Pipe cleaning composition

Abstract

The present invention refers to pipe cleaning compositions comprising sulfuric acid, sulfonic acid and low concentrations of water, as well as methods of cleaning a pipe by using the compositions, as well as the use of the compositions in a method of cleaning and / or unclogging a clogged pipe.

Description

[0001] The present invention relates to pipe cleaning compositions comprising sulfuric acid, a sulfonic acid and wherein the composition comprises low amounts of water as defined in the claims. The invention further relates to methods of cleaning a pipe, the method involving the addition of the composition as defined in the claims, as well as the use of the compositions in methods of cleaning a pipe as defined in the claims.Technical background

[0002] Pipes, drains and traps in the kitchen or bath can often be blocked or slowed by buildup of organic and / or inorganic matter, such as grease, soap, hair, or food waste in combination with e.g. cellulosic materials. Such organic blockage or partial blockage can be cleared mechanically or chemically with a variety of different trap and drain cleaners including concentrated acids or alkalis, oxidizing agents, and foaming or non-foaming combinations of these cleaners or biological systems.

[0003] Pipe cleaning compositions are specialized chemical solutions formulated to remove obstructions and clean the internal surfaces of pipes. These compositions are essential in preventing and addressing clogs, thereby ensuring the smooth operation of plumbing systems in residential, commercial, and industrial environments. Among various types of pipe cleaners, acid-based formulations are particularly effective in breaking down organic and inorganic materials.

[0004] Acid-based pipe cleaning compositions primarily utilize strong acids to dissolve blockages. These compositions are highly effective against a wide range of clogs, including those caused by hair, soap scum, grease, and mineral deposits. The acids commonly used in these cleaners include hydrochloric acid, sulfuric acid, and phosphoric acid. Each of these acids offers unique properties that make them suitable for different types of pipe cleaning applications.

[0005] Sulfuric acid (H 2 SO 4 ) is a prominent ingredient in many high-strength pipe cleaning formulations due to its potent chemical properties. It is a highly corrosive, dense, oily liquid that can effectively break down organic materials such as hair, grease, and paper products. The mechanism by which sulfuric acid cleans pipes involves several key reactions: 1. Hydrolysis: Sulfuric acid reacts highly exothermic with water to produce hydronium ions (H 3 O +< ) and bisulfate ions (HSO 4 -< ), which are highly reactive. 2. Oxidation: The acid acts as an oxidizing agent, breaking down complex organic molecules into simpler compounds, which are then easier to wash away. 3. Dehydration: Sulfuric acid has a strong affinity for water, and it can dehydrate organic materials, effectively reducing them to carbon and water vapor.

[0006] The efficacy of sulfuric acid in pipe cleaners is enhanced by its ability to generate heat upon contact with water, which can help to melt fats and other semi-solid blockages.

[0007] While sulfuric acid-based pipe cleaners are highly effective, they must be used with caution. The corrosive nature of sulfuric acid poses significant safety risks, including chemical burns and respiratory hazards. Proper personal protective equipment (PPE), such as gloves and goggles, should be worn when handling these products. Additionally, these cleaners should be used in well-ventilated areas to avoid inhalation of fumes.

[0008] Sulfuric acid-based pipe cleaning compositions are a powerful solution for clearing severe blockages in plumbing systems. However, their ability to rapidly dissolve organic materials and generate heat can hamper dissolution of clogging materials which is required for residue-free dissolution and the full restoration of the functionality of pipes.

[0009] DE 100 36 607 A1 discloses the use of acid preparations for cleaning and / or disinfecting hard surfaces, as well as a method for cleaning and disinfecting installations, further to corresponding acid cleaning and / or disinfecting agents containing, in relation to the whole agent, a) 1 to 95 w% of at least one acid chosen from phosphoric acid, alkanesulfonic acid, nitric acid and sulphuric acid, and b) 1 to 40 w% of un-decylenic acid, the remainder which completes the 100 w% being water and / or other auxiliary agents and / or active ingredients. US 8,188,025 B2 discloses acidic sanitizing and / or cleaning compositions comprising a specific quaternary antimicrobial system consisting of C1-C4 hydroxyalkyl carboxylic acids, C5-C18 alkyl monocarboxylic acids, unsubstituted or substituted, saturated or unsaturated C4-dicarboxylic acids and additional inorganic or organic acids. EP 3 228 688 B1 discloses liquid acidic hard surface cleaning composition comprising certain copolymers that provide good limescale removal and long lasting shine to a broad range of surfaces, furthermore, when formulated with suitable acid systems, they also provide improved surface safety over more delicate surfaces. WO 2017 / 007416 A1 discloses acid detergent compositions, concentrates and use solutions prepared from the concentrates and methods of using the same, wherein the acid detergent compositions are particularly suited for use in removing soils, especially milk soils, from clean-in-place systems, such as those commonly used in the dairy and food processing industries, wherein the detergent compositions comprise an acidic component including an inorganic or alkanesulfonic acid and a blend of surfactants to provide high cleaning efficiency and low foam generation, wherein the acid detergent compositions optionally comprise an antimicrobial agent to impart a sanitization functionality to the detergent.Summary of the invention

[0010] The inventors have realized the need for an improved pipe cleaning composition, wherein, in particular, the dissolving capacity is increased, in particular towards cellulose-based components, and the dissolving properties of the compositions can be fully utilized.

[0011] In one aspect according to the present disclosure, there is provided a pipe cleaning composition comprising: sulfuric acid in an amount of from 5 to 30% by weight of the composition, a sulfonic acid in an amount of from 40 to 95% by weight of the composition, wherein the amount of total water in the composition is less than 20% by weight of the composition.

[0012] In a further aspect according to the present disclosure there is provided a method of cleaning a pipe, the method comprising: a) adding a pipe cleaning composition comprising sulfuric acid in an amount of from 5 to 30% by weight of the composition and sulfonic acid in an amount of from 40 to 95% by weight of the composition into a pipe, and b) flushing the pipe with a liquid, preferably water, after adding the cleaning composition.

[0013] In a further aspect according to the present disclosure there is provided the use of a composition as defined in the claims in a method of cleaning and / or unclogging a soiled and / or clogged pipe, preferably for use in a method cleaning and / or unclogging a clogged pipe, wherein the pipe is soiled and / or clogged essentially by a cellulose-comprising material.Brief description of the drawings

[0014] Figure 1 shows the effect of sulfuric acid, methanesulfonic acid and mixtures thereof in varying ratios on sanitary tampons at different reaction times. Figure 2 shows the degree of charring (dark grey) and the degree of dissolution (light grey) of sanitary tampons by sulfuric acid, methanesulfonic acid and mixtures thereof. Figure 3 shows the observed temperature profile from the dissolution / addition of various MSA / H 2 SO 4 mixtures to / with water as compared with expected values. Detailed description of the invention

[0015] Surprisingly, the present inventors found that pipe cleaning compositions comprising: sulfuric acid in an amount of from 5 to 30% by weight of the composition, a sulfonic acid in an amount of from 40 to 95% by weight of the composition, and wherein the amount of total water in the composition is less than 20% by weight of the composition as defined in the claims provide dissolving and thus cleaning properties which are significantly enhanced. Examples 1 and 2 show the physical and chemical properties of the compositions of the present invention when used for pipe cleaning applications, exemplified, in particular, by the dissolution of cellulose-based components. Cellulose-based materials that can soil and / or clog pipes (e.g. in households) include but are not limited to sanitary pads, sanitary napkins, sanitary tampons etc.

[0016] The term "pipe cleaning composition" as used herein refers to any formulated composition, mixture, product, or solution designed to maintain, restore, or enhance the functionality of plumbing systems by removing obstructions, dissolving build-ups, and preventing future blockages within pipes. These compositions achieve their purpose through various mechanisms, including chemical reactions, biological processes, or mechanical actions, tailored to address specific types of clogs and pipe materials. In principle, the term refers to cleaning compositions which are particularly suitable for cleaning applications in pipes and / or pipe systems, such as the opening of (clogged and / or soiled) drains, wherein the pipes can be of various inorganic, organic or mixtures of inorganic and organic materials, including, metal, glass, ceramic, plastic, polymeric material, composites etc.

[0017] The pipe cleaning compositions comprise sulfuric acid in an amount effective to provide the desired cleaning properties. Sulfuric acid can be present in an amount of from 5 to 30% by weight of the composition. Sulfuric acid can be present in an amount of from 7.5 to 20% by weight of the composition, preferably from 10 to 17% by weight of the composition, further preferably in an amount of from 12 to 15% by weight of the composition. Sulfuric acid can be present in an amount of about 14 to 15% by weight of the composition, such as 14.2 to 14.8%, 14.3 to 14.7%, 14.4 to 14.6%, most preferably about 14.4% by weight of the composition. The weight% of sulfuric acid as referred to herein and as defined in the claims refer to the amount or concentration of pure sulfuric acid, that is, without water (i.e. non-aqueous). That is, in order to provide a compositions comprising 14.4 weight% sulfuric acid, 15.0 weight% of a 96% sulfuric acid solution can be used.

[0018] A compositions comprising sulfuric acid in a concentration as above can provide excellent dissolution properties, in particular with respect to cellulose-based materials, without yielding excessive and / or potentially dangerous temperature peaks or resulting in carbonization or charring or clogging materials.

[0019] Sulfuric acid can be added as a solution of pure sulfuric acid in water, for example as a solution of 99%, 98%, 97% or 96% pure sulfuric acid in water (i.e. "concentrated sulfuric acid"). Sulfuric acid may contain not only H 2 SO 4 molecules, but can actually be an equilibrium of many other chemical species, as exemplified in the following: HSO 4 -< (15.0 mMol / kg), H 3 SO 4 +< (11.3 mMol / kg), H 3 O +< (8.0 mMol / kg), HS 2 O 7 (4.4 mMol / kg), H 2 S 2 O 7 (3.6 mMol / kg), H 2 O (0.1 mMol / kg). As noted above, in order to provide a compositions comprising 14.4 weight% sulfuric acid, 15.0 weight% of a 96% sulfuric acid solution is added. Similarly, in order to provide a compositions comprising 14.7 weight% sulfuric acid, 15.0 weight% of a 98% sulfuric acid solution can be used.

