Deodorizing and sanitizing compositions

Abstract

The present invention relates to a water-soluble deodorizing and sanitizing composition comprising a peroxydisulphate, a surfactant and optionally an acidifying agent or an alkalizing agent. The peroxydisulphate can be a sodium, potassium or ammonium peroxydisulphate. The surfactant can be a non-ionic, anionic or cationic surfactant. The acidifying agent can be citric acid, and the alkalizing agent can be sodium bicarbonate. The composition can be dry mixed or sprayed or nebulized on the material to be treated in the form of a solution, it is able to deodorize and sanitize solid and liquid malodorous matrices of any origin and can also be used in environments and for household surfaces and furnishings. The deodorizing and sanitizing composition is able to selectively reduce only the anaerobic bacterial load. The deodorizing and sanitizing composition can be made in the form of a kit, comprising: sodium, potassium or ammonium peroxydisulphate, a non-ionic, anionic or cationic surfactant, and optionally an acidifying agent or an alkalizing agent.

Description

[0001] DESCRIPTION

[0002] Deodorizing and sanitizing compositions

[0003] The invention concerns water-soluble deodorizing and sanitizing compositions, in particular compositions usable for treating solid or liquid malodorous matrices with a high microbial load, industrial machines and equipment that process municipal solid waste (MSW), surfaces of various nature such as worktops for industrial or domestic food processing.

[0004] PRIOR ART

[0005] Deodorizing solid or liquid malodorous matrices - such as animal or human excretions, municipal solid waste, landfill leachates, industrial wastewater and other malodorous waste - constitutes a significant problem, due to the variety of volatile compounds responsible for unpleasant odors - such as hydrogen sulphide, mercaptans, ammonia, amines, aldehydes and ketones - resulting from the metabolism of microorganisms, mainly anaerobic, which contaminate the aforementioned matrices.

[0006] Most malodorous substances fall into the following categories:

[0007] - volatile compounds of an acidic nature, such as hydrogen sulphide and other sulphur-based compounds, including mercaptans;

[0008] - volatile compounds of an alkaline nature, such as ammonia and amines and more generally compounds originating from decomposition / putrefaction processes;

[0009] - aldehydes and ketones and more generally organic compounds with a more or less unpleasant odour.

[0010] Malodorous matrices generally have a high microbial load and may contain potentially pathogenic microorganisms. It is therefore essential, in addition to eliminating unpleasant odours, to substantially reduce the microbial load of the aforementioned matrices.

[0011] Hopefully, the most suitable compositions for treating malodorous matrices should be able to act as deodorants and sanitizers at the same time, i.e. such compositions should be able to both neutralise unpleasant odours and significantly reduce the bacterial load. European patent no. EP2242518 describes the effectiveness of using deodorizing and sanitizing compositions based on surfactants and peroxymonosulphates, such as the complex salt of peroxymonosulphate (2KHSO5-KHSO4-K2SO4, triple salt containing potassium sulphate and potassium bisulphate) marketed under the name Oxone®, to treat malodorous matrices. The same document EP2242518 also claims that peroxydisulphate, as an alternative to peroxymonosulphate, is less efficient, and therefore less suitable for use as a deodorant and sanitizer.

[0012] In an aqueous environment, peroxymonosulphate generates H2O2 according to the following reaction:

[0013] HSO5- + H2O H2O2 + HSO4-

[0014] The H2O2 / HSO5’ couple has an oxidizing action with a consequent high capacity to attack reducing substrates, such as malodorous substances generated by anaerobic bacteria, and eliminate the latter selectively.

[0015] However, the use of peroxymonosulphate as a deodorant and sanitizer is not without drawbacks.

[0016] One drawback is the toxicity, particularly the acute toxicity, of the compound. In fact, peroxymonosulphate has an acute inhalation toxicity of 50 mg / m3, an acute dermal toxicity of 80 mg / kg body weight and an acute oral toxicity of 10 mg / kg body weight. This constitutes a non-negligible risk to the safety and health of users, both professional and non-professional.

[0017] Another drawback is the impact on the environment due to the use of peroxymonosulphate, since the latter must be stabilized in the form of a triple salt. Therefore, the use of peroxymonosulphate involves the release of significant quantities of sulphates into the environment, in addition to the sulphate released by reduction of peroxymonosulphate as a result of the reaction of the latter with reducing substrates. This can be extremely limiting if a significant amount of peroxymonosulphate needs to be used, for instance to treat large quantities of waste.

