CN1186250C

CN1186250C - Method for producing stable chlorine dioxide with high purity by using gas stripping technique

Info

Publication number: CN1186250C
Application number: CNB021392382A
Authority: CN
Inventors: 覃庆林
Original assignee: Individual
Current assignee: Individual
Priority date: 2002-10-31
Filing date: 2002-10-31
Publication date: 2005-01-26
Anticipated expiration: 2022-10-31
Also published as: CN1415534A

Abstract

The present invention discloses a method for producing high-purity stable chlorine dioxide by a gas striping method. Firstly, refrigerated water is used for absorbing chlorine dioxide gas to prepare the aqueous solution of chlorine dioxide; then, the chlorine dioxide is stripped from the aqueous solution and reacts with sodium dioxide or sodium percarbonate solution to obtain stable chlorine dioxide. The gas stripping operation of the aqueous solution of chlorine dioxide adopts a negative pressure jet method, namely that air is added into the aqueous solution by negative pressure. The stable ClO2 produced by the method has the maximal superiority that the product is free from the interference of entrainment matter of mother liquor, the quality is stable, and the purity is high; the chlorine dioxide produced by any preparation method can be used for producing high-purity stable ClO2 by the method. The present invention can be widely used in various fields.

Description

Stripping gas formulation high purity stable chlorine dioxide disinfectant production method

Technical field:

The present invention relates to a kind of purifying, separation method of oxide compound, especially a kind of stripping gas formulation high purity stable chlorine dioxide disinfectant production method.

Background technology:

Stable chlorine dioxide disinfectant is a kind of purposes sterilizing agent more widely, domestic and international production technology is comparative maturity all, and common production method is to utilize sodium peroxide or SPC-D solution directly to absorb the chlorine dioxide that is produced by chlorine dioxide generator to make.The disadvantage of this production method is no matter to adopt which kind of chlorine dioxide generation that chlorine dioxide takes place, mother liquor in the producer is easily carried secretly to stable chlorine dioxide disinfectant solution by chlorine dioxide and water vapor, unstable product quality is even adopt with H ₂O ₂For chlorine dioxide takes place for the R11 method of reductive agent, materials such as the sodium chlorate in the mother liquor also can be carried secretly to product, are difficult to obtain highly purified stable state CLO ₂Especially with methyl alcohol the R8 method chlorine dioxide production technology of reductive agent, easier being brought to by the dioxide peroxide that produces from producer and water vapor mixture of lower boiling methyl alcohol makes its quality be affected the stable chlorine dioxide disinfectant product, cause methanol content to exceed standard when serious and make its range of application, field have limitation.

Summary of the invention:

The purpose of this invention is to provide a kind of can be any the dioxide peroxide that produces of dioxide peroxide preparation method produce and obtain high purity stable state CLO ₂Production method, the stable chlorine dioxide disinfectant product of Sheng Chaning is not disturbed by the mother liquor entrainment in this way, purity height, steady quality.

Technological core of the present invention is to adopt earlier before the dioxide peroxide mixed gas that producer comes out contacts with absorption liquid refrigerated water to absorb and forms the aqueous solution of chlorine dioxide that contains from the various compositions the reaction mother liquor, use the negative pressure air blast then, promptly air is blown into CLO under the effect of vacuum ₂In the aqueous solution, because the poor stability of dioxide peroxide and water molecules, dioxide peroxide in the aqueous solution is easy to be discharged by desorb, thereby various compositions such as all the other methyl alcohol from reaction mother liquor, sodium chlorate, sulfuric acid, formic acid are then stayed the purpose that reaches separating impurity in the aqueous solution.The high-purity C LO that from the aqueous solution, desorbs ₂Enter an absorption agent from the bottom and from top spray absorption tower down, carry out the countercurrent washing absorption, even being the R8 method of reductive agent with methyl alcohol, employing produces stable chlorine dioxide disinfectant, boiling point is low, poisonous, the big methyl alcohol of quality product influence also can be removed up hill and dale, means promptly that also method of the present invention is applicable to adopting R8 method production of high purity in next life stable chlorine dioxide disinfectant.In numerous chlorine dioxide generations, therefore the advantage that R8 method chlorine dioxide generation has the transformation efficiency height, be easy to control, the byproduct cl content is low and production cost is low has very important realistic meaning.

