SI8711247A8 - Process for preparing disinfectant concentrate - Google Patents

Description

The invention relates to the field of disinfection or sterilization of a substance and relates to a process for the preparation of a disinfectant concentrate which can be mixed with hydrogen peroxide to form a disinfectant.

A technical problem

Disinfection, in particular the disinfection of water, food and animal feed, as well as equipment, bandages, vessels and all kinds of objects, is a worldwide problem that is equally important in highly civilized nations and in the underdeveloped countries. It is therefore no surprise that intensive research has been carried out in this field for decades and that new products and methods for the non-therapeutic fight against infectious agents are constantly being developed.

- 2 State of the art

Of the many well-known disinfection methods known in the art, the following are examples:

The addition of halogens, such as chlorine, bromine and iodine, or halogen-releasing preparations, is widespread due to the ease of low cost production and the immediate availability of constituent chemicals, as well as the reliable disinfectant effect. The disadvantages are the initial taste and odor of the halogen, the change in the taste of the composition to which it is mixed, the total basic pH, the relatively short duration of the disinfectant activity and the simultaneous sensitivity of the resulting combinations to temperature. In addition, these substances are carcinogenic and mutagenic, cause skin inflammation and are corrosive to various materials.

Ozone and chlorine dioxide merge to form a particularly fast and effective disinfectant, but the resulting combination is potentially explosive. These combination agents can also be very dangerous in large doses. In addition, they exhibit temperature sensitivity, are prone to carcinogenicity and mutagenicity and require careful handling and expensive ancillary equipment. Therefore, they are only suitable for a very narrow scope.

Copper salts, especially copper sulphate and copper chloride, are recommended as odorless, non-irritating mucous membranes, etc. These preparations, which give only an average, short-term disinfectant rate and are known as carcinogens and mutagens, can be easily combined with other substances, including chloride salts.

A process that is normal, odorless, and has no adverse health effects, i.e. the Catadyne method; a similar method uses the disinfecting effect of silver ions. The second of these two processes is slow and has limited utility due to its high cost.

Ultraviolet radiation, which does not introduce a foreign substance into the substance to be disinfected, is a reliable source of disinfectant. The production of ultraviolet radiation, however, requires expensive equipment and the considerable cost is commensurate with the great need for electricity.

Other commercially available products rely heavily on the strong disinfectant effect of hydrogen peroxide, but due to their instability, such preparations have limited utility. Med te l

preparations also include those that combine the well-known disinfectant effects of silver with hydrogen peroxide in the form of a stable agent to produce synergism between the two disinfectants. Description of solution to a technical problem with implementation examples

As a result of the present invention, it is now possible to produce, by means of a new process, products of the type just mentioned, which have significantly improved quality and usefulness.

Smoter! The present invention is to provide a manufacturing process

I is a clear, stable concentrate that can be mixed with hydrogen peroxide to produce a disinfectant, containing silver, inorganic acid and an organic stabilizer.

It is a further object of the present invention to provide a concentrate of this type as well as a process for preparing a disinfectant from such a concentrate.

The present invention is a stable concentrate containing a silver compound, an inorganic acid and an organic stabilizer, and a process for its preparation and use. The concentrate is intended to be mixed with hydrogen peroxide to form a disinfectant.

According to the present invention, a clear stable concentrate can be prepared which can be mixed with hydrogen peroxide to obtain a disinfectant by mixing a solution of aqueous inorganic acid with a pH less than or equal to 1.6 in deionized water between 50 and 60 ° C with a silver salt or complex silver salts in an amount of about 95 to 105 g Ag per liter, wherein the amount of acid present is at least equimolar with the silver salt present or the silver salt complex; by cooling the resulting aqueous acid solution between 25 and 30 ° C and adding an organic acid stabilizer and optionally gelatin.

Suitable silver compounds include silver nitrate (AgNO ^), silver sulfate (Ag ^ SO ^), silver chloride (AgCl), and the sodium and silver chloride complex having the formula AgNaCl ^. Additional suitable silver compounds are silver benzoate (C ^ H ^ -CO ^ Ag), silver carbonate (Ag ₂ C0.p, silver fluoride (AgF), silver / I / oxide (Ag ₂ 0), and silver / II / oxide ( One or more silver compounds are added in such quantities that it contains a concentrate of 100 g + 5% silver per liter of concentrate.