[0018] An additional drawback is the production costs, since peroxymonosulphate is produced through a complex and consequently expensive process, namely by reacting oleum (sulphur trioxide dissolved in sulphuric acid) with hydrogen peroxide and then neutralizing it. Furthermore, the aforementioned Oxone® has a markedly acidic pH (pH 2) in aqueous solution and this acidic pH can be aggressive towards some materials. It is therefore necessary to adjust the pH of peroxymonosulphate solutions by adding buffers to them, which further increases production costs.

[0019] A further drawback is the substantial hygroscopicity of peroxymonosulphate. Since the deodorizing and sanitizing compositions based on peroxymonosulphates are solid compositions (powders or granules) that are water-soluble, packaged in water-soluble sachets, it is necessary to add appropriate quantities of anhydrifying compounds to the packages that contain them, which further contributes to increasing production costs.

[0020] Another drawback is the reduced stability of peroxymonosulphate in aqueous solution. In fact, solutions obtained by mixing peroxymonosulphate with water must be replaced after about 15 days from their preparation, since peroxymonosulphate, being characterized by a fast reaction kinetics in water, tends to form mainly H2O2, which is not very stable and consequently, decomposing, causes a decrease in the concentration of the oxidizing active ingredient.

[0021] Therefore, among technicians in the sector there is a strong need to overcome the drawbacks associated with the use of known deodorizing and sanitizing compositions, in particular the deodorizing and sanitizing compositions based on peroxymonosulphates.

[0022] Peroxydisulphate, or persulphate, has been widely studied with particular reference to its activation to eliminate specific toxic substances in aqueous matrices (Aydin Hassani, Jaimy Scaria, Farshid Ghanbari, P.V. Nidheesh. Sulphate radicals- based advanced oxidation processes for the degradation of pharmaceuticals and personal care products: A review on relevant activation mechanisms, performance, and perspectives; Environmental Research, Volume 217, 15 / 01 / 2023, 1 14789) and a significant example is given by the study carried out by Xingyu Li and collaborators (Xingyu Li, Borui Jie, Huidong Lin, Zhongpei Deng, Junyao Qian, Yiqiong Yang, Xiaodong Zhang. Application of sulphate radicals-based advanced oxidation technology in degradation of trace organic contaminants (TrOCs): Recent advances and prospects; Journal of Environmental Management 308 (2022) 1 14664). Two particular applications concern the elimination of the algae Microcystis aeruginosa from aquatic environments, both by activation (Na Gu, Yunxia Wu, Jinlong Gao, Xiaoyu Meng, Pei Zhao, Huihui Qin, Kuitao Wang. Microcystis aeruginosa removal by in situ chemical oxidation using persulphate activated by Fe2+ions; Ecological Engineering 99 (2017) 290-297) and without activation by peroxydisulphate (Zhihao Chen, Jingyi Li, Meiqing Chen, Kok Yuen Koh, Zhongrong Du, Karina Yew-Hoong Gin, Yiliang He, Choon Nam Ong, J. Paul Chen. Microcystis aeruginosa removal by peroxides of hydrogen peroxide, peroxymonosulphate and peroxydisulphate without additional activators; Water Research 201 (2021 ) 1 17263).

[0023] International Application No. WO2022055468 describes the use of mixtures of peroxydisulphate and sodium hydroxide to eliminate viruses, microorganisms, biofilms and fungi in domestic and industrial environments.

[0024] WQ2008040987 describes biocidal formulations, wherein biocide means a substance capable of killing cells, living organisms, such as fungi, spores, bacteria, non-cellular infectious agents containing nucleic acids, such as viruses. The biocidal formulation comprises an iodide or bromide salt, a peroxydisulphate as an oxidizing agent, an acetic acid salt and diluents (which can be surfactants, organic acids and buffering agents). It is specified that the formulation is self-buffering at a pH between 2.5 and 3.5 which increases to pH 4 thanks to the addition of buffering agents. The optimal working pH is pH 3.2. Peroxydisulphate is used as a primary biocide accompanied by the formation of iodine and peroxyacetic acid. The triple action of the formulation is due to the mixture of oxidants, oxyacids and iodophors that together generate free radicals for an optimal attack of DNA and RNA. Peroxydisulphate, thanks to the radical mechanism involved, present in combination with the other ingredients of the formulation, shows a notable destructive power of DNA and RNA, enhancing and expanding the biocidal activity of the formulation itself which is decidedly superior to that of Virkon® with consequent absence of selectivity between aerobic and anaerobic microorganisms, as also demonstrated in the experimental part of this document which also highlights a notable sporicidal activity. It is in fact stated that the thus prepared formulation, exploiting the high oxidation potential of peroxydisulphate (E° 2.01 V), generates in situ both iodine and peracetic acid, which act as additional mechanistic pathways to improve the performance of the biocidal formulation as a whole.

