention, the preferred embodiment of the invention is described with reference to embodiment.
Referring to Fig. 1, unstripped gas therein is acidifying gas, i.e. thiorubber. polymeric mother liquid acidifying gas, two in unstripped gas
Sulfur oxide content 85%～90%, the content of hydrogen sulfide is 7.5%～10.0%.Alkali liquor is sodium hydroxide solution, is ionic membrane
Sodium hydroxide and water are formulated, and concentration is 100～120g/L (2.5～3.0mol/L), for sulfur dioxide absorption.Hydrogen sulfide
Absorption plant selects Φ 400 × 4000 (diameter 400mm, height 4000mm) fiberglass packed tower, and wherein filler is that DN50 is ceramic
Raschig ring.Sulfur dioxide absorbing tower selects 15m2 graphite RPP falling-film absorbers.Water stream injection pump selects RPP
Water-jet pump unit, maximum rate of air sucked in required 80m3/h, power of motor 7.5kW.
Before manufacture, polymeric mother liquid acidified waste water 370L and 3kg Iron trichloride hexahydrate is added in fiberglass packed tower, is contained
Fe3+Aqueous medium.And open the sodium hydroxide solution circulating pump of sulfur dioxide absorbing tower.
First thiorubber. polymeric mother liquid acidifying gas is passed through into fiberglass packed tower, meanwhile, by control device import
Air intake makes system vacuum maintain 0.045～0.05MPa, makes whole technical process carry out improving peace under negative pressure
Quan Xing.There is the acidified waste water containing ferric chloride, in Fe in packed tower3+In the presence of, hydrogen sulfide and sulfur dioxide reaction generate
Sulfur precipitation enters sulfur filtration equipment, and sulfur dioxide excess, so as to hydrogen sulfide in mixed gas be eliminated, obtains sulfur dioxide
Purification gas.
Purging sulfur dioxide gas is passed through into sulfur dioxide absorbing tower, is absorbed through absorption tower and water stream injection pump two-stage, when
When sulfur dioxide absorbing tower absorbing liquid pH value is down to 8～9, stop absorbing, obtain sodium sulfite final mean annual increment solution, and by sodium sulfite
Final mean annual increment solution is sent in sodium sulfite finished pot.
Preferably to embody the technology of the present invention effect, one group of comparative example is also done, compared with embodiment, comparative example removes work
Hydrogen sulfide absorption device in skill flow process.Thiorubber. polymeric mother liquid acidifying gas is passed directly into into sulfur dioxide absorbing tower and water
Jet pump system is absorbed.
Table 1
| Numbering | Embodiment 1 | Embodiment 2 | Embodiment 3 | Comparative example |
| Unstripped gas hydrogen sulfide content, % | 8.6 | 8.8 | 8.2 | 8.4 |
| Unstripped gas content of sulfur dioxide, % | 88.3 | 87.9 | 86.7 | 87.5 |
| Concentration of sodium hydroxide solution, g/L | 106 | 112 | 115 | 114 |
| Soak time, h | 6.0 | 6.2 | 6.0 | 4.5 |
| Endpoint pH | 8.5 | 8.6 | 9.0 | 8.6 |
| Sodium sulfite solution concentration, g/L | 168 | 171 | 175 | 158 |
| Sodium sulfide content, g/L | 0 | 0 | 0 | 16 |
Note：Unstripped gas composition is meansigma methodss in course of reaction.
Table 1 is that three groups of embodiments are contrasted with the experimental data of comparative example, it can be seen that the gained sodium sulfite of embodiment 1～3
Solution purity is high, without sodium sulfide.In view of cracking in operation in thiorubber. production sodium sulfite solution is needed as decomposition agent,
Therefore, gained sodium sulfite is back to into thiorubber. production, you can realize making full use of for resource, can reduce producing into again
This.And the gained sodium sulfite solution of comparative example 1 contains more sodium sulfide composition, it is difficult to recycle.
Above-described embodiment is only intended to clearly illustrate example of the present invention, and is not to embodiments of the present invention
Restriction.For those of ordinary skill in the field, other not similar shapes can also be made on the basis of the above description
The change or change of formula.All any modification, equivalent substitution and improvements within the spirit and principles in the present invention, done etc. are wrapped
Among being contained in protection scope of the present invention.