Alternatively to the use of silver salt or the silver salt complex, colloidal silver may be used. This procedure is carried out by adjusting the aqueous solution containing about 13 g of colloidal silver per liter with inorganic acid to pH - 1.6, warming the solution to 50 to 60 ° C, mixing with the organic stabilizer solution in distilled or completely demineralized water. at about the same temperature in such quantity as to be

- 4 a concentration of silver of about 9.5 to 10.5 g Ag per liter of water, the mixture is added at a temperature of 20 to 25 C such that the amount of inorganic acid used to adjust the pH is such that the total amount of inorganic acid is at least equimolar with the amount of silver present , the solution is optionally mixed with gelatin and homogenized.

A suitable colloidal silver compound obtainable from Degusse AG, Zurich, contains 13 g of silver per liter in an aqueous solution of 5% by weight non-polyhydroxyl monocarboxylic acid.

Tartaric acid and / or citric acid are suitable stabilizers for use in combination with a silver component (silver components). These acids should be added in an amount of about 50 g of one and / or the other per liter of concentrate.

Q> Given suitable organic-acid stabilizers to be used in stoichiometric quantities equivalent to those indicated for the incorporation of tartaric and / or citric acids include acetamidoacrylic acid (H ₂ C = C (NHC0CH ^) C0 ₂ H) , acetamidohexanoic acid (CH-, C0NH (CH „) _[ -C0„ H), acetylbutyric acid (CH ^ C0 (CH ₂ ) ^ COpH), acrylic acid (H ₂ C = CHCO ₂ H), adipic acid (HO ₂ C (CH ₂ ) CO ₂ H), maleic acid (HO ₂ CCH ₂ CH (OH) CO ₂ H), ethoxyacetic acid (C ₂ Hg0CH ₂ C0 ₂ H), formic acid (HCO ₂ H), succinic acid (HO ₂ CCH ₂ CH ₂ CO ₂ H), butyric acid (CHgCH ₂ CH ₂ CO ₂ H), hexanoic acid (CHg (CH) ₂ CO ₂ H), hypuric acid (C ₆ H ₅ CONHCH ₂ CO ₂ H), malonic acid (H0 ₂ CCH ₂ C0 ₂ H), methanesulfonic acid (CHgSOgH), lactic acid (CH ₃ CH (OH) CO ₂ H), caprylic acid (CHg (CH ₂ ) ₆ CO ₂ H), oleic acid (CHgiCH ^ CH), oxalic acid (H0 ₂ CC0 ₂ H), salicylic acid (HOC ^ H ^ CC ^ H) and valeric acid (CHg (CH ₂ ) gC0 ₂ C ₂ Hg). Although each of the above organic acids is suitable for use with both silver salts and colloidal silver preparations, they are particularly suitable for use with different silver salts. However, tartaric and / or citric acid are most preferred for use with silver salt compounds.

Although each of the above organic acid stabilizers is suitable for use in combination with colloidal silver, the following acetonecarboxylic acid (HO ₂ CCH ₂ COCH ₂ CO ₂ H), acetoxybenzoic acid (ΟΗ ^ ΟΟ) is preferred for use in amounts of about 100 g per liter of concentrate. ^^ Η ^ ΟΟ ^), ethoxybenzoic acid (C ^ HgOCgH ^ CO ^), ethylbenzoic acid (C ^ HgCgHjjCO ^), aminobenzoic acid (Η ₂ Ν0θΗ ^ 00 ₂ Η), benzoic acid (CgHgC0 ₂ H), bromoacid (BrC ^ H ^ CO ^), bromosalicylic acid (BrCgHg-2- (0H) C0 ₂ H), fluorosulfonyl-benzoic acid (FS0 ₂ CgH ^ C0 ₂ H), hydroxybenzoic acid (H0CgH _i | C0 ₂ H) and phthalic acid (C ^ H ^ -I, 2- (C0 ₂ H) ₂ ).

Although preferred for use with colloidal silver, the most preferred are stabilizers from various

- 6 benzoic acids, these organic acid stabilizers can also be used with the silver salts mentioned above.