[0025] US2018008524 describes a hair bleaching composition comprising a mixture of two soluble salts of peroxydisulphate, alkalizing agents, surfactants and optionally acids. The surfactants may be anionic, cationic or nonionic.

[0026] US2023126738 describes a method for protecting agricultural and food products from decay. The main ingredient for carrying out the invention is performic acid which is generated in a solution comprising a surfactant, a carboxylic acid, phosphoric acid and an oxidant. KOH or acids may also be added to adjust the pH. The essential ingredient for generating performic acid is the oxidant, preferably hydrogen peroxide. Peroxydisulphate (as sodium, ammonium or potassium salt) is one of the possible oxidants used for the process. Ionic and nonionic surfactants may be added.

[0027] WO209072156 describes a composition that can be in the form of a kit and that includes a persulphate, an alkalizing agent, surfactants that can be of different nature. The preferred form of persulphate is peroxymonosulphate and the composition of three salts is considered to represent the preferred embodiment. The composition can be in the form of a water-soluble deodorizing and sanitizing formulation wherein zeolites are also present. The preferred surfactants are represented by n-alkyl dimethyl ethyl benzyl ammonium chloride or sodium dodecylbenzene sulfonate. Bicarbonate salts are the preferred means to obtain a basic pH. The use is for the treatment of wastewater, for washing household appliances and surfaces.

[0028] As a matter of fact, the compositions of the prior art aim to obtain a decidedly antibacterial, antiviral and disinfectant action without having a particular and specific deodorizing action.

[0029] As generally understood, disinfecting means "destroying all possible microbes of any nature present in an inert object" while the expression "sanitizing" means "making physically clean and substantially reducing in the best and most practical way agents that may be harmful to health".

[0030] Therefore, there was a need to have compositions with an effective deodorizing and sanitizing action that overcome the problems reported above. Unless specifically excluded in the detailed description that follows, what is described in this chapter is to be considered as an integral part of the detailed description of the invention.

[0031] SUMMARY OF THE INVENTION

[0032] An object of the invention is to improve known deodorizing and sanitizing compositions, in particular deodorizing and sanitizing compositions based on peroxymonosulphates.

[0033] Another object is to provide a deodorizing and sanitizing composition that has a lower toxicity than known compositions, so as to significantly reduce any risks to the safety and health of users.

[0034] A further object is to provide a deodorizing and sanitizing composition that is substantially stable in aqueous solution.

[0035] A further object is to provide a deodorizing and sanitizing composition that has a substantially lower environmental impact than that produced by known compositions.

[0036] A further object is to provide a deodorizing and sanitizing composition that is simpler to produce than known compositions and does not require the use of anhydrifying compounds, thereby overall reducing manufacturing costs.

[0037] A further object is to provide a water-soluble container containing a mixture that comprises an aliquot of peroxydisulphate and an aliquot of surfactant such that the mixture in contact with water is capable of generating an oxidizing trio consisting of S2O827H2O2 / O2 and a pH between 4.5 and 1 1 . The container may be a bag, a capsule, a sachet, an envelope or other container made of water-soluble material known to those skilled in the art. The pH that can be used for the composition can preferably be chosen from the following pH ranges: 4.5-5.5; 6.0-7.2; 8.0-9.0; 9.0- 10.5; 10-1 1 ).

[0038] Yet another object is to provide a process for deodorizing and sanitizing materials and / or surfaces and / or environments comprising the steps of:

[0039] • preparing a mixture by mixing together an aliquot of peroxydisulphate and an aliquot of a surfactant; • mixing the resulting mixture with the material to be treated; or alternatively preparing an aqueous solution with said mixture and applying it to the material or surface or dispersing / spraying / nebulizing it in the environment to be treated; said mixture being able to generate an oxidizing trio consisting of S2Os27H2O2 / O2 and a pH between 4.5 and 1 1 when placed in contact with water; said process allowing to deodorize and sanitize materials and / or surfaces and / or environments.

[0040] Yet another object is the use of a composition comprising peroxydisulphate and a surfactant for the sanitization of matrices that in contact with distilled water generates an oxidizing trio consisting of S20s2’ / H2O2 / O2 and a pH between 4.5 and 1 1 .

[0041] Yet another object is the use of a composition comprising peroxydisulphate and a surfactant that in contact with water generates an oxidizing trio consisting of S20s2' / H2O2 / O2 for the selective elimination of anaerobic bacteria present on the surface and inside matrices to be sanitized and deodorized.