[0020] The pipe cleaning compositions also comprise a sulfonic acid in an amount effective to provide the desired cleaning properties. The sulfonic acid can be present in an amount of from 40 to 95% by weight of the composition. The sulfonic acid can be present in an amount of from 50 to 90% by weight of the composition, preferably from 65 to 87.5% by weight of the composition, further preferably in an amount of from 80 to 85% by weight of the composition. Sulfonic acid can be present in an amount of about 82 to 83%, about 82.2 to 82.8%, about 82.3 to 82.5%, most preferably in an amount of about 82.4% by weight of the composition.

[0021] A compositions comprising sulfonic acid in a concentration as above in combination with sulfonic acid can provide excellent dissolution properties, in particular with respect to cellulose-based materials, without yielding excessive and / or potentially dangerous temperature peaks or resulting in carbonization or charring or clogging materials.

[0022] The term "sulfonic acid" as used herein refers to a member of the class of organosulfur compounds with the general formula R-S(=O) 2 -OH, where R is an organic alkyl group or aryl group and the S(=O) 2 (OH) group a sulfonyl hydroxide. The alkyl group can be linear or branched. The alkyl group can be substituted or unsubstituted. The alkyl group can comprise from 1 to 8 carbon atoms, preferred are 1 to 6 carbon atoms, further preferred from 1 to 3 carbon atoms, further preferably one carbon atoms (methanesulfonic acid). The aryl group can be saturated or unsaturated. The aryl group can be substituted or unsubstituted. The aryl group can comprise from 5 to 8 carbon atoms, preferred are 5 to 6 carbon atoms, further preferably 6 or 7 carbon atoms (p-toluenesulfonic acid or benzenesulfonic acid). As a substituent, it is also known as a sulfo group. A sulfonic acid can be described also as sulfuric acid with one hydroxyl group replaced by an organic substituent. The parent compound (with the organic substituent replaced by hydrogen) is the parent sulfonic acid, HS(=O) 2 (OH), a tautomer of sulfurous acid, S(=O)(OH) 2 . The term "about" as used herein refers to all values within + / - 10% of the respective value, that is, the expression 'about 1' refers to all values of from 0.9 to 1.0, preferably to all values within + / - 5% of the respective value, that is, the expression 'about 1' refers preferably to all values of from 0.95 to 1.05, further preferably to all values within + / - 1% of the respective value, that is, the expression 'about 1' refers to all values of from 0.99 to 1.01.

[0023] The sulfonic acid can comprise one or more selected from the group consisting of methanesulfonic acid (MSA), ethanesulfonic acid (ESA), benzenesulfonic acid (BSA), p-toluenesulfonic acid (p-TSA), camphorsulfonic acid (CSA), naphthalenesulfonic acid (NSA), dodecylbenzenesulfonic acid (DBSA), 2-naphthalenesulfonic acid (2-NSA), styrenesulfonic acid (SSA), 4-aminobenzenesulfonic acid (4-ABS), preferably one or more selected from the group consisting of methanesulfonic acid (MSA) ethanesulfonic acid (ESA), benzenesulfonic acid (BSA), and p-toluenesulfonic acid (p-TSA), further preferably the sulfonic acid comprises methanesulfonic acid (CH 4 O 3 S).

[0024] The sulfonic acid can comprise at least 70% by weight of methanesulfonic acid based on the amount of sulfonic acid, wherein the remaining amount of sulfonic acid is selected from the group of water, further sulfonic acids, stabilizers, further additives or combinations thereof. The sulfonic acid can comprise at least 80% by weight of methanesulfonic acid based on the amount of sulfonic acid at least 85% by weight of methanesulfonic acid based on the amount of sulfonic acid at least 90% by weight of methanesulfonic acid based on the amount of sulfonic acid at least 95% by weight of methanesulfonic acid based on the amount of sulfonic acid. In some embodiments the sulfonic acid is methanesulfonic acid. As discussed for the sulfuric acid, the weight% of the sulfonic acid (e.g. methanesulfonic acid) as referred to herein and as defined in the claims refer to the amount or concentration of pure sulfonic acid (e.g. methanesulfonic acid), that is, without water (i.e. non-aqueous). That is, in order to provide a compositions comprising 82.4 weight% methanesulfonic acid, 83.2 weight% of a 99.5% methanesulfonic acid solution can be used (e.g. Lutropur MSA 100 ®< by BTC Europe GmbH).

[0025] The total amount of water in the composition is less than 20% by weight of the composition. The total amount of water in the composition can be less than 20%, less than 15%, less than 10%, less than 7.5%, less than 5%, or less than 2.5% by weight of the composition. In some embodiments, the total amount of water in the composition is about 2.4% by weight of the composition or less such as 2% by weight or less, 1.5% by weight or less etc.

[0026] A compositions comprising concentrations of water as above can provide excellent dissolution properties, in particular with respect to cellulose-based materials while providing also a controlled temperature increase while applied to clean and / or unclog drains or pipes wherein water molecules are present which result in an exothermic protonation.

[0027] The composition can further comprise a corrosion inhibitor, preferably an organic corrosion inhibitor, further preferably an organic corrosion inhibitor selected from the group consisting of substituted or unsubstituted alcohol amines or salts thereof, further preferably the composition further comprises the corrosion inhibitor 2,2',2"-nitrilotrisethanol 6-[(3,5,5-trimethyl-1-oxohexyl)amino]hexanoate salt. In some embodiments, the corrosion inhibitor in the composition is 2,2',2"-nitrilotrisethanol 6-[(3,5,5-trimethyl-1-oxohexyl)amino]hexanoate salt (e.g. CAS 242482-67-3).

[0028] The corrosion inhibitor can be present in an amount of from 0.1 to 2.0% by weight of the composition, preferably in an amount of from 0.2 to 1.0% by weight of the composition, further preferably in an amount of from 0.4 to 0.6% by weight of the composition. Most preferably, the corrosion inhibitor is 2,2',2"-nitrilotrisethanol 6-[(3,5,5-trimethyl-1-oxohexyl)amino]hexanoate salt and present in an amount of about 0.5% by weight of the composition.

[0029] The addition of corrosion inhibitors as above can provide excellent corrosion protection of steel, a reduction of copper and cobalt leaching, low foaming, the corrosion inhibitors can be hard-water stable, can be boron free etc. The addition of such corrosion inhibitors can provide compositions which are highly effective in the dissolution of specific organic compounds (such as cellulose from sanitary pads, sanitary napkins, sanitary tampons etc.), while corrosion of the pipes or drains to be cleaned is avoided.

[0030] The composition can further comprise a cationic, anionic, amphoteric or neutral surfactant, preferably a cationic surfactant, further preferably a quaternary ammonium surfactant, further preferably an alkyldimethylbenzylammonium chloride surfactant, further preferably the composition comprises, preferably consists of, the cationic surfactant benzyl C12-C14 alkyl dimethylammonium chloride, benzyl C12-C16 alkyl dimethylammonium chloride (e.g. CAS 68424-85-1), or combinations thereof.

[0031] The cationic surfactant can be present in an amount of from 0.05 to 1.0% by weight of the composition, preferably in an amount of from 0.1 to 0.5% by weight of the composition, further preferably in an amount of from 0.2 to 0.3% by weight of the composition. In some embodiments, the cationic surfactant is a combination of benzyl C12-C14 alkyl dimethylammonium chloride and benzyl C12-C16 alkyl dimethylammonium chloride and is present in an amount of about 0.24% by weight of the composition.

[0032] The addition of cationic surfactants as above can provide excellent interfacial interaction, thereby allowing penetration of solutions (e.g. water) in materials with generally low water affinity. That is, the addition of such surfactants can provide compositions which are highly effective against and effectively penetrate specific organic compounds (such as cellulose) when these are not highly water-affine and / or contaminated with hydrophobic compounds, such as oils, grease etc.

[0033] The composition can be free from enzymes, ionic liquids, sodium hydroxide, potassium hydroxide, oxidizing agents such as peroxides and chloroxides, ammonia and / or organic solvents. That is, in some embodiments, the composition is free of other components which can be used in (pipe) cleaning composition that might possibly be detrimental from an ecological or an applicability point of view. That is, in some embodiments, the cleaning properties are essentially provided by the combination of sulfuric acid and sulfonic acid. By omitting compounds which are employed in pipe cleaning compositions of the prior art, the present invention allows for a simplified and highly efficient pipe cleaning composition, wherein no side-reaction with potentially detrimental components can occur.

[0034] The pipe cleaning composition can comprise, preferably consist of: a) methanesulfonic acid in an amount of from 82 to 84% by weight of the composition, optionally 82.4% by weight of the composition, b) sulfuric acid in an amount of from 13 to 15% by weight of the composition, optionally 14.4% by weight of the composition c) 2,2',2"-nitrilotrisethanol 6-[(3,5,5-trimethyl-1-oxohexyl)amino]hexanoate salt in an amount of from 0.25 to 1.0% by weight of the composition, optionally 0.5% by weight of the composition d) a mixture of benzyl C12-C14 alkyl dimethylammonium chloride and benzyl C12-C16 alkyl dimethylammonium chloride in an amount of from 0.1 to 1.0% by weight of the composition, optionally 0.24% by weight of the composition e) C12 / C18 alkyl dimethyl amine oxide in an amount of from 0.05 to 0.5% by weight of the composition, optionally 0.09% by weight of the composition; and f) water, preferably in an amount of from 0.5 to 5% by weight of the composition, further preferably in an amount of about 2.4% by weight of the composition.

[0035] In further embodiments, the present invention refers to a method of cleaning a pipe, the method comprising: a) adding a pipe cleaning composition comprising sulfuric acid in an amount of from 5 to 30% by weight of the composition and sulfonic acid in an amount of from 40 to 95% by weight of the composition into a pipe, and b) flushing the pipe with a liquid, preferably water, after adding the cleaning composition.

[0036] As discussed above, the pipes to be cleaned can be of various inorganic, organic or mixtures of inorganic and organic materials, including, metal, glass, ceramic, plastic, polymeric material, composites etc. but are not limited to the same. The step of adding the composition can be performed in one shot or continuously over a certain time frame. The step of adding the composition can be performed by simply pouring the composition into the pipe to be cleaned or can be added with a device, such as injection pumps, pressure washers, drain snakes with release compartments etc., into the material clogging or soiling the pipe.