Inorganic acid is used to reduce the pH of the preparation containing silver and stabilizer. Generally 75% aqueous phosphoric acid, 65% aqueous nitric acid or 69% aqueous sulfuric acid are used. Hydrochloric acid, hydrochloric acid or boric acid are equally suitable. It is advisable to use the same acid as will be used later to stabilize the commercially available hydrogen peroxide mixed with the concentrate. The acid is used as a pH regulator but also acts as an additional stabilizer for the silver compound and for the ready-to-use product. For this reason, acid should be added in excess of the amount required to adjust the pH. The total amount of acid in the concentrate obtained is at least equimolar with the amount of silver present, and preferably in excess, e.g. 100 g of acid per liter of concentrate.

If the concentrate, after being mixed with hydrogen peroxide to produce a ready-made disinfectant, will be exposed to UV radiation for a long time, e.g. sun radiation, etc., as in the case of an outdoor swimming pool, it is advisable to add gelatin to the concentrate at at least 20 ° C before homogenizing; in general, this additive amounts to about 20 g per liter of concentrate and protects silver from the effects of UV radiation.

It is advantageous to prepare the concentrate at a temperature of at least 20 ° C and under a red light until the bottling is complete,

- 7 e.g. in colored glass containers or plastics without pigment.

The durability of the concentrate of the present invention is unlimited, even at tropical temperatures, and, unlike the well-known products, remains an aqueous, clear, colorless, homogeneous liquid that does not thicken for extended periods of time. This permanent homogeneity of the product is an important advantage because it allows for the possible future dosage of concentrate portions without the re-homogenization that was required until the present invention was developed.

The concentrate obtained with the silver salt or the silver salt complex can be mixed with 35 to 50 wt. % hydrogen peroxide (in water) in a volume ratio of 1:99 to 1: 199If a concentrate containing colloidal silver is used in the quantities defined above, mixing with hydrogen peroxide is carried out at a ratio of 1: 9.9 to 1:19. 9. The ready-to-use product obtained has an Ag concentration between 0.05 and 0.1% by weight. At a ratio above 1: 199 oz. Above 1: 19.9 loses product of silver / hydrogen peroxide synergy characteristics. At a ratio of less than 1:99 respectively. 1: 9,9 there is a possibility that silver will precipitate from the mixture. The product, which is within the limits mentioned above, has been in storage for at least 2 years.

The concentration of hydrogen peroxide added can easily be up to 30% by weight for certain applications. %, however, the product decomposes more rapidly and the rate of disinfection is less than that obtained by the use of 50 wt. of hydrogen peroxide.

Due to the stable homogeneity of the concentrate, it is not necessary to re-homogenize the concentrate before mixing it with hydrogen peroxide.

Disinfectants of this type, mixed with hydrogen peroxide and ready for use, can then be bottled in conventional containers for transport and sale, which should be equipped with a safety device to reduce any excess gas pressure, e.g. with safety valve. Chemical agents can remain in such containers at a temperature between 4 and 25 ° C for about 2 years without any danger. Longer storage is not recommended at higher temperatures as carbon dioxide tends to release gas.

The disinfectants we have invented are suitable for sterilizing water, food and animal feed, stationary surfaces, etc. The concentrate is added in very small amounts, generally about 10 to 75 ppm, when added as a t.i. a disinfectant for things such as bathing water, drinking water, food, cooking water, etc., or used as 0.1 to 2 wt. % solution for surface disinfection. With these new agents, disinfected products or objects show absolutely no change in odor, taste or appearance, are non-toxic, cause neither skin inflammation nor other damage to health or damage, and are completely inert with conventional materials such as concrete, wood, stone , glass, metals, porcelain, ceramics, plastics, fabrics, etc.

The ready-to-use agent has a pH of about 2 and should be adjusted to that pH if necessary, preferably by adding an additional amount of inorganic acid already present in the preparation.

Unlike chlorine, the agent itself does not change the pH of the product to which it is added, mainly because only small amounts need to be used. It can also be used in a wider temperature range than chlorine, namely between 0 and 95 ° C, and the disinfectant effect increases with increasing temperature.

At the concentrations above, new agents are largely capable of destroying pathogenic germs. Among others, Gram-positive and Gram-negative bacteria, bacteriophages, viruses, etc. are suppressed. such as E. coli, Proteus mirabilis, Staphylococcus aureus, Streptococcus faecalis, Pseudomonas aeruginosa, Mycobacteri tuberculosis, Candida albicans, etc.