[0042] These and other objects will be evident from the detailed description that follows.

[0043] BRIEF DESCRIPTION OF THE FIGURES

[0044] The invention can be better understood and implemented with reference to the attached figures which illustrate an exemplary and non-limiting embodiment of implementation, wherein:

[0045] • Figure 1 : trend of biological oxygen demand (BOD5) in an aqueous medium containing aerobic and anaerobic bacteria (pig manure). BOD5 measures the trend of oxygen absorption by microorganisms in a sample. The measurement of BOD5 was continuously monitored and a graph of its evolution was drawn using the method described in Standard Methods for the Examination of Water and Wastewater APHA-AWWA-WPCF.

[0046] • Figure 2: graph showing a comparison of the trend of the potential dynamic respiration index (PDRI) in a material treated with the composition according to the invention (sample) and in an untreated material (blank).

[0047] • Figure 3: graph showing the trend of the potential dynamic respiration index (PDRI) in an untreated material (blank) with the composition according to the invention.

[0048] • Figure 4: is a graph showing the trend of the potential dynamic respiration index (PDRI) in a treated material (sample) with the composition according to the invention.

[0049] • Figure 5: is a graph showing a comparison of the trend of the potential dynamic respiration index (PDRI), chemical oxygen demand (COD) and total organic carbon (TOC) in a treated material (sample) with the composition according to the invention.

[0050] • Figure 6: continuous flow aerobic respirometer.

[0051] • Figure 7: pilot plant reactor.

[0052] DEFINITIONS

[0053] In the context of the present invention:

[0054] • the terms “peroxydisulphate” and “persulphate” are considered synonymous and can therefore be used interchangeably to identify the anion S2O82";

[0055] • the terms “deodorizing and sanitizing composition according to the invention” and “composition according to the invention” are considered synonymous and can therefore be used interchangeably;

[0056] • the percentages (%) indicated are intended as percentages by weight (i.e., mass on mass, % m / m) with respect to the total composition;

[0057] • the term peroxydisulphate is intended to identify compounds characterized by the presence of the chemical species S2Os27H2O2 / O2 generated when the composition of the invention is placed in contact with distilled water;

[0058] • the terms “about” or “around” as used herein when referring to a measurable value such as a quantity, a time duration, and the like, are intended to encompass variations of ±20%, ±10%, ±5%, ±1 %, or ±0.1 % from the specified value, wherein such variations are appropriate to perform the methods described.

[0059] DETAILED DESCRIPTION OF THE INVENTION

[0060] The invention concerns a water-soluble deodorizing and sanitizing composition based on peroxydisulphate (persulphate) and surfactants, which allows to overcome the drawbacks of known deodorizing and sanitizing compositions and is aimed at replacing in particular the deodorizing and sanitizing compositions based on peroxymonosulphate. Said composition according to the invention exerts a selective action against anaerobic bacteria by facilitating the aerobes in their attack on organic substrates. Peroxydisulphate used as taught by the present invention releases the species H2O2 and O2 into water which, unlike the prior art, are not free radicals (see W02008040987) and are particularly suitable / eligi ble for the purposes of the present invention, eliminating only the anaerobic species present in the matrices to be sanitized. In more detail, a) the high oxidation potential that characterizes peroxydisulphate (E° = 2.1 ) makes it particularly suitable for oxidizing malodorous, reducing and toxic substances; b) the reaction kinetics of peroxydisulphate in water is slower than peroxymonosulphate making its action prolonged over time and its solutions more stable; c) the S2O827H2O2 couple is able to act selectively on the anaerobic bacterial load, prolonging the deodorizing action over time, unlike the compositions reported in W02008040987 which are specifically designed to perform biocidal activity, i.e. promote the indiscriminate killing of aerobic and anaerobic species, and wherein peroxydisulphate acts in the presence of additional oxidizing agents that generate free radicals (e.g., peracetic acid, iodine I2, triiodide h'); d) peroxydisulphate is able to release in solution, by direct reaction with water, a greater quantity of oxygen than peroxymonosulphate. The surplus of oxygen is particularly useful for the aerobic bacterial load for the attack of organic substrates, favoured by the elimination of toxic malodorous compounds; and e) peroxydisulphate solutions have a slightly acidic pH (pH approximately 6). The reduced acidity advantageously allows not to break down / kill the aerobic bacterial load, thus preserving their metabolic activities. Not only that, unlike the biocidal compositions reported in W02008040987 and preferably characterized by a pH = 3.2, the reduced acidity of said persulphate solutions allows the application of the composition of the invention on delicate or pH- sensitive structures and objects.