[0037] After adding the cleaning composition, the pipe can eventually be flushed with a liquid. The flushing step is, however, not essential to the cleaning properties of the composition, i.e. is not essential to carrying out the invention which relates to cleaning and / or unclogging the pipe. The step of flushing the pipe after adding the cleaning composition can also be performed during regular use of the pipe. Flushing the pipe can, however, be necessary in order to remove remaining cleaning composition and or material from the pipe prior to resuming the regular function of the pipe. Flushing the pipe is performed with a liquid in order to remove all remaining components from the cleaning composition or the material which was removed by the cleaning composition. The liquid can depend on the material of the pipe, on the functionality of the pipe etc. In household applications of the cleaning composition, water is preferably used for the flushing step, in particular for environmental reasons.

[0038] The flushing step can be performed within a certain timeframe after adding the cleaning composition. The timeframe generally depends on the specific components and concentrations of the cleaning composition, as well as the pipe (material, volume etc.) and the material (type, density, drying state etc.) which has to be removed by the cleaning compositions. Generally, the flushing can, for example, be performed at any point after adding the cleaning composition but is preferably performed after about 24 hours or less, after about 12 hours or less, after about 8 hours or less, after about 6 hours or less, after about 4 hours or less, after about 2 hours or less, after about 1 hour or less, after about 30 minutes or less.

[0039] In some embodiments, the method further comprises agitating the pipe cleaning composition in the pipe, preferably by using a plunger or by mechanically stirring the cleaning composition. Agitating the composition in the pipe can used to increase the cleaning and / or unclogging effect of the method but is not essential to carrying out the invention. That is, agitating the composition can increase the interfacial interaction of the oxonium ions (H 3 O +< ) that are present when the cleaning composition reacts with water molecules, with the material that soils and / or clogs the pipe. Furthermore, mechanically agitating further introduces additional instability into a material clogging a pipe and can therefore increase the cleaning effect.

[0040] In preferred embodiments, a composition as described above is used in the method of cleaning a pipe. That is, in most preferred embodiments, a cleaning composition comprising, preferably consisting of: a) methanesulfonic acid in an amount of from 82 to 84% by weight of the composition, b) sulfuric acid in an amount of from 13 to 15% by weight of the composition, c) 2,2',2"-nitrilotrisethanol 6-[(3,5,5-trimethyl-1-oxohexyl)amino]hexanoate salt in an amount of from 0.25 to 1.0% by weight of the composition, d) a mixture of benzyl C12-C14 alkyl dimethylammonium chloride and benzyl C12-C16 alkyl dimethylammonium chloride in an amount of from 0.1 to 1.0% by weight of the composition, e) C12 / C18 alkyl dimethyl amine oxide in an amount of from 0.05 to 0.5% by weight of the composition; and f) water is used in the method of cleaning a pipe.

[0041] In further embodiments, the present invention refers to the use of the above compositions and as defined in the claims in a method of cleaning and / or unclogging a soiled and / or clogged pipe, preferably for use in a method cleaning and / or unclogging a clogged pipe, wherein the pipe is soiled and / or clogged essentially by a cellulose-comprising material. In particular cellulose-based material can be a source or trigger of clogged pipes due to its chemical and micro-structure.Figure description

[0042] Figure 1 shows the effect of sulfuric acid, methanesulfonic acid and mixtures thereof in varying ratios on sanitary tampons after 3 minutes (Figure 1a), after 7 minutes (Figure 1b), after 10 minutes (Figure 1c) and after 14 minutes (Figure 1d).

[0043] For the experiments underlying the results shown in Figure 1, a sanitary tampon (Tpn) is placed in a test tube and mixed with 10g of each of the acid mixtures, and the decomposition or charring (discoloration) of the tampon is observed. For better visualization, photos were taken after 3, 7, 10 and 14 minutes. Already after 3 minutes a clear black discoloration can be seen from DD to G (H 2 SO 4 content at 20% -100%). In contrast to this A (0% H 2 SO 4 , 100% MSA; as w%) showed no discoloration after 3 minutes. The following charring rates can therefore be established for the following mixtures can be determined: G = K > I = H = EE > E ≫ DD > D > F > C > B > A .

[0044] The results in Figure 1 thus show that generally, the higher the concentration of the sulfuric acid, the faster and / or more intensive the charring of cellulose-based material proceeds.

[0045] Figure 2 shows the degree of charring (dark grey; with a low degree of charring of about 1 a.u. at 0% H 2 SO 4 as shown by the first measurement point on the left side of the graph) and the degree of overall dissolution (light grey; with a higher degree of dissolution of about 4 a.u. at 0% H 2 SO 4 as shown by the first measurement point on the left side of the graph) of cellulose-based sanitary tampons using sulfuric acid, methanesulfonic acid and mixtures thereof in varying ratios after 15 minutes. A value of '0' on the y-axis is indicating no dissolution of the sanitary tampon, a value of '6' on the y-axis is indicating a complete dissolution of the sanitary tampon.

[0046] Solutions of highly concentrated sulfuric acid (e.g. 40% to 100% sulfuric acid of a 96% sulfuric acid; CAS 7664-93-9) show a high level of charring. When decreasing the concentration of sulfuric acid, starting at about below 40% sulfuric acid, the level of charring decreases and reaches a minimum at below 15% sulfuric acid.

[0047] Furthermore, the overall dissolution shows a distinct maximum at from about 5 to 20% sulfuric acid in the solution. At lower and at higher sulfuric acid concentrations, the overall dissolution is reduced. Sulfuric acid concentrations of about 5% to about 20% when combined with about 95% to about 80% methanesulfonic acid (and minor concentrations of optional further components) thus provide a sweet spot with respect to the overall dissolution of cellulose-based materials.

[0048] Figure 3 shows the temperature resulting from dissolving acid mixtures in water (with a range from 10 - 80% H 2 SO 4 as shown on the x-axis) which behaves constantly at a temperature of dT Max (10 -80%) = 6.5 +-1.8 °C while samples 'A' and 'G' show a higher dT Max . This means that independent of the MSA / H 2 SO 4 mixing ratio for the 10 - 80% range, the dT Max values do not change. This is very unexpected as dT Max should increase with increasing w% H 2 SO 4 . That is, a linear dependence from the w% H 2 SO 4 is expected with the formula dT Max (w%H 2 SO 4 ) = 7*w% + 14°C (see expected dT Max (fresh-2d) values in Table 4). The x-axis shows the weight percentage ('w%' or 'wt%' or '% by weighty' of sulfuric acid in the acid mixture, the y-axis show the difference in maximum temperatures between a freshly mixed solution and a solution left at room temperature (RT) for 48 hours (i.e. dT Max (w%H 2 SO 4 ) = (T Max , fresh (w%) - T Max , 2d (w%)). The measurement points of acid solutions A (H 2 SO 4 content (w%) = 0%) and G (H 2 SO 4 content (w%) = 100%) are specially marked by encircling the measurement points. There is no clear trend for a higher temperature difference depending on the H 2 SO 4 content (w%), contrary to expectations.Examples Example 1 - Charring / carbonization and dissolution of sanitary tampons

[0049] In the experiments of Example 1, the dissolution properties of various compositions comprising sulfuric acid and / or methanesulfonic acid regarding cellulose-based materials was assessed. As discussed above, sulfuric acid is known for its hydrophilic properties. When sulfuric acid is mixed with substances that contain terminal OH groups, such as cellulose, the sulfuric acid can extract water from the cellulose. The cellulose can turn black, in a process also called carbonization or charring. In the course of this, the cellulose is also decomposed.

[0050] If different ratios of concentrated sulfuric acid are mixed with methanesulfonic acid, both a stronger or faster carbonization and a faster decomposition of the cellulose are generally expected with increasing sulfuric acid content.

[0051] The exemplary compositions are summarized in the following Tables 1 and 2. In the experiment, a total amount of composition of 125 g was used (i.e. 100% correspond to 125 g cleaning composition in the experiment): Table 1:componentCompositionin %ABCDFDDMSA10095908583.280H 2 SO 4 5101514.920excipients1.9 Table 2: componentCompositionin %EEEHIKGMSA70605040200H 2 SO 4 3040506080100excipients

[0052] The sulfuric acid used in the experiments was concentrated sulfuric acid (96%; CAS 7664-93-9). The MSA used in the experiments was 99% MSA (CAS 75-75-2). The excipients used in composition F were composed of 2,2',2"-nitrilotrisethanol 6-[(3,5,5-trimethyl-1-oxohexyl)amino]hexanoate salt (1.0% of a 50% compound), a mixture of benzyl C12-C14 alkyl dimethylammonium chloride and benzyl C12-C16 alkyl dimethylammonium chloride (0.48% of a 50% compound), and C12 / C18 alkyl dimethyl amine oxide (0.30% of a 30% compound).

[0053] To test this, a sanitary tampon (Tpn) is placed in a test tube and mixed with 10g of each of the acid mixtures, and the decomposition or charring (discoloration) of the tampon is observed.

[0054] For better visualization, photos were taken after 3, 7, 10 and 14 minutes (see Figure 1; compositions A, B, C, F, D, DD, E, EE, H, I, K, G from left to right). Already after 3 minutes a distinct black discoloration can be seen from compositions DD to G (H 2 SO 4 content at 20% -100%). In contrast to this A (0% H 2 SO 4 , 100% MSA) showed no discoloration after 3 minutes.

[0055] Figure 1 shows the results of the experiments on the charring and decomposition strength of various sulfuric acid-methanesulfonic acid Mixtures. Recordings after 3 min (Fig. 1a), 7 min (Fig. 1b), 10 min (Fig. 1c) and 14 min (Fig. 1d). The following charring rates can therefore be established for the following mixtures can be determined: G = K > I = H = EE > E ≫ DD > D > F > C > B > A

[0056] In order to evaluate the decomposition strength of the acids, the experiment was stopped after 15 minutes and the pads were removed from the test tube. Figure 2 shows the pads after being affected by the solutions having different H 2 SO 4 / MSA concentrations.

[0057] Figure 2 (light grey line) shows an increase in the decomposition from 0% H 2 SO 4 (and thus 100% MSA) to 10% H 2 SO 4 . In the range between 10 - 20% of sulfuric acid content, the graph forms a plateau. That is, the complete decomposition of the inside of the pad has been achieved, thus showing the improved dissolution properties of the mixtures. Subsequently, the decomposition strength decreases slightly with increasing sulfuric acid content. Especially "G", i.e. 100% Concentrated sulfuric acid surprisingly shows a relatively low decomposition.