At first use refrigerated water to absorb the chlorine dioxide that contains various compositions that comes out from producer and make aqueous solution of chlorine dioxide, then dioxide peroxide stripping gas from the aqueous solution is put forward the stable chlorine dioxide disinfectant that exists with chlorite's form with sodium peroxide or the acquisition of SPC-D solution reaction.The stripping gas of aqueous solution of chlorine dioxide is carried and is adopted the negative pressure air blast, and promptly air is that effect by negative pressure is added in the aqueous solution.The temperature of refrigerated water is 6～8 ℃.

The stable state CLO of Sheng Chaning in this way ₂Sharpest edges are interference that product is not subjected to the mother liquor entrainment, steady quality, purity height, in this way can be any the dioxide peroxide that produces of dioxide peroxide preparation method produce and obtain high purity stable state CLO ₂Can widespread use in every field.

Description of drawings:

Fig. 1 is a Production Flow Chart synoptic diagram of the present invention.

Embodiment:

Technical process of the present invention is:

In chlorine dioxide generator 3, sodium chlorate is reduced agent (as R under strongly-acid ₈The reductive agent of method is a methyl alcohol) reduction generation chlorine dioxide, the mother liquor in the producer is circulating in the circulation loop in negative pressure state under the effect of recycle pump 1, and obtains heating through reboiler 2 time.The effect of the Explosion-proof cap 4 on the producer top is to decompose when producer internal cause dioxide peroxide, is backed down when pressure raises suddenly, plays the effect of protection producer and loop thereof.The mixed gas that contains chlorine dioxide, water vapor and entrainment mother liquor that comes out from producer 3 enters indirect cooler 5, most of water vapor in the mixed gas is condensed, cooled chlorine dioxide enters absorption tower 6 from the bottom, the refrigerated water that is got off from the absorption tower top spray absorbs the about 14 ℃ aqueous solution of chlorine dioxide of temperature that obtains to contain various impurity, and is delivered in the storagetank 8 that has thermal insulation layer by pump 7.Aqueous solution of chlorine dioxide is delivered to by pump 9 and separates in the cucurbitula 10, absorption tower 12 vacuum action make that separating cucurbitula is in negative pressure state, therefore air is blown into the aqueous solution of chlorine dioxide from the desorb pot bottom by air filter 11 backs under the effect of negative pressure, the bubbling vibration of air in the aqueous solution makes discharge original the separation with the dioxide peroxide of water molecules poor stability, on the other hand, the air that is blown into the aqueous solution has quickened the isolating speed of dioxide peroxide and water molecules again after rapidly the temperature of the aqueous solution being improved.By the effect that stripping gas is carried, have only dioxide peroxide to be separated, all the other are then stayed the aqueous solution from the various impurity that mother liquor brings.The absorption liquid contact reacts of the chlorine dioxide that is desorbed under air enters stable chlorine dioxide disinfectant absorption tower 12 and sprays from the top from the bottom obtains highly purified stable chlorine dioxide disinfectant solution, is delivered in the storagetank 14 through pump 13 and stores.