The new agents are particularly suitable for sterilization in the food and animal feed industries, including the canning industry, for the canning of fresh produce, for the processing of fish for partial or total canning, and for disinfection in slaughterhouses, the beverage industry and breweries, for the preparation of mineral water , in the production of wine and spirits, in the production of fruit and vegetable juices, for the disinfection of bottles and crates, and in water to be added to concentrates, in the disinfection of drinking water in wells or storage vessels, in swimming pools and in hot vortices as well as in dairies, agriculture, chemical and pharmaceutical industries, laboratories and hospitals, disease control, etc.

In the following cases, all percentages refer to mass unless otherwise stated.

EXAMPLE 1

At above 20 ° C and under the red light, 75% phosphoric acid was slowly added and mixed in 0.8 l of fully demineralized water until the pH was equal to or less than 1.6. The mixture was stirred and heated to 55 ° C and added while stirring

157.5 g of silver nitrate. Stirring was continued until complete homogenization.

The solution was allowed to cool to about 25 to 30 ° C; the 75% phosphoric acid was then slowly mixed in so that the total amount of phosphoric acid (75%) was 100 g in the solution. The mixture was then allowed to reach room temperature (20 to 25 ° C) without stirring, then 50 g of tartaric acid were added.

The resulting mixture was then brought to a total volume of 1 L with the addition of distilled or fully deionized water, adjusted to pH equal to or less than 1.6 with the same inorganic acid, if necessary, and then homogenized, in this particular case after the addition of 20 g of gelatin it was stirred at a temperature in excess of 20 ° C. A crystal clear solution was obtained. The same result would be achieved if 65% nitric acid or 37% hydrochloric acid or 69% sulfuric acid were added instead of phosphoric acid to a total addition of 100 g of acid, and / or if silver nitrate was replaced with 145 g of silver sulfate or 137 g of silver chloride or 187.2 g of the sodium / silver chloride complex (AgNaCl ₂ ), and / or 50 g of citric acid or 50 g of a mixture of citric acid and tartaric acid would be used instead of tartaric acid.

1

EXAMPLE II

For the preparation of 11 l of concentrate, 850 g of sodium or potassium benzoate was slowly and slowly added to 1 l of distilled water at rations at about 55 ° C. The stirring was then stopped and the mixture was stored at 55 ° C.

In a separate container, 75% of phosphoric acid, 65% nitric acid or 69% sulfuric acid of 8350 g of colloidal silver solution (13 g of Ag per liter in a 5% aqueous solution of polyhydroxyl carboxylic acid) were added slowly and in portions. acid from Degussa AG) to obtain a pH of 1.6 or less and heat the mixture to 55 ° C.

To this mixture was then added all the aqueous solution of the above prepared sodium or potassium benzoate, and the mixture was well homogenized. It was then allowed to cool to room temperature (20 to 25 ° C) without stirring. The cooled mixture was then added with stirring to an amount of the same inorganic acid to adjust the pH to a total volume of 800 g; the addition was carried out slowly and after meals while stirring. This resulted in the mixture being well homogenized. Addition of 200 g of gelatin at a minimum of 20 ° C and re-homogenization gave a concentrate which was completely stable against any precipitation or degradation even under ultraviolet irradiation of water, disinfected with the final product, e.g. in swimming pools.

EXAMPLE III

1 of the concentrate obtained according to Example I was mixed at room temperature under a red light and in a stainless steel retort in a volume ratio of 1:99 with 50% by volume H ₂ 0 ₂ until homogenized. When the formation of the bubbles ceased, the product was bottled.

This product was especially suitable for long-term disinfection, especially at high temperatures, e.g. as an additive for hot swirls, recycled water for water treatment plants, etc., preferably in a concentration of 40 to 75 ppm.

EXAMPLE IV

1 concentrate obtained in accordance with Example II was processed similarly to Example III in a ratio of 1: 19.9 with 50% by volume H ₂ 0 ₂ to the final product. The product obtained is suitable e.g. for the disinfection of drinking water at a concentration of 10 to 34 ppm, and for the disinfection of surfaces in a 0.1 to 2% solution.

Although the invention has been described with reference to specific methods and materials, the invention should be limited only to the extent stated in the appended claims.

- <The best way to make economic use of the invention

At above 20 ° C and under the red light, 75% phosphoric acid was slowly added and mixed in 0.8 l of fully demineralized water until the pH was equal to or less than 1.6. The mixture was stirred and heated to 55 ° C and 157.5 g of silver nitrate was added while stirring. Stirring was continued until complete homogenization.