[0058] Without wishing to be bound by theory, it can be determined that if rapid initial carbonization takes place, this impairs the distribution of the acid. Without wishing to be bound by theory, the rapid carbonization is assumed to possibly cause a "blockage" inside the tampon. This could "block" the absorption of further acid into the carbon formed by the initial acid interaction, so that any subsequent dissolution of the tampon proceeds more slowly and the tampons decompose more slowly, whereas compositions as defined in the claims provide a surprising high dissolution of the sanitary tampon, thus showing the improved dissolving and cleaning properties.Example 2 - Hygroscopic properties of acids and acid mixtures

[0059] In the experiments of Example 2, the hygroscopic properties of various compositions comprising sulfuric acid and / or methanesulfonic acid were assessed. As discussed above, sulfuric acid is known for its hydrophilic / hygroscopic properties.

[0060] Acids containing sulfur oxide are known for their dehydrating effect. The water molecules can be drawn not only from organic substances such as cellulose, but also from the air. In order to determine the influence of the concentration ratios of sulfuric acid with methanesulfonic acid on the strength of the hygroscopic effect, the different acid solutions were left to stand for 48 hours (2d) in an open beaker under standard beaker under standard conditions (room temperature (25 °C, 1 atm).

[0061] The same experiments were then carried out on the 2d-old solutions as on freshly prepared solutions. If a solution is left open, several effects can take place simultaneously. First, liquids evaporate, the rate depending on several factors such as ambient pressure, ambient temperature or the specific vapor pressure. Since MSA and sulfuric acid have a similar specific vapor pressure, and since all solutions are subject to the same ambient conditions, the effect of evaporation can be neglected. In addition to evaporation, solutions with the appropriate properties can also react with the gas molecules in the air, for example with water.

[0062] Due to its molecular structure, sulfuric acid is expected to have a stronger dehydrating effect compared to methanesulfonic acid. As already mentioned, in the reaction of concentrated acid solutions with water, an exothermic protolysis takes place, whereby the temperature rises abruptly. Investigation of dilute solutions with water showed that the higher the proportion of water in the acid solutions, the lower the maximum temperature T Max during protolysis in water. Differences in the protolysis (resulting from the components) and / or the specific components can also affect the dissolution of sanitary tampons as summarized in the following Table 3 which shows the results of a hydrolysis and dissolution experiment: Table 3: Overview of the measured T Max measured after protolysis of the various acids / acid solutions with water. The column (Dissolution of sanitary tampon) shows the effect of the sample on a sanitary tampon.SampleH 2 O [w%]MSA [w%]H 2 SO 4 [w%]T Max [°C]Dissolution of sanitary tamponD0851590.995% dissolvedW-A5801571.550% dissolvedW-B10751562.6slight changes / dissolution of the materialW-C15701553.5slight changes / dissolution of the materialH 2 O1000023no change / dissolution of the material

[0063] Therefore, lower T Max is expected for the 2d-old solutions during protolysis. In fact, lower T Max were obtained for all acid solutions. Looking at the measured T Max values with the increase in sulfuric acid concentration, no linear dependence of T Max on w% H 2 SO 4 is observed for the 2d-aged solutions compared to the freshly prepared solution, as shown in Table 4. Instead, two strongly linear trends for the range of 10 - 20% and 40 - 80% H 2 SO 4 . 40 - 80% H 2 SO 4 can be observed. In addition, the pure concentrates, solution A (100% MSA) and solution G (100% H 2 SO 4 ), deviate significantly from both linear trends.

[0064] To gain a better understanding of the change caused by leaving the solution open, the difference dT Max of the fresh solution is compared with the T Max of the 2d-old solution: dT Max w% = T Max , fresh w % − T Max , 2d w%

[0065] Since sulphuric acid can attract water more strongly than methanesulphonic acid, a higher dT Max is expected with increasing w% H 2 SO 4 .

[0066] A dT Max difference of 14.1 °C is obtained for the pure concentrate 100% MSA (solution A) and a dT Max difference of 20.8 °C for the pure concentrate 100% H 2 SO 4 (solution G). This initially corresponds to expectations, whereby dT Max 100% H 2 SO 4 is > dT Max 100% MSA.

[0067] However, if the MSA / H 2 SO 4 mixtures are considered, a clear deviation from the expected values can be observed. For example, the range from 10 - 80% H 2 SO 4 behaves constantly at an average temperature of dT Max (10 -80%) = 6.5 +-1.8 °C (wherein the '+-' average dT Max of 10-80% is defined by the standard deviation of 1 sigma). This means that independent of the MSA / H 2 SO 4 mixing ratio for the 10 - 80% range, the dT Max values do not change. This is very unexpected as dT Max should increase with increasing w% H 2 SO 4 (see Figure 3). Therefore, a linear dependence of the w% H 2 SO 4 is expected with the formula dT Max (w%H 2 SO 4 ) = 7*w% + 14°C (see expected dT Max (fresh-2d) values in Table 4. The MSA / H 2 SO 4 - mixtures appear to have less of a dehydrating effect than the pure concentrates in the mixture. Apparently, the acids interact with each other in such a way that they take up less water than in the concentrate.

[0068] Table 4 compares the expected dT Max values with the actual values. If the acid solutions are left to stand in the open beaker for 48 hours and the maximum temperatures of the solutions are then measured during protolysis, clear differences between the various concentration ranges can be observed. For example, the T Max for the 10 - 20% H 2 SO 4 range increases faster compared to the 40 - 80% H 2 SO 4 range, with increasing w% H 2 SO 4 . In addition, the T Max values for the 2d-old solutions for the MSA / H 2 SO 4 mixtures generally differ significantly from the pure concentrates. Table 4: Overview of the measured T Max measured during protolysis of the various acid solutions with water (1:1), a freshly prepared solution and a 2d-old solution. The column (dT Max (2d-fresh)) shows the difference between the T Max of the fresh solution minus the 2d-old solution.Comp.wt% MSA (conc.)w% H 2 SO 4 (conc.)T Max , fresh [°C]T Max , 2d [°C]dT Max (fresh-2d) observed [°C]dT Max (fresh-2d) expectation [°C]Δ (dTMax (fresh-2d) expectation vs. observed [°C]A100087.973.914.114.00.1C901089.783.06.714.7-8.0F83.214.987.081.35.715.0-9.3D851590.984.26.715.1-8.4DD802089.586.72.815.4-12.6EE604094.485.19.316.8-7.5I406096.989.77.118.2-11.1K2080100.292.87.419.6-12.2G0100104.984.120.821.0-0.2

[0069] If the differences in the dT Max for the fresh and 2d-old solutions are drawn, the special feature of the MSA / H 2 SO 4 mixtures compared to the pure concentrates can be recognized more clearly. The dT Max values behave independently of the sulphuric acid concentration for the 10-80% range.

[0070] These results are remarkable, since for increasing w% H 2 SO 4 should be accompanied by a greater temperature loss, as sulphuric acid can extract more water from the air from the air and the dT Max should shrink due to the higher water content. This could be observed very well for the 100% H 2 SO 4 mixture. The fact that the dT Max values of the MSA / H 2 SO 4 mixtures are even lower than those of 0% H 2 SO 4 (100% MSA) is all the more surprising. Without wishing to be bound by theory, an interaction of the MSA / H 2 SO 4 molecules could develop a special interaction with each other, resulting in the improved dissolution properties as well as the surprising influence of the temperature profile of the acid mixtures.

[0071] The pipe cleaning compositions of the present invention thus provide surprising advantages in the charring and dissolution properties in comparison to compositions of the prior art.

Examples

example 1 -

Example 1 - Charring / carbonization and dissolution of sanitary tampons

[0049]In the experiments of Example 1, the dissolution properties of various compositions comprising sulfuric acid and / or methanesulfonic acid regarding cellulose-based materials was assessed. As discussed above, sulfuric acid is known for its hydrophilic properties. When sulfuric acid is mixed with substances that contain terminal OH groups, such as cellulose, the sulfuric acid can extract water from the cellulose. The cellulose can turn black, in a process also called carbonization or charring. In the course of this, the cellulose is also decomposed.

[0050]If different ratios of concentrated sulfuric acid are mixed with methanesulfonic acid, both a stronger or faster carbonization and a faster decomposition of the cellulose are generally expected with increasing sulfuric acid content.

[0051]The exemplary compositions are summarized in the following Tables 1 and 2. In the experiment, a total amount of composition ...

[0001] The present invention relates to pipe cleaning compositions comprising sulfuric acid, a sulfonic acid and wherein the composition comprises low amounts of water as defined in the claims. The invention further relates to methods of cleaning a pipe, the method involving the addition of the composition as defined in the claims, as well as the use of the compositions in methods of cleaning a pipe as defined in the claims.Technical background

[0002] Pipes, drains and traps in the kitchen or bath can often be blocked or slowed by buildup of organic and / or inorganic matter, such as grease, soap, hair, or food waste in combination with e.g. cellulosic materials. Such organic blockage or partial blockage can be cleared mechanically or chemically with a variety of different trap and drain cleaners including concentrated acids or alkalis, oxidizing agents, and foaming or non-foaming combinations of these cleaners or biological systems.

[0003] Pipe cleaning compositions are specialized chemical solutions formulated to remove obstructions and clean the internal surfaces of pipes. These compositions are essential in preventing and addressing clogs, thereby ensuring the smooth operation of plumbing systems in residential, commercial, and industrial environments. Among various types of pipe cleaners, acid-based formulations are particularly effective in breaking down organic and inorganic materials.

[0004] Acid-based pipe cleaning compositions primarily utilize strong acids to dissolve blockages. These compositions are highly effective against a wide range of clogs, including those caused by hair, soap scum, grease, and mineral deposits. The acids commonly used in these cleaners include hydrochloric acid, sulfuric acid, and phosphoric acid. Each of these acids offers unique properties that make them suitable for different types of pipe cleaning applications.

[0005] Sulfuric acid (H 2 SO 4 ) is a prominent ingredient in many high-strength pipe cleaning formulations due to its potent chemical properties. It is a highly corrosive, dense, oily liquid that can effectively break down organic materials such as hair, grease, and paper products. The mechanism by which sulfuric acid cleans pipes involves several key reactions: 1. Hydrolysis: Sulfuric acid reacts highly exothermic with water to produce hydronium ions (H 3 O +< ) and bisulfate ions (HSO 4 -< ), which are highly reactive. 2. Oxidation: The acid acts as an oxidizing agent, breaking down complex organic molecules into simpler compounds, which are then easier to wash away. 3. Dehydration: Sulfuric acid has a strong affinity for water, and it can dehydrate organic materials, effectively reducing them to carbon and water vapor.