[0061] The composition of the invention is based on the deodorizing and sanitizing action of peroxydisulphate and comprises

[0062] • at least one peroxydisulphate; and

[0063] • at least one surfactant; wherein, the at least one peroxydisulphate can be preferably selected from sodium, potassium or ammonium peroxydisulphate; and the at least one surfactant can be selected from non-ionic, anionic or cationic surfactants

[0064] Optionally, the composition of the invention can further comprise at least one pH modifying agent selected from acidifying agents and alkalizing agents, wherein,

[0065] • the acidifying agent can be citric acid, tartaric acid, malic acid;

[0066] • the alkalizing agent can be sodium bicarbonate.

[0067] The composition can be formulated as: dry mixture, mixing the ingredients of said composition in the absence of solvent; or liquid solution, dissolving said composition in water.

[0068] The dry mixture can be dispersed / released directly above / inside / under the material to be treated.

[0069] The liquid solution / dispersion can be sprayed / nebulized / poured or otherwise placed in contact with or on the material to be treated.

[0070] The composition of the invention, regardless of the formulation, is able to deodorize and sanitize smelly solid and liquid matrices of any origin, such as animal waste, solid urban waste, landfill leachate, process water from industries that treat waste from the processing of pork, cattle, sheep, chicken or other animal meat, industrial waste water, tannery water, as well as the containers of said solid or liquid matrices, and can also be used to sanitize environments, surfaces and household furnishings.

[0071] The water-soluble deodorizing and sanitizing composition can be made in the form of a kit, comprising:

[0072] • sodium, potassium or ammonium peroxydisulphate;

[0073] • a non-ionic, anionic or cationic surfactant; and

[0074] • optionally, an acidifying agent or an alkalizing agent.

[0075] It should be noted that, advantageously, the toxicity of peroxydisulphate is lower than that of peroxymonosulphate. In fact, peroxydisulphate has an acute inhalation toxicity of 590 mg / m3(compared to 50 mg / m3for peroxymonosulphate), an acute dermal toxicity of 2,248 mg / kg body weight (compared to 80 mg / kg body weight for peroxymonosulphate) and an acute oral toxicity of 30 mg / kg body weight (compared to 10 mg / kg body weight for peroxymonosulphate). Furthermore, since the composition according to the invention can be made in solid form and can be packaged in water-soluble sachets, users (professional and non-professional) are protected from unwanted direct contact with the composition, which makes the toxicity of the latter substantially negligible.

[0076] Advantageously, the formulations of the composition in aqueous solution / dispersion / suspension according to the invention are more stable over time than known liquid compositions based on peroxymonosulphates and can be used appropriately for a period of up to approximately 1 month or more.

[0077] Unlike peroxymonosulphate, peroxydisulphate does not need to be stabilized in the form of a triple salt. Therefore, when using the composition according to the invention, following the oxidation reaction of the substrates, only two moles of sulphate are advantageously released into the environment, i.e. half of those released by peroxymonosulphate. Compared to peroxymonosulphate, peroxydisulphate is easier to produce because it can be obtained electrolytically from sodium hydrogen sulphate. This reduces the environmental impact associated with the production of the composition according to the invention, as well as the costs necessary to produce the latter.

[0078] Advantageously, since peroxydisulphate is less hygroscopic than peroxymonosulphate and in solution has an almost neutral pH (about pH 6), it is not necessary to add anhydrifying compounds to the composition according to the invention and it is not necessary to adjust the pH of aqueous solutions of the composition according to the invention by adding buffering agents. All this further contributes to reducing production costs.

[0079] In the composition according to the invention, the sanitizing and deodorizing activities towards malodorous reducing substances, aided by the surfactant, derive from the oxidizing power of the S2Os27H2O2 couple, in turn aided by the O2 species that is released in water.

[0080] Advantageously, the surfactant, in addition to aiding the antibacterial activity, performs the additional function of promoting the suspension of organic materials present in complex matrices such as excretions or wastewater, thus facilitating their attack by the peroxydisulphate. Furthermore, the composition according to the invention, being able to develop O2, advantageously facilitates the biological oxidative processes carried out by the aerobic part of the bacteria. Said biological activity carried out by the aerobic component of the bacteria against polluting organic materials is further facilitated by the elimination of toxic smelly substances.