The innovation part of the inventive method is to utilize the character of dioxide peroxide and water combination stability difference.Solubleness and the water temperature of dioxide peroxide in water is inversely proportional to, and temperature low solubility more is big more, otherwise high-dissolvability is more little more for temperature, in order to improve CLO ₂Solubleness in water, earlier the chlorine dioxide that is entrained with compositions such as sodium chlorate, sulfuric acid, methyl alcohol and formic acid that discharges from chlorine dioxide generator with about 7 ℃ refrigerated water absorption and obtaining contains the aqueous solution of chlorine dioxide of the about 10g/l of concentration of these entrainments.Because dioxide peroxide and water molecules power are low, therefore, as past CLO ₂When the aqueous solution was blown into air, air discharged in the bubbling vibration of the aqueous solution feasible the separation with the unsettled dioxide peroxide of water molecules power, and after being blown into rapid raising of temperature of air with the aqueous solution of the aqueous solution, CLO ₂Solubleness in water reduces greatly, has aggravated CLO again ₂With separating of water molecules, the CLO that from the aqueous solution, overflows ₂Fully diluted after the air mixed that gas is added continually, guaranteed CLO ₂The branch of gas is pressed in below the safe dividing potential drop.In order to improve CLO ₂The security of mixed gas reduces CLO ₂Decomposition, the absorption tower is produced 16 kPas vacuum by the suction of vacuum ejector.CLO ₂Generate stable chlorine dioxide disinfectant with absorption liquid (sodium peroxide or SPC-D solution) the counter current contact reaction that sprays into from the top after entering the absorption tower by the vacuum take-off effect from the bottom on absorption tower with Air mixing gas.At the initial period of bubbling air, because chlorine dioxide concentration height in the aqueous solution, the speed that dioxide peroxide discharges from water is very fast, CLO in the solution after the about five minutes kinds ₂Concentration is lowered to about 2g/l.Along with CLO ₂The reduction of concentration of aqueous solution, CLO ₂The speed of desorb can become slowly from water, works as CLO ₂When concentration reduced, the yellow-green colour color of the aqueous solution can shoal gradually, according to CLO ₂The color of the aqueous solution can be judged CLO ₂The desorb degree, in order to enhance productivity, desorption time can be controlled at 30min, CLO in the desorb terminal point aqueous solution ₂Concentration≤0.5g/l.Can be by such process effectively CLO ₂From the aqueous solution, separate and produce highly purified stable chlorine dioxide disinfectant.Owing to contain many dust in the air, therefore an air filter is installed at the air suction inlet place is clean with the air that guarantees to be used for gas and carry.CLO through desorb ₂The aqueous solution can be recycled and reused for CLO ₂The absorption of producer gas also can be discharged after reductive agent is handled through dripping.But owing to contained a certain amount of CLO by the aqueous solution of desorb ₂, be reused for CLO ₂Need before absorbing could use after overcooling, therefore require the material of refrigerating unit to have stronger erosion resistance, make equipment investment cost strengthen, therefore, the kind mode is handled the back discharging after the suggestion.Also because CLO ₂Characteristic, CLO ₂Obtaining the approval of environmental protection industry in the application in waste water control field, not high as emission concentration, discharge and contain a small amount of CLO ₂The aqueous solution helpful on the contrary to place that sewage discharge is arranged, help environment protection.

Embodiment:

In having the dissolving tank of agitator, add 50M ³Clear water starts agitator, with the Na of 1250Kg ₂CO ₃The NaOH that reaches 1190Kg pours in the dissolving tank, after treating all to dissolve, slowly adds the H of 1250Kg ₂O ₂(100%), add the back and continue to stir 30min, the absorption liquid that so prepares is placed after 24 hours and can be used.

Being equipped with dioxide peroxide with the R8 legal system is example, and 164 kilograms sodium chlorate, 100 kilograms of sulfuric acid and 15 kilograms of methyl alcohol react in producer, can produce 100 kilograms chlorine dioxide, obtains the aqueous solution of chlorine dioxide 10t that concentration is every liter 10 gram with 7 ℃ refrigerated waters.The aqueous solution is transferred to separate and carries out stripping gas in the cucurbitula and carry, and the chlorine dioxide precursor reactant that puts forward with absorption liquid for preparing and gas makes the stable chlorine dioxide disinfectant 50t of content about 2% again.

Claims

1, a kind of stripping gas formulation high purity stable chlorine dioxide disinfectant production method, it is characterized in that: at first use refrigerated water to absorb chlorine dioxide and make aqueous solution of chlorine dioxide, adopt the negative pressure air blast then, be that air is blown in the aqueous solution of chlorine dioxide under suction function, dioxide peroxide stripping gas in the aqueous solution is put forward, obtain stable chlorine dioxide disinfectant with sodium peroxide or SPC-D solution reaction again.