[0006] The efficacy of sulfuric acid in pipe cleaners is enhanced by its ability to generate heat upon contact with water, which can help to melt fats and other semi-solid blockages.

[0007] While sulfuric acid-based pipe cleaners are highly effective, they must be used with caution. The corrosive nature of sulfuric acid poses significant safety risks, including chemical burns and respiratory hazards. Proper personal protective equipment (PPE), such as gloves and goggles, should be worn when handling these products. Additionally, these cleaners should be used in well-ventilated areas to avoid inhalation of fumes.

[0008] Sulfuric acid-based pipe cleaning compositions are a powerful solution for clearing severe blockages in plumbing systems. However, their ability to rapidly dissolve organic materials and generate heat can hamper dissolution of clogging materials which is required for residue-free dissolution and the full restoration of the functionality of pipes.

[0009] DE 100 36 607 A1 discloses the use of acid preparations for cleaning and / or disinfecting hard surfaces, as well as a method for cleaning and disinfecting installations, further to corresponding acid cleaning and / or disinfecting agents containing, in relation to the whole agent, a) 1 to 95 w% of at least one acid chosen from phosphoric acid, alkanesulfonic acid, nitric acid and sulphuric acid, and b) 1 to 40 w% of un-decylenic acid, the remainder which completes the 100 w% being water and / or other auxiliary agents and / or active ingredients. US 8,188,025 B2 discloses acidic sanitizing and / or cleaning compositions comprising a specific quaternary antimicrobial system consisting of C1-C4 hydroxyalkyl carboxylic acids, C5-C18 alkyl monocarboxylic acids, unsubstituted or substituted, saturated or unsaturated C4-dicarboxylic acids and additional inorganic or organic acids. EP 3 228 688 B1 discloses liquid acidic hard surface cleaning composition comprising certain copolymers that provide good limescale removal and long lasting shine to a broad range of surfaces, furthermore, when formulated with suitable acid systems, they also provide improved surface safety over more delicate surfaces. WO 2017 / 007416 A1 discloses acid detergent compositions, concentrates and use solutions prepared from the concentrates and methods of using the same, wherein the acid detergent compositions are particularly suited for use in removing soils, especially milk soils, from clean-in-place systems, such as those commonly used in the dairy and food processing industries, wherein the detergent compositions comprise an acidic component including an inorganic or alkanesulfonic acid and a blend of surfactants to provide high cleaning efficiency and low foam generation, wherein the acid detergent compositions optionally comprise an antimicrobial agent to impart a sanitization functionality to the detergent.Summary of the invention

[0010] The inventors have realized the need for an improved pipe cleaning composition, wherein, in particular, the dissolving capacity is increased, in particular towards cellulose-based components, and the dissolving properties of the compositions can be fully utilized.

[0011] In one aspect according to the present disclosure, there is provided a pipe cleaning composition comprising: sulfuric acid in an amount of from 5 to 30% by weight of the composition, a sulfonic acid in an amount of from 40 to 95% by weight of the composition, wherein the amount of total water in the composition is less than 20% by weight of the composition.

[0012] In a further aspect according to the present disclosure there is provided a method of cleaning a pipe, the method comprising: a) adding a pipe cleaning composition comprising sulfuric acid in an amount of from 5 to 30% by weight of the composition and sulfonic acid in an amount of from 40 to 95% by weight of the composition into a pipe, and b) flushing the pipe with a liquid, preferably water, after adding the cleaning composition.

[0013] In a further aspect according to the present disclosure there is provided the use of a composition as defined in the claims in a method of cleaning and / or unclogging a soiled and / or clogged pipe, preferably for use in a method cleaning and / or unclogging a clogged pipe, wherein the pipe is soiled and / or clogged essentially by a cellulose-comprising material.Brief description of the drawings

[0014] Figure 1 shows the effect of sulfuric acid, methanesulfonic acid and mixtures thereof in varying ratios on sanitary tampons at different reaction times. Figure 2 shows the degree of charring (dark grey) and the degree of dissolution (light grey) of sanitary tampons by sulfuric acid, methanesulfonic acid and mixtures thereof. Figure 3 shows the observed temperature profile from the dissolution / addition of various MSA / H 2 SO 4 mixtures to / with water as compared with expected values. Detailed description of the invention

[0015] Surprisingly, the present inventors found that pipe cleaning compositions comprising: sulfuric acid in an amount of from 5 to 30% by weight of the composition, a sulfonic acid in an amount of from 40 to 95% by weight of the composition, and wherein the amount of total water in the composition is less than 20% by weight of the composition as defined in the claims provide dissolving and thus cleaning properties which are significantly enhanced. Examples 1 and 2 show the physical and chemical properties of the compositions of the present invention when used for pipe cleaning applications, exemplified, in particular, by the dissolution of cellulose-based components. Cellulose-based materials that can soil and / or clog pipes (e.g. in households) include but are not limited to sanitary pads, sanitary napkins, sanitary tampons etc.

[0016] The term "pipe cleaning composition" as used herein refers to any formulated composition, mixture, product, or solution designed to maintain, restore, or enhance the functionality of plumbing systems by removing obstructions, dissolving build-ups, and preventing future blockages within pipes. These compositions achieve their purpose through various mechanisms, including chemical reactions, biological processes, or mechanical actions, tailored to address specific types of clogs and pipe materials. In principle, the term refers to cleaning compositions which are particularly suitable for cleaning applications in pipes and / or pipe systems, such as the opening of (clogged and / or soiled) drains, wherein the pipes can be of various inorganic, organic or mixtures of inorganic and organic materials, including, metal, glass, ceramic, plastic, polymeric material, composites etc.

[0017] The pipe cleaning compositions comprise sulfuric acid in an amount effective to provide the desired cleaning properties. Sulfuric acid can be present in an amount of from 5 to 30% by weight of the composition. Sulfuric acid can be present in an amount of from 7.5 to 20% by weight of the composition, preferably from 10 to 17% by weight of the composition, further preferably in an amount of from 12 to 15% by weight of the composition. Sulfuric acid can be present in an amount of about 14 to 15% by weight of the composition, such as 14.2 to 14.8%, 14.3 to 14.7%, 14.4 to 14.6%, most preferably about 14.4% by weight of the composition. The weight% of sulfuric acid as referred to herein and as defined in the claims refer to the amount or concentration of pure sulfuric acid, that is, without water (i.e. non-aqueous). That is, in order to provide a compositions comprising 14.4 weight% sulfuric acid, 15.0 weight% of a 96% sulfuric acid solution can be used.

[0018] A compositions comprising sulfuric acid in a concentration as above can provide excellent dissolution properties, in particular with respect to cellulose-based materials, without yielding excessive and / or potentially dangerous temperature peaks or resulting in carbonization or charring or clogging materials.

[0019] Sulfuric acid can be added as a solution of pure sulfuric acid in water, for example as a solution of 99%, 98%, 97% or 96% pure sulfuric acid in water (i.e. "concentrated sulfuric acid"). Sulfuric acid may contain not only H 2 SO 4 molecules, but can actually be an equilibrium of many other chemical species, as exemplified in the following: HSO 4 -< (15.0 mMol / kg), H 3 SO 4 +< (11.3 mMol / kg), H 3 O +< (8.0 mMol / kg), HS 2 O 7 (4.4 mMol / kg), H 2 S 2 O 7 (3.6 mMol / kg), H 2 O (0.1 mMol / kg). As noted above, in order to provide a compositions comprising 14.4 weight% sulfuric acid, 15.0 weight% of a 96% sulfuric acid solution is added. Similarly, in order to provide a compositions comprising 14.7 weight% sulfuric acid, 15.0 weight% of a 98% sulfuric acid solution can be used.

[0020] The pipe cleaning compositions also comprise a sulfonic acid in an amount effective to provide the desired cleaning properties. The sulfonic acid can be present in an amount of from 40 to 95% by weight of the composition. The sulfonic acid can be present in an amount of from 50 to 90% by weight of the composition, preferably from 65 to 87.5% by weight of the composition, further preferably in an amount of from 80 to 85% by weight of the composition. Sulfonic acid can be present in an amount of about 82 to 83%, about 82.2 to 82.8%, about 82.3 to 82.5%, most preferably in an amount of about 82.4% by weight of the composition.

[0021] A compositions comprising sulfonic acid in a concentration as above in combination with sulfonic acid can provide excellent dissolution properties, in particular with respect to cellulose-based materials, without yielding excessive and / or potentially dangerous temperature peaks or resulting in carbonization or charring or clogging materials.

[0022] The term "sulfonic acid" as used herein refers to a member of the class of organosulfur compounds with the general formula R-S(=O) 2 -OH, where R is an organic alkyl group or aryl group and the S(=O) 2 (OH) group a sulfonyl hydroxide. The alkyl group can be linear or branched. The alkyl group can be substituted or unsubstituted. The alkyl group can comprise from 1 to 8 carbon atoms, preferred are 1 to 6 carbon atoms, further preferred from 1 to 3 carbon atoms, further preferably one carbon atoms (methanesulfonic acid). The aryl group can be saturated or unsaturated. The aryl group can be substituted or unsubstituted. The aryl group can comprise from 5 to 8 carbon atoms, preferred are 5 to 6 carbon atoms, further preferably 6 or 7 carbon atoms (p-toluenesulfonic acid or benzenesulfonic acid). As a substituent, it is also known as a sulfo group. A sulfonic acid can be described also as sulfuric acid with one hydroxyl group replaced by an organic substituent. The parent compound (with the organic substituent replaced by hydrogen) is the parent sulfonic acid, HS(=O) 2 (OH), a tautomer of sulfurous acid, S(=O)(OH) 2 . The term "about" as used herein refers to all values within + / - 10% of the respective value, that is, the expression 'about 1' refers to all values of from 0.9 to 1.0, preferably to all values within + / - 5% of the respective value, that is, the expression 'about 1' refers preferably to all values of from 0.95 to 1.05, further preferably to all values within + / - 1% of the respective value, that is, the expression 'about 1' refers to all values of from 0.99 to 1.01.

[0023] The sulfonic acid can comprise one or more selected from the group consisting of methanesulfonic acid (MSA), ethanesulfonic acid (ESA), benzenesulfonic acid (BSA), p-toluenesulfonic acid (p-TSA), camphorsulfonic acid (CSA), naphthalenesulfonic acid (NSA), dodecylbenzenesulfonic acid (DBSA), 2-naphthalenesulfonic acid (2-NSA), styrenesulfonic acid (SSA), 4-aminobenzenesulfonic acid (4-ABS), preferably one or more selected from the group consisting of methanesulfonic acid (MSA) ethanesulfonic acid (ESA), benzenesulfonic acid (BSA), and p-toluenesulfonic acid (p-TSA), further preferably the sulfonic acid comprises methanesulfonic acid (CH 4 O 3 S).