[0081] Surfactants have a key and synergistic role with respect to peroxydisulphate in the sanitizing action. In fact, being lipophilic, they bind advantageously to the bacterial wall modifying its functionality and favouring its penetration inside the cell. In this way, the selective antibacterial activity of the oxidant against the most sensitive anaerobic bacteria is significantly facilitated. More specifically, in the case that the surfactants are anionic, their presence increases the wettability especially of solid materials, facilitating the action of the peroxide. Conversely, if they are cationic, they are used only in particular cases where there is a need to reduce the total bacterial load, including the anaerobic part and the aerobic part if pathogenic, accompanied by the deodorizing action.

[0082] Antibacterial activity

[0083] The composition according to the present invention can act selectively only on the anaerobic part of the bacterial load present in the matrix to be treated only when cationic surfactants are not used, leaving the aerobic part unaltered and undisturbed in its attack on organic materials.

[0084] Antibacterial activity tests conducted on anaerobic bacteria (Actinomyces israelii) and aerobic bacteria (Escherichia coll, Staphylococcus aureus) and reported in the Examples Section, highlight this selectivity.

[0085] Not only that, as then experimentally corroborated by example 1 in the Examples Section, the surfactant used is able to significantly increase the antibacterial activity of the peroxydisulphate, advantageously conferring synergistic activity to the composition of the invention.

[0086] According to a first preferred embodiment of the invention, the individual components of the mixture are solid and are mixed together dry or are added to an aliquot of water adequate to have a final mixture of peroxydisulphate and surfactant according to the concentrations expressed below.

[0087] According to an alternative embodiment, the surfactant component is liquid and is mixed with the other solid components and the mixture is diluted in water up to the desired final concentration.

[0088] Advantageously, the various components can be packaged in a kit in suitable formats (dosage units) containing the dosed quantities to be used directly at the time of use by dissolving the component in the quantity of water necessary to give the final concentration suitable for the various types of applications.

[0089] The solid components can also be prepared in the form of granules and tablets, very practical for use in mass applications (for instance mixed with solid waste), for automatic dosing systems or for small applications.

[0090] The mixtures of the present invention, especially if used in the concentrations indicated below, act selectively only on the anaerobic part of the bacterial load present in the matrix to be treated, leaving the aerobic part unchanged, capable of continuing to attack the organic materials.

[0091] Experimental data of BOD5 determined on 100 g of pig manure treated with 1 g of sodium peroxydisulphate and 1 g of sodium lauryl sulphate and kept under agitation for 8 days showed an increase on the second day and a decrease on the fifth with a new increase of BOD5 on the seventh day that continued until the eighth day, demonstrating that in the mixture the peroxydisulphate releases oxygen that is consumed in the first five days. Furthermore, the increase after the seventh day demonstrates that the oxidative processes do not damage the bacterial load capable of attacking the organic component of the manure. This characteristic is advantageous and extremely important in the deodorization of organic materials that produce compost, in the maturation processes of animal manure that are particularly critical for the emanations of bad odors or in the treatment of the terminal organic fraction produced by mechanical biological treatment (MBT) plants of municipal solid waste (MSW) (Fig. 1 ).

[0092] Peroxydisulphate in water produces chemical species similar to those produced by peroxymonosulphate, although they derive from different types of reactions. In the case of peroxymonosulphate, oxygen is released from hydrogen peroxide and is 3.5% by weight of peroxymonosulphate, while in the case of peroxydisulphate 5.86% by weight of oxygen (significantly higher than peroxymonosulphate) is released directly into water:

[0093] 2S2O82- + 2H2O 4HSO4- + O2

[0094] S2O82- + 2H2O 2HSO4- + H2O2

[0095] The chemical equilibria described above are regulated by the presence of an excess of the respective anions characterized by different standard reduction potentials (E°). The standard reduction potential (E°) of peroxydisulphate is significantly higher than the standard reduction potential of peroxymonosulphate:

[0096] S2O82- + 2e- - 2SO42’ (E° = 2.1 )

[0097] SO52- + e- SO42’ (E° = 1 .4)

[0098] Therefore, the comparative examination of the chemical characteristics of the two peroxides shows that peroxydisulphate, in water, is able to produce H2O2 but also to directly release oxygen that facilitates the action of the aerobic bacterial load. S20s2' therefore offers the advantage of an oxidizing action significantly higher than that of peroxymonosulphate, much faster and characterized by a broader spectrum of action against smelly substrates of an inorganic nature that are more difficult to oxidize. Furthermore, peroxydisulphate is advantageously able to attack stable organic structures such as biofilms produced by bacteria, allowing disinfectants to penetrate and permanently eliminate the underlying bacterial load.