Claims (7)
1. a kind of method that utilization thiorubber. polymeric mother liquid acidifying gas prepares sodium sulfite solution, its preparing raw material includes poly-
Sulphur rubber polymeric mother liquid is acidified gas, and the thiorubber. polymeric mother liquid acidifying gas includes sulfur dioxide, hydrogen sulfide, equipment bag
Include hydrogen sulfide absorption device, sulfur dioxide absorbing tower, water stream injection pump, it is characterised in that comprise the steps of：
A. hydrogen sulfide is absorbed：Thiorubber. polymeric mother liquid acidifying gas is passed through into hydrogen sulfide absorption device, titanium dioxide is obtained
Sulfur purification gas；
B. sodium sulfite solution is prepared：Purging sulfur dioxide gas is passed through into sulfur dioxide absorbing tower, absorbing liquid is sodium hydroxide
Solution, absorbs through sulfur dioxide absorbing tower and water stream injection pump two-stage, obtains sodium sulfite final mean annual increment solution.
2. the method that utilization thiorubber. polymeric mother liquid acidifying gas according to claim 1 prepares sodium sulfite solution,
It is characterized in that：In the thiorubber. polymeric mother liquid acidifying gas, content of sulfur dioxide 85%～90%, the content of hydrogen sulfide
For 7.5%～10.0%.
3. utilization thiorubber. polymeric mother liquid acidifying gas according to claim 1 and 2 prepares the side of sodium sulfite solution
Method, it is characterised in that：While thiorubber. polymeric mother liquid acidifying gas is passed through into the hydrogen sulfide absorption device, control
Inlet air intake processed makes system vacuum maintain 0.045～0.05MPa.
4. utilization thiorubber. polymeric mother liquid acidifying gas according to claim 1 and 2 prepares the side of sodium sulfite solution
Method, it is characterised in that：The sodium hydroxide solution is that ionic membrane sodium hydroxide and water are formulated, and concentration is 100～120g/L.
5. utilization thiorubber. polymeric mother liquid acidifying gas according to claim 1 and 2 prepares the side of sodium sulfite solution
Method, it is characterised in that：The hydrogen sulfide absorption device select fiberglass packed tower, wherein filler be DN50 ceramic raschig rings, tower
Interior medium is containing Fe3+Aqueous solution；The sulfur dioxide absorbing tower selects 15m2Graphite RPP falling-film absorber；It is described
Water stream injection pump selects RPP water-jet pump unit.
6. utilization thiorubber. polymeric mother liquid acidifying gas according to claim 1 and 2 prepares the side of sodium sulfite solution
Method, it is characterised in that：In step B, when sulfur dioxide absorbing tower absorbing liquid pH value is down to 8～9, stop absorbing, obtain sulfurous
Sour sodium final mean annual increment solution, and sodium sulfite final mean annual increment solution is sent in sodium sulfite finished pot.
7. the method that utilization thiorubber. polymeric mother liquid acidifying gas according to claim 1 prepares sodium sulfite solution,
It is characterized in that：The sodium sulfite solution of gained is back to into the cracking operation in thiorubber. production.
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| CN201611118004.5A CN106587114B (en) | 2016-12-07 | 2016-12-07 | The method for preparing sodium sulfite solution using polysulfide rubber polymeric mother liquid acidifying gas |
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| CN201611118004.5A CN106587114B (en) | 2016-12-07 | 2016-12-07 | The method for preparing sodium sulfite solution using polysulfide rubber polymeric mother liquid acidifying gas |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN109437119A (en) * | 2018-12-19 | 2019-03-08 | 锦西化工研究院有限公司 | The method that polysulfide rubber sodium polysulfide devil liquor recovery utilizes |
| CN110255585A (en) * | 2019-07-10 | 2019-09-20 | 南京工业大学 | A kind of device and method preparing sulphite |
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| CN103406007A (en) * | 2013-05-16 | 2013-11-27 | 福建省双旗山矿业有限责任公司 | Recovery process for sulphur in gold concentrate roasting smoke |
| CN104289092A (en) * | 2014-09-24 | 2015-01-21 | 重庆市聚益橡胶制品有限公司 | Reclaimed rubber desulfurized tail gas purification device |
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| CN1214274A (en) * | 1998-09-05 | 1999-04-21 | 黄乙林 | Waste gas treating method for viscose fiber production |
| CN1416941A (en) * | 2002-12-12 | 2003-05-14 | 江西省国燕橡胶有限公司 | Technological tail gas purifying method for reclaimed rubber production |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN109437119A (en) * | 2018-12-19 | 2019-03-08 | 锦西化工研究院有限公司 | The method that polysulfide rubber sodium polysulfide devil liquor recovery utilizes |
| CN110255585A (en) * | 2019-07-10 | 2019-09-20 | 南京工业大学 | A kind of device and method preparing sulphite |
| CN110255585B (en) * | 2019-07-10 | 2020-08-18 | 南京工业大学 | Device and method for preparing sulfite |
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| CN106587114B (en) | 2018-03-16 |
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