[0024] The sulfonic acid can comprise at least 70% by weight of methanesulfonic acid based on the amount of sulfonic acid, wherein the remaining amount of sulfonic acid is selected from the group of water, further sulfonic acids, stabilizers, further additives or combinations thereof. The sulfonic acid can comprise at least 80% by weight of methanesulfonic acid based on the amount of sulfonic acid at least 85% by weight of methanesulfonic acid based on the amount of sulfonic acid at least 90% by weight of methanesulfonic acid based on the amount of sulfonic acid at least 95% by weight of methanesulfonic acid based on the amount of sulfonic acid. In some embodiments the sulfonic acid is methanesulfonic acid. As discussed for the sulfuric acid, the weight% of the sulfonic acid (e.g. methanesulfonic acid) as referred to herein and as defined in the claims refer to the amount or concentration of pure sulfonic acid (e.g. methanesulfonic acid), that is, without water (i.e. non-aqueous). That is, in order to provide a compositions comprising 82.4 weight% methanesulfonic acid, 83.2 weight% of a 99.5% methanesulfonic acid solution can be used (e.g. Lutropur MSA 100 ®< by BTC Europe GmbH).

[0025] The total amount of water in the composition is less than 20% by weight of the composition. The total amount of water in the composition can be less than 20%, less than 15%, less than 10%, less than 7.5%, less than 5%, or less than 2.5% by weight of the composition. In some embodiments, the total amount of water in the composition is about 2.4% by weight of the composition or less such as 2% by weight or less, 1.5% by weight or less etc.

[0026] A compositions comprising concentrations of water as above can provide excellent dissolution properties, in particular with respect to cellulose-based materials while providing also a controlled temperature increase while applied to clean and / or unclog drains or pipes wherein water molecules are present which result in an exothermic protonation.

[0027] The composition can further comprise a corrosion inhibitor, preferably an organic corrosion inhibitor, further preferably an organic corrosion inhibitor selected from the group consisting of substituted or unsubstituted alcohol amines or salts thereof, further preferably the composition further comprises the corrosion inhibitor 2,2',2"-nitrilotrisethanol 6-[(3,5,5-trimethyl-1-oxohexyl)amino]hexanoate salt. In some embodiments, the corrosion inhibitor in the composition is 2,2',2"-nitrilotrisethanol 6-[(3,5,5-trimethyl-1-oxohexyl)amino]hexanoate salt (e.g. CAS 242482-67-3).

[0028] The corrosion inhibitor can be present in an amount of from 0.1 to 2.0% by weight of the composition, preferably in an amount of from 0.2 to 1.0% by weight of the composition, further preferably in an amount of from 0.4 to 0.6% by weight of the composition. Most preferably, the corrosion inhibitor is 2,2',2"-nitrilotrisethanol 6-[(3,5,5-trimethyl-1-oxohexyl)amino]hexanoate salt and present in an amount of about 0.5% by weight of the composition.

[0029] The addition of corrosion inhibitors as above can provide excellent corrosion protection of steel, a reduction of copper and cobalt leaching, low foaming, the corrosion inhibitors can be hard-water stable, can be boron free etc. The addition of such corrosion inhibitors can provide compositions which are highly effective in the dissolution of specific organic compounds (such as cellulose from sanitary pads, sanitary napkins, sanitary tampons etc.), while corrosion of the pipes or drains to be cleaned is avoided.

[0030] The composition can further comprise a cationic, anionic, amphoteric or neutral surfactant, preferably a cationic surfactant, further preferably a quaternary ammonium surfactant, further preferably an alkyldimethylbenzylammonium chloride surfactant, further preferably the composition comprises, preferably consists of, the cationic surfactant benzyl C12-C14 alkyl dimethylammonium chloride, benzyl C12-C16 alkyl dimethylammonium chloride (e.g. CAS 68424-85-1), or combinations thereof.

[0031] The cationic surfactant can be present in an amount of from 0.05 to 1.0% by weight of the composition, preferably in an amount of from 0.1 to 0.5% by weight of the composition, further preferably in an amount of from 0.2 to 0.3% by weight of the composition. In some embodiments, the cationic surfactant is a combination of benzyl C12-C14 alkyl dimethylammonium chloride and benzyl C12-C16 alkyl dimethylammonium chloride and is present in an amount of about 0.24% by weight of the composition.

[0032] The addition of cationic surfactants as above can provide excellent interfacial interaction, thereby allowing penetration of solutions (e.g. water) in materials with generally low water affinity. That is, the addition of such surfactants can provide compositions which are highly effective against and effectively penetrate specific organic compounds (such as cellulose) when these are not highly water-affine and / or contaminated with hydrophobic compounds, such as oils, grease etc.

[0033] The composition can be free from enzymes, ionic liquids, sodium hydroxide, potassium hydroxide, oxidizing agents such as peroxides and chloroxides, ammonia and / or organic solvents. That is, in some embodiments, the composition is free of other components which can be used in (pipe) cleaning composition that might possibly be detrimental from an ecological or an applicability point of view. That is, in some embodiments, the cleaning properties are essentially provided by the combination of sulfuric acid and sulfonic acid. By omitting compounds which are employed in pipe cleaning compositions of the prior art, the present invention allows for a simplified and highly efficient pipe cleaning composition, wherein no side-reaction with potentially detrimental components can occur.

[0034] The pipe cleaning composition can comprise, preferably consist of: a) methanesulfonic acid in an amount of from 82 to 84% by weight of the composition, optionally 82.4% by weight of the composition, b) sulfuric acid in an amount of from 13 to 15% by weight of the composition, optionally 14.4% by weight of the composition c) 2,2',2"-nitrilotrisethanol 6-[(3,5,5-trimethyl-1-oxohexyl)amino]hexanoate salt in an amount of from 0.25 to 1.0% by weight of the composition, optionally 0.5% by weight of the composition d) a mixture of benzyl C12-C14 alkyl dimethylammonium chloride and benzyl C12-C16 alkyl dimethylammonium chloride in an amount of from 0.1 to 1.0% by weight of the composition, optionally 0.24% by weight of the composition e) C12 / C18 alkyl dimethyl amine oxide in an amount of from 0.05 to 0.5% by weight of the composition, optionally 0.09% by weight of the composition; and f) water, preferably in an amount of from 0.5 to 5% by weight of the composition, further preferably in an amount of about 2.4% by weight of the composition.

[0035] In further embodiments, the present invention refers to a method of cleaning a pipe, the method comprising: a) adding a pipe cleaning composition comprising sulfuric acid in an amount of from 5 to 30% by weight of the composition and sulfonic acid in an amount of from 40 to 95% by weight of the composition into a pipe, and b) flushing the pipe with a liquid, preferably water, after adding the cleaning composition.

[0036] As discussed above, the pipes to be cleaned can be of various inorganic, organic or mixtures of inorganic and organic materials, including, metal, glass, ceramic, plastic, polymeric material, composites etc. but are not limited to the same. The step of adding the composition can be performed in one shot or continuously over a certain time frame. The step of adding the composition can be performed by simply pouring the composition into the pipe to be cleaned or can be added with a device, such as injection pumps, pressure washers, drain snakes with release compartments etc., into the material clogging or soiling the pipe.

[0037] After adding the cleaning composition, the pipe can eventually be flushed with a liquid. The flushing step is, however, not essential to the cleaning properties of the composition, i.e. is not essential to carrying out the invention which relates to cleaning and / or unclogging the pipe. The step of flushing the pipe after adding the cleaning composition can also be performed during regular use of the pipe. Flushing the pipe can, however, be necessary in order to remove remaining cleaning composition and or material from the pipe prior to resuming the regular function of the pipe. Flushing the pipe is performed with a liquid in order to remove all remaining components from the cleaning composition or the material which was removed by the cleaning composition. The liquid can depend on the material of the pipe, on the functionality of the pipe etc. In household applications of the cleaning composition, water is preferably used for the flushing step, in particular for environmental reasons.

[0038] The flushing step can be performed within a certain timeframe after adding the cleaning composition. The timeframe generally depends on the specific components and concentrations of the cleaning composition, as well as the pipe (material, volume etc.) and the material (type, density, drying state etc.) which has to be removed by the cleaning compositions. Generally, the flushing can, for example, be performed at any point after adding the cleaning composition but is preferably performed after about 24 hours or less, after about 12 hours or less, after about 8 hours or less, after about 6 hours or less, after about 4 hours or less, after about 2 hours or less, after about 1 hour or less, after about 30 minutes or less.

[0039] In some embodiments, the method further comprises agitating the pipe cleaning composition in the pipe, preferably by using a plunger or by mechanically stirring the cleaning composition. Agitating the composition in the pipe can used to increase the cleaning and / or unclogging effect of the method but is not essential to carrying out the invention. That is, agitating the composition can increase the interfacial interaction of the oxonium ions (H 3 O +< ) that are present when the cleaning composition reacts with water molecules, with the material that soils and / or clogs the pipe. Furthermore, mechanically agitating further introduces additional instability into a material clogging a pipe and can therefore increase the cleaning effect.

[0040] In preferred embodiments, a composition as described above is used in the method of cleaning a pipe. That is, in most preferred embodiments, a cleaning composition comprising, preferably consisting of: a) methanesulfonic acid in an amount of from 82 to 84% by weight of the composition, b) sulfuric acid in an amount of from 13 to 15% by weight of the composition, c) 2,2',2"-nitrilotrisethanol 6-[(3,5,5-trimethyl-1-oxohexyl)amino]hexanoate salt in an amount of from 0.25 to 1.0% by weight of the composition, d) a mixture of benzyl C12-C14 alkyl dimethylammonium chloride and benzyl C12-C16 alkyl dimethylammonium chloride in an amount of from 0.1 to 1.0% by weight of the composition, e) C12 / C18 alkyl dimethyl amine oxide in an amount of from 0.05 to 0.5% by weight of the composition; and f) water is used in the method of cleaning a pipe.