[0099] Peroxydisulphate has a crystalline structure that facilitates mixing with other solid components, such as surfactants. Furthermore, peroxydisulphate is able to passivate various metals and can therefore improve the biochemical activity of aerobic bacteria present in the matrices to be treated, for which these metals are toxic.

[0100] The composition according to the invention comprises a peroxydisulphate, a surfactant and optionally an acidifying agent or an alkalizing agent. This means that the composition according to the invention always comprises a peroxydisulphate and a surfactant, while it may or may not comprise (as will be explained in greater detail below) the acidifying agent or the alkalizing agent.

[0101] Composition comprising a non-ionic surfactant

[0102] In one embodiment of the composition according to the invention, the composition of the invention comprises: a peroxydisulphate; and a surfactant wherein, said surfactant is a non-ionic surfactant.

[0103] The peroxydisulphate has an almost neutral pH and is therefore preferentially mixable with non-ionic surfactants. In this way, a deodorizing and sanitizing composition suitable for the treatment of surfaces of pH-sensitive materials, such as those found in hospital or domestic environments, is advantageously obtained.

[0104] This embodiment of the composition according to the invention, in addition to performing the deodorizing and sanitizing action, is able to effectively attack the biofilm formed by bacteria on the surfaces, allowing any subsequent disinfectant treatments aimed at eliminating the aforementioned bacteria to be made more effective.

[0105] The nonionic surfactant may be selected from the following:

[0106] • ethoxylated nonylphenols, ethoxylated dinonylphenols, ethoxylated linear alcohols, ethoxylated dodecylphenols, ethoxylated octylphenols, alkanolamides, ethoxylated alkanolamides, ethylene oxide / propylene oxide copolymers, propoxylated ethoxylated nonylphenols, propoxylated ethoxylated linear alcohols, and mixtures thereof.

[0107] In a preferred embodiment, the nonionic surfactant comprises ethoxylated C16-C18 alcohols.

[0108] In an embodiment comprising the non-ionic surfactant, the deodorizing and sanitizing composition has the qualitative / quantitative formulation reported in the following Table 1 :

[0109] Table 1

[0110] In the aforementioned embodiment, the composition according to the invention consists of peroxydisulphate and non-ionic surfactant, i.e. it comprises only the peroxydisulphate and the non-ionic surfactant.

[0111] In an alternative embodiment of the composition according to the invention comprising a non-ionic surfactant and a peroxydisulphate, a pH regulating agent can be added, such as, for instance, an acidifying agent or a basifying agent depending on the use. For instance, the acidifying agent can be used when the composition according to the invention must have an acidic pH, preferably between 4.5-5, for instance in the case wherein it is necessary to treat human or animal excreta. In this case, the acidifying agent favourably promotes the hydrolysis of the proteins present in the excretions, which disintegrate and are attacked more easily by the peroxydisulphate. The aforementioned disintegrating action is added to the dispersing action of the surfactant on the suspended solid material, allowing for its clarification.

[0112] In an embodiment of the composition comprising the non-ionic surfactant and the acidifying agent, the deodorizing and sanitizing composition has the qualitative / quantitative formulation reported in the following Table 2:

[0113] Table 2

[0114] In the aforementioned embodiment, the composition according to the invention consists of the peroxydisulphate, the non-ionic surfactant and the acidifying agent, i.e. it comprises only the peroxydisulphate, the non-ionic surfactant and the acidifying agent.

[0115] In a preferred embodiment, the acidifying agent is citric acid, which is a product for food use and is not harmful to the environment.

[0116] Composition comprising an anionic surfactant

[0117] In another embodiment of the composition according to the invention, said composition comprises a peroxydisulphate; and a surfactant; wherein, said surfactant is an anionic surfactant, having an alkaline hydrolysis capable of imparting approximately a pH of 8-1 1 to the mixture with sodium peroxydisulphate.

[0118] This embodiment is particularly suitable in all cases wherein the alkaline pH facilitates the action of the peroxydisulphate, such as for instance in the treatment of industrial wastewater from the processing of fatty materials, such as the processing of slaughterhouses and meat preparation, possibly associated with an alkalizing agent. The alkalizing agent allows to obtain a better dissolution of fats, by the action of both the lipophilic part of the surfactant and the alkaline pH, which produces the formation of soluble salts of fatty acids.

[0119] The anionic surfactant can be selected from the following:

[0120] • salts of sodium, potassium and ammonium alkyl sulphates, salts of sodium, potassium and ammonium alkylaryl sulphates, salts of sodium, potassium and ammonium alkyl naphthalene sulphonates, salts of sodium, potassium and ammonium alkyl diphenyl sulphonates, salts of sodium, potassium and ammonium dialkyl sulfosuccinates, and mixtures thereof.