The solution was allowed to cool to about 25 to 30 ° C; the 75% phosphoric acid was then slowly mixed in so that the total amount of phosphoric acid (75%) was 100 g in the solution. The mixture was then allowed to reach room temperature (20 to 2d5 ° C) without stirring, then 50 g of tartaric acid were added.

The resulting mixture was then brought to a total volume of 1 L with the addition of distilled or fully deionized water, adjusted to pH equal to or less than 1.6 with the same inorganic acid, if necessary, and then homogenized, in this particular case after the addition of 20 g of gelatin, which it was stirred at a temperature in excess of 20 ° C. A crystal clear solution was obtained.

For

SANOSIL AG .:

PATENT APPLICATIONS

A process for the preparation of a disinfectant concentrate which is clear, unlimited storage stability and which, after mixing with hydrogen peroxide, is a disinfectant containing silver, inorganic acid and an organic stabilizer, according to variant I, characterized in that the distilled or completely demineralised water which is adjusted to pH less than or equal to 1.6 with inorganic acid, mixed with silver salt or its complex at a temperature of about 95 to 105 g Ag per liter of water at a temperature of 50 to 60 ° C, and the mixture mixed with acid at 25 to 30 ° C used to adjust the pH to such an extent that the total amount of this acid is at least equimolic with the silver component present, the resulting solution at 20 to 25 ° C is mixed with an organic stabilizer and optionally homogenized after the gelatin is added.

Process according to claim 1 according to variant II, characterized in that the aqueous solution containing about 13 g of colloidal silver per liter is adjusted with inorganic acid to pH <1.6, the solution is heated to 50 to 60 ° C, mixed with a solution of organic stabilizer in distilled or fully demineralized water at about the same temperature in such a quantity that the silver concentration is about 9.5 to 10.5 g Ag per liter of water, the mixture is added at a temperature of from 20 to 25 ° C such an amount of inorganic acid, used to adjust the pH so that the total amount of inorganic acid is at least equimolic with the amount of silver present, the solution is optionally mixed with gelatin and homogenized.

Process according to claim 1 or 2, characterized in that phosphoric, nitric or sulfuric acid, preferably in an amount of 100 g per liter of water, is used as an inorganic acid.

A process according to claim 1, characterized in that silver nitrate, sulfate or chloride or sodium-silver chloride complex and the tartaric and / or citric acid, preferably in an amount of about 50 g per liter of water, are used as the silver salt.

Process according to claim 2, characterized in that colloidal silver in an aqueous solution containing about 5% by weight of polyhydroxymonocarboxylic acid is added and alkali benzoate is used as the organic stabilizer.

Process according to one of Claims 1 to 5, characterized in that the mixing begins at at least 20 ° C.

Process for the preparation of a disinfectant, characterized in that at a temperature of at least 20 ° C and, optionally, under the red light, the concentrate prepared in accordance with the method of claim 1 with 35 to 50% by volume aqueous hydrogen peroxide in the ratio of concentrate to aqueous hydrogen peroxide is 1:99 and 1: 199, whereby the resulting preparation has an Ag concentration between 0.05 and 0.1% by weight.

Process for the preparation of a disinfectant, characterized in that at a temperature of at least 20 ° C and, optionally, under the red light, the concentrate prepared in accordance with the process of claim 2 with 35 to 50% by volume aqueous hydrogen peroxide in the ratio of concentrate to aqueous hydrogen peroxide is 1: 9.9 and 1: 19.9, with the resulting preparation having an Ag concentration between 0.05 and 0.1% by weight.

For

SANOSILAG .:

b

20057-III-91 / PR

Claims (1)

SUMMARY OF THE DESCRIPTION A concentrate of unlimited storage duration, which can be mixed with hydrogen peroxide in a ratio of 1:99 to 1: 199 to produce an effective disinfectant, is obtained by mixing a viscous inorganic acid solution with a pH less than or equal to 1.6 with silver salt compound at 50 to 60 ° C. The mixture is further added at room temperature to another inorganic acid (other inorganic acids) to achieve a total of 100 g of inorganic acid (inorganic acids) per liter of water, an organic acid stabilizer is added at room temperature and the mixture is homogenized. The concentrate remains homogeneous and crystal clear during storage. Instead of a silver compound, colloidal silver can be used; the ratio of the concentrate obtained with this silver to hydrogen peroxide is 1: 9.9 to 1: 19.9.