[0041] In further embodiments, the present invention refers to the use of the above compositions and as defined in the claims in a method of cleaning and / or unclogging a soiled and / or clogged pipe, preferably for use in a method cleaning and / or unclogging a clogged pipe, wherein the pipe is soiled and / or clogged essentially by a cellulose-comprising material. In particular cellulose-based material can be a source or trigger of clogged pipes due to its chemical and micro-structure.Figure description

[0042] Figure 1 shows the effect of sulfuric acid, methanesulfonic acid and mixtures thereof in varying ratios on sanitary tampons after 3 minutes (Figure 1a), after 7 minutes (Figure 1b), after 10 minutes (Figure 1c) and after 14 minutes (Figure 1d).

[0043] For the experiments underlying the results shown in Figure 1, a sanitary tampon (Tpn) is placed in a test tube and mixed with 10g of each of the acid mixtures, and the decomposition or charring (discoloration) of the tampon is observed. For better visualization, photos were taken after 3, 7, 10 and 14 minutes. Already after 3 minutes a clear black discoloration can be seen from DD to G (H 2 SO 4 content at 20% -100%). In contrast to this A (0% H 2 SO 4 , 100% MSA; as w%) showed no discoloration after 3 minutes. The following charring rates can therefore be established for the following mixtures can be determined: G = K > I = H = EE > E ≫ DD > D > F > C > B > A .

[0044] The results in Figure 1 thus show that generally, the higher the concentration of the sulfuric acid, the faster and / or more intensive the charring of cellulose-based material proceeds.

[0045] Figure 2 shows the degree of charring (dark grey; with a low degree of charring of about 1 a.u. at 0% H 2 SO 4 as shown by the first measurement point on the left side of the graph) and the degree of overall dissolution (light grey; with a higher degree of dissolution of about 4 a.u. at 0% H 2 SO 4 as shown by the first measurement point on the left side of the graph) of cellulose-based sanitary tampons using sulfuric acid, methanesulfonic acid and mixtures thereof in varying ratios after 15 minutes. A value of '0' on the y-axis is indicating no dissolution of the sanitary tampon, a value of '6' on the y-axis is indicating a complete dissolution of the sanitary tampon.

[0046] Solutions of highly concentrated sulfuric acid (e.g. 40% to 100% sulfuric acid of a 96% sulfuric acid; CAS 7664-93-9) show a high level of charring. When decreasing the concentration of sulfuric acid, starting at about below 40% sulfuric acid, the level of charring decreases and reaches a minimum at below 15% sulfuric acid.

[0047] Furthermore, the overall dissolution shows a distinct maximum at from about 5 to 20% sulfuric acid in the solution. At lower and at higher sulfuric acid concentrations, the overall dissolution is reduced. Sulfuric acid concentrations of about 5% to about 20% when combined with about 95% to about 80% methanesulfonic acid (and minor concentrations of optional further components) thus provide a sweet spot with respect to the overall dissolution of cellulose-based materials.

[0048] Figure 3 shows the temperature resulting from dissolving acid mixtures in water (with a range from 10 - 80% H 2 SO 4 as shown on the x-axis) which behaves constantly at a temperature of dT Max (10 -80%) = 6.5 +-1.8 °C while samples 'A' and 'G' show a higher dT Max . This means that independent of the MSA / H 2 SO 4 mixing ratio for the 10 - 80% range, the dT Max values do not change. This is very unexpected as dT Max should increase with increasing w% H 2 SO 4 . That is, a linear dependence from the w% H 2 SO 4 is expected with the formula dT Max (w%H 2 SO 4 ) = 7*w% + 14°C (see expected dT Max (fresh-2d) values in Table 4). The x-axis shows the weight percentage ('w%' or 'wt%' or '% by weighty' of sulfuric acid in the acid mixture, the y-axis show the difference in maximum temperatures between a freshly mixed solution and a solution left at room temperature (RT) for 48 hours (i.e. dT Max (w%H 2 SO 4 ) = (T Max , fresh (w%) - T Max , 2d (w%)). The measurement points of acid solutions A (H 2 SO 4 content (w%) = 0%) and G (H 2 SO 4 content (w%) = 100%) are specially marked by encircling the measurement points. There is no clear trend for a higher temperature difference depending on the H 2 SO 4 content (w%), contrary to expectations.Examples Example 1 - Charring / carbonization and dissolution of sanitary tampons

[0049] In the experiments of Example 1, the dissolution properties of various compositions comprising sulfuric acid and / or methanesulfonic acid regarding cellulose-based materials was assessed. As discussed above, sulfuric acid is known for its hydrophilic properties. When sulfuric acid is mixed with substances that contain terminal OH groups, such as cellulose, the sulfuric acid can extract water from the cellulose. The cellulose can turn black, in a process also called carbonization or charring. In the course of this, the cellulose is also decomposed.

[0050] If different ratios of concentrated sulfuric acid are mixed with methanesulfonic acid, both a stronger or faster carbonization and a faster decomposition of the cellulose are generally expected with increasing sulfuric acid content.

[0051] The exemplary compositions are summarized in the following Tables 1 and 2. In the experiment, a total amount of composition of 125 g was used (i.e. 100% correspond to 125 g cleaning composition in the experiment): Table 1:componentCompositionin %ABCDFDDMSA10095908583.280H 2 SO 4 5101514.920excipients1.9 Table 2: componentCompositionin %EEEHIKGMSA70605040200H 2 SO 4 3040506080100excipients

[0052] The sulfuric acid used in the experiments was concentrated sulfuric acid (96%; CAS 7664-93-9). The MSA used in the experiments was 99% MSA (CAS 75-75-2). The excipients used in composition F were composed of 2,2',2"-nitrilotrisethanol 6-[(3,5,5-trimethyl-1-oxohexyl)amino]hexanoate salt (1.0% of a 50% compound), a mixture of benzyl C12-C14 alkyl dimethylammonium chloride and benzyl C12-C16 alkyl dimethylammonium chloride (0.48% of a 50% compound), and C12 / C18 alkyl dimethyl amine oxide (0.30% of a 30% compound).

[0053] To test this, a sanitary tampon (Tpn) is placed in a test tube and mixed with 10g of each of the acid mixtures, and the decomposition or charring (discoloration) of the tampon is observed.

[0054] For better visualization, photos were taken after 3, 7, 10 and 14 minutes (see Figure 1; compositions A, B, C, F, D, DD, E, EE, H, I, K, G from left to right). Already after 3 minutes a distinct black discoloration can be seen from compositions DD to G (H 2 SO 4 content at 20% -100%). In contrast to this A (0% H 2 SO 4 , 100% MSA) showed no discoloration after 3 minutes.

[0055] Figure 1 shows the results of the experiments on the charring and decomposition strength of various sulfuric acid-methanesulfonic acid Mixtures. Recordings after 3 min (Fig. 1a), 7 min (Fig. 1b), 10 min (Fig. 1c) and 14 min (Fig. 1d). The following charring rates can therefore be established for the following mixtures can be determined: G = K > I = H = EE > E ≫ DD > D > F > C > B > A

[0056] In order to evaluate the decomposition strength of the acids, the experiment was stopped after 15 minutes and the pads were removed from the test tube. Figure 2 shows the pads after being affected by the solutions having different H 2 SO 4 / MSA concentrations.

[0057] Figure 2 (light grey line) shows an increase in the decomposition from 0% H 2 SO 4 (and thus 100% MSA) to 10% H 2 SO 4 . In the range between 10 - 20% of sulfuric acid content, the graph forms a plateau. That is, the complete decomposition of the inside of the pad has been achieved, thus showing the improved dissolution properties of the mixtures. Subsequently, the decomposition strength decreases slightly with increasing sulfuric acid content. Especially "G", i.e. 100% Concentrated sulfuric acid surprisingly shows a relatively low decomposition.

[0058] Without wishing to be bound by theory, it can be determined that if rapid initial carbonization takes place, this impairs the distribution of the acid. Without wishing to be bound by theory, the rapid carbonization is assumed to possibly cause a "blockage" inside the tampon. This could "block" the absorption of further acid into the carbon formed by the initial acid interaction, so that any subsequent dissolution of the tampon proceeds more slowly and the tampons decompose more slowly, whereas compositions as defined in the claims provide a surprising high dissolution of the sanitary tampon, thus showing the improved dissolving and cleaning properties.Example 2 - Hygroscopic properties of acids and acid mixtures

[0059] In the experiments of Example 2, the hygroscopic properties of various compositions comprising sulfuric acid and / or methanesulfonic acid were assessed. As discussed above, sulfuric acid is known for its hydrophilic / hygroscopic properties.

[0060] Acids containing sulfur oxide are known for their dehydrating effect. The water molecules can be drawn not only from organic substances such as cellulose, but also from the air. In order to determine the influence of the concentration ratios of sulfuric acid with methanesulfonic acid on the strength of the hygroscopic effect, the different acid solutions were left to stand for 48 hours (2d) in an open beaker under standard beaker under standard conditions (room temperature (25 °C, 1 atm).

[0061] The same experiments were then carried out on the 2d-old solutions as on freshly prepared solutions. If a solution is left open, several effects can take place simultaneously. First, liquids evaporate, the rate depending on several factors such as ambient pressure, ambient temperature or the specific vapor pressure. Since MSA and sulfuric acid have a similar specific vapor pressure, and since all solutions are subject to the same ambient conditions, the effect of evaporation can be neglected. In addition to evaporation, solutions with the appropriate properties can also react with the gas molecules in the air, for example with water.

[0062] Due to its molecular structure, sulfuric acid is expected to have a stronger dehydrating effect compared to methanesulfonic acid. As already mentioned, in the reaction of concentrated acid solutions with water, an exothermic protolysis takes place, whereby the temperature rises abruptly. Investigation of dilute solutions with water showed that the higher the proportion of water in the acid solutions, the lower the maximum temperature T Max during protolysis in water. Differences in the protolysis (resulting from the components) and / or the specific components can also affect the dissolution of sanitary tampons as summarized in the following Table 3 which shows the results of a hydrolysis and dissolution experiment: Table 3: Overview of the measured T Max measured after protolysis of the various acids / acid solutions with water. The column (Dissolution of sanitary tampon) shows the effect of the sample on a sanitary tampon.SampleH 2 O [w%]MSA [w%]H 2 SO 4 [w%]T Max [°C]Dissolution of sanitary tamponD0851590.995% dissolvedW-A5801571.550% dissolvedW-B10751562.6slight changes / dissolution of the materialW-C15701553.5slight changes / dissolution of the materialH 2 O1000023no change / dissolution of the material

[0063] Therefore, lower T Max is expected for the 2d-old solutions during protolysis. In fact, lower T Max were obtained for all acid solutions. Looking at the measured T Max values with the increase in sulfuric acid concentration, no linear dependence of T Max on w% H 2 SO 4 is observed for the 2d-aged solutions compared to the freshly prepared solution, as shown in Table 4. Instead, two strongly linear trends for the range of 10 - 20% and 40 - 80% H 2 SO 4 . 40 - 80% H 2 SO 4 can be observed. In addition, the pure concentrates, solution A (100% MSA) and solution G (100% H 2 SO 4 ), deviate significantly from both linear trends.

[0064] To gain a better understanding of the change caused by leaving the solution open, the difference dT Max of the fresh solution is compared with the T Max of the 2d-old solution: dT Max w% = T Max , fresh w % − T Max , 2d w%

[0065] Since sulphuric acid can attract water more strongly than methanesulphonic acid, a higher dT Max is expected with increasing w% H 2 SO 4 .

[0066] A dT Max difference of 14.1 °C is obtained for the pure concentrate 100% MSA (solution A) and a dT Max difference of 20.8 °C for the pure concentrate 100% H 2 SO 4 (solution G). This initially corresponds to expectations, whereby dT Max 100% H 2 SO 4 is > dT Max 100% MSA.

[0067] However, if the MSA / H 2 SO 4 mixtures are considered, a clear deviation from the expected values can be observed. For example, the range from 10 - 80% H 2 SO 4 behaves constantly at an average temperature of dT Max (10 -80%) = 6.5 +-1.8 °C (wherein the '+-' average dT Max of 10-80% is defined by the standard deviation of 1 sigma). This means that independent of the MSA / H 2 SO 4 mixing ratio for the 10 - 80% range, the dT Max values do not change. This is very unexpected as dT Max should increase with increasing w% H 2 SO 4 (see Figure 3). Therefore, a linear dependence of the w% H 2 SO 4 is expected with the formula dT Max (w%H 2 SO 4 ) = 7*w% + 14°C (see expected dT Max (fresh-2d) values in Table 4. The MSA / H 2 SO 4 - mixtures appear to have less of a dehydrating effect than the pure concentrates in the mixture. Apparently, the acids interact with each other in such a way that they take up less water than in the concentrate.

[0068] Table 4 compares the expected dT Max values with the actual values. If the acid solutions are left to stand in the open beaker for 48 hours and the maximum temperatures of the solutions are then measured during protolysis, clear differences between the various concentration ranges can be observed. For example, the T Max for the 10 - 20% H 2 SO 4 range increases faster compared to the 40 - 80% H 2 SO 4 range, with increasing w% H 2 SO 4 . In addition, the T Max values for the 2d-old solutions for the MSA / H 2 SO 4 mixtures generally differ significantly from the pure concentrates. Table 4: Overview of the measured T Max measured during protolysis of the various acid solutions with water (1:1), a freshly prepared solution and a 2d-old solution. The column (dT Max (2d-fresh)) shows the difference between the T Max of the fresh solution minus the 2d-old solution.Comp.wt% MSA (conc.)w% H 2 SO 4 (conc.)T Max , fresh [°C]T Max , 2d [°C]dT Max (fresh-2d) observed [°C]dT Max (fresh-2d) expectation [°C]Δ (dTMax (fresh-2d) expectation vs. observed [°C]A100087.973.914.114.00.1C901089.783.06.714.7-8.0F83.214.987.081.35.715.0-9.3D851590.984.26.715.1-8.4DD802089.586.72.815.4-12.6EE604094.485.19.316.8-7.5I406096.989.77.118.2-11.1K2080100.292.87.419.6-12.2G0100104.984.120.821.0-0.2

[0069] If the differences in the dT Max for the fresh and 2d-old solutions are drawn, the special feature of the MSA / H 2 SO 4 mixtures compared to the pure concentrates can be recognized more clearly. The dT Max values behave independently of the sulphuric acid concentration for the 10-80% range.

[0070] These results are remarkable, since for increasing w% H 2 SO 4 should be accompanied by a greater temperature loss, as sulphuric acid can extract more water from the air from the air and the dT Max should shrink due to the higher water content. This could be observed very well for the 100% H 2 SO 4 mixture. The fact that the dT Max values of the MSA / H 2 SO 4 mixtures are even lower than those of 0% H 2 SO 4 (100% MSA) is all the more surprising. Without wishing to be bound by theory, an interaction of the MSA / H 2 SO 4 molecules could develop a special interaction with each other, resulting in the improved dissolution properties as well as the surprising influence of the temperature profile of the acid mixtures.

[0071] The pipe cleaning compositions of the present invention thus provide surprising advantages in the charring and dissolution properties in comparison to compositions of the prior art.

Examples

example 1 -

Example 1 - Charring / carbonization and dissolution of sanitary tampons

[0049]In the experiments of Example 1, the dissolution properties of various compositions comprising sulfuric acid and / or methanesulfonic acid regarding cellulose-based materials was assessed. As discussed above, sulfuric acid is known for its hydrophilic properties. When sulfuric acid is mixed with substances that contain terminal OH groups, such as cellulose, the sulfuric acid can extract water from the cellulose. The cellulose can turn black, in a process also called carbonization or charring. In the course of this, the cellulose is also decomposed.

[0050]If different ratios of concentrated sulfuric acid are mixed with methanesulfonic acid, both a stronger or faster carbonization and a faster decomposition of the cellulose are generally expected with increasing sulfuric acid content.

[0051]The exemplary compositions are summarized in the following Tables 1 and 2. In the experiment, a total amount of composition ...

Claims

1. Pipe cleaning composition comprising: sulfuric acid in an amount of from 5 to 30% by weight of the composition, a sulfonic acid in an amount of from 40 to 95% by weight of the composition, wherein the amount of total water in the composition is less than 20% by weight of the composition.

2. Pipe cleaning composition according to claim 1, wherein the sulfonic acid comprises methanesulfonic acid.

3. Pipe cleaning composition according to claim 1 or claim 2, wherein the sulfonic acid comprises at least 70% by weight of methanesulfonic acid based on the amount of sulfonic acid.

4. Pipe cleaning composition according to any one of claims 1 to 3, wherein the sulfonic acid is methanesulfonic acid.

5. Pipe cleaning composition according to any one of claims 1 to 4, wherein the sulfonic acid is present in an amount of from 50 to 90% by weight of the composition, preferably from 65 to 87.5% by weight of the composition, further preferably in an amount of from 80 to 85% by weight of the composition.

6. Pipe cleaning composition according to any one of claims 1 to 5, wherein the amount of total water is less than 15% by weight of the composition, further preferably less than 10% by of the composition, further preferably less than 5% by of the composition, further preferably the cleaning composition comprises less than 2.5% by weight of the composition total water.

7. Pipe cleaning composition according to any one of claims 1 to 6, wherein sulfuric acid is present in an amount of from 7.5 to 20% by weight of the composition, preferably from 10 to 17% by weight of the composition, further preferably in an amount of from 12 to 15% by weight of the composition.

8. Pipe cleaning composition according to any one of claims 1 to 7, wherein the composition further comprises a corrosion inhibitor, preferably an organic corrosion inhibitor, further preferably an organic corrosion inhibitor selected from the group consisting of substituted or unsubstituted alcohol amines or salts thereof, further preferably the composition further comprises the corrosion inhibitor 2,2',2"-nitrilotrisethanol 6-[(3,5,5-trimethyl-1-oxohexyl)amino]hexanoate salt.

9. Pipe cleaning composition according to claim 8, wherein the corrosion inhibitor is present in an amount of from 0.1 to 2.0% by weight of the composition, preferably in an amount of from 0.2 to 1.0% by weight of the composition, further preferably in an amount of from 0.4 to 0.6% by weight of the composition.

10. Pipe cleaning composition according to any one of claims 1 to 9, wherein the composition further comprises a cationic surfactant, preferably a quaternary ammonium surfactant, further preferably an alkyldimethylbenzylammonium chloride surfactant, further preferably the composition comprises the cationic surfactant benzyl C12-C14 alkyl dimethylammonium chloride, benzyl C12-C16 alkyl dimethylammonium chloride, or combinations thereof, optionally wherein the cationic surfactant is present in an amount of from 0.05 to 1.0% by weight of the composition, preferably in an amount of from 0.1 to 0.5% by weight of the composition, further preferably in an amount of from 0.2 to 0.3% by weight of the composition.

11. Pipe cleaning composition according to any one of claims 1 to 10, wherein the composition further comprises a neutral surfactant, preferably an amine oxide surfactant, further preferably a cocamidopropyl amine oxide surfactant, further preferably the composition comprises the neutral surfactant C12 / C18 alkyl dimethyl amine oxide, optionally wherein the neutral surfactant is present in an amount of from 0.01 to 1.0% by weight of the composition, preferably in an amount of from 0.05 to 0.5% by weight of the composition, further preferably in an amount of from 0.08 to 0.12% by weight of the composition.

12. Pipe cleaning composition according to any preceding claim comprising, preferably consisting of: a) methanesulfonic acid in an amount of from 82 to 84% by weight of the composition, b) sulfuric acid in an amount of from 13 to 15% by weight of the composition, c) 2,2',2"-nitrilotrisethanol 6-[(3,5,5-trimethyl-1-oxohexyl)amino]hexanoate salt in an amount of from 0.25 to 1.0% by weight of the composition, d) a mixture of benzyl C12-C14 alkyl dimethylammonium chloride and benzyl C12-C16 alkyl dimethylammonium chloride in an amount of from 0.1 to 1.0% by weight of the composition, e) C12 / C18 alkyl dimethyl amine oxide in an amount of from 0.05 to 0.5% by weight of the composition; and f) water.

13. Method of cleaning a pipe, the method comprising: a) adding a pipe cleaning composition comprising sulfuric acid in an amount of from 5 to 30% by weight of the composition and sulfonic acid in an amount of from 40 to 95% by weight of the composition into a pipe, and b) flushing the pipe with a liquid, preferably water, after adding the cleaning composition.

14. Method of cleaning according to claim 13, wherein the method further comprises agitating the pipe cleaning composition in the pipe, preferably by using a plunger or by mechanically stirring the cleaning composition.

15. Use of a composition according to any one of claim 1 to 12 in a method of cleaning and / or unclogging a soiled and / or clogged pipe, preferably for use in a method cleaning and / or unclogging a clogged pipe, wherein the pipe is soiled and / or clogged essentially by a cellulose-comprising material.

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