[0121] In a preferred embodiment, the composition according to the invention consists of peroxydisulphate and sodium dodecylbenzene sulphonate as an anionic surfactant.

[0122] In an embodiment comprising the anionic surfactant, a peroxydisulphate and further an alkalizing agent, the deodorizing and sanitizing composition has the qualitative / quantitative formulation reported in the following Table 3:

[0123] Table 3

[0124] In the aforementioned embodiment, the composition according to the invention consists of the peroxydisulphate, the anionic surfactant and the alkalizing agent, i.e. it comprises only the peroxydisulphate, the non-ionic surfactant and the alkalizing agent.

[0125] In a further preferred embodiment of the composition of the invention, the alkalizing agent is sodium bicarbonate, which is a product for food use and is not harmful to the environment.

[0126] Composition comprising a cationic surfactant

[0127] In an embodiment of the composition of the invention, said composition comprises: a peroxydisulphate; and a surfactant; wherein, said surfactant is a cationic surfactant.

[0128] The peroxydisulphate associated with the cationic surfactants maintains a pH between 5 and 6 and is able to simultaneously exert an antibacterial activity on both anaerobic and aerobic bacteria. This embodiment is particularly suitable for treating matrices that require, in addition to the deodorant treatment, a significant reduction in the total pathogenic bacterial load (anaerobic and aerobic).

[0129] The cationic surfactant can be selected from the following:

[0130] • n-alkyl-dimethyl-benzyl-ammonium chloride, n-alkyl-dimethyl-ethylbenzyl- ammonium chloride, dialkyl-dimethyl-ammonium chloride, alkyl-oxypropyl- dihydroxyethyl-methyl-ammonium chloride, alkyl-benzyl-imidazolyl chloride, di-quaternary cationic surfactants, and mixtures thereof.

[0131] In an embodiment comprising the cationic surfactant, the deodorizing and sanitizing composition according to the invention is qualitatively / quantitatively reported in the following Table 4:

[0132] Table 4

[0133] Said composition may further comprise at least one alkalizing or acidifying agent.

[0134] The deodorizing and sanitizing composition according to the invention can be prepared according to the formulations reported in Tables 1 - 4 and be used both as is, i.e. in solid form, and in liquid form, i.e. after mixing with water. The aforementioned solid form can comprise, for instance, powder, granules, flakes, tablets, lozenges, briquettes (briquettes of agglomerated material) and can be packaged using water-soluble capsules or sachets.

[0135] Preferably, the water-soluble composition is supplied in the form of a dry powder to be prepared in water at the time of use.

[0136] Generally, at the time of use, approximately 100 g of dry formulation are dissolved in 10 litres of water.

[0137] According to an embodiment of the invention, the water-soluble formulation comprises:

[0138] • peroxydisulphate in an amount between 25-95% w / w, preferably 60-90% w / w or 50-90% w / w;

[0139] • a surfactant in an amount between 5-75% w / w, preferably 10-40% w / w; and

[0140] • an acidifying or alkalizing agent in an amount necessary to bring the concentration of the formulation up to 100% w / w, preferably 10-30% w / w or 5-20% w / w, so as to obtain a solution in water having a pH in the range 4.5-11 when 10 g of formulation are dissolved in 1000 ml of water.

[0141] The composition according to the invention can be sprayed or spread on the solid or liquid matrices to be treated, or it can be preliminarily dissolved in water. The solution with a concentration varying between 0.1 -10% thus obtained can be sprayed on the matrices or surfaces to be treated.

[0142] In one embodiment, the deodorizing and sanitizing composition according to the invention is packaged in the form of a kit, comprising, depending on the formulation and therefore the intended use of the composition, aliquots of the following components in pre-packaged single dosage units (such as, for instance, water-soluble single-dose capsules or sachets):

[0143] - sodium, potassium or ammonium peroxydisulphate;

[0144] - a non-ionic, anionic or cationic surfactant;

[0145] - optionally an acidifying agent or an alkalizing agent - instructions for use, also available online.

[0146] The single-dose sachets may contain dosage units of each individual component or a dosage unit of the overall formulation, ready for use. Ready-to-use water-soluble single-dose sachets (5-1 Og) and capsules (0.5-1 g) will be particularly preferred. Depending on the quantities of matrices to be treated, water-soluble sachets of larger sizes (50 - 1000 g) can also be prepared; the water-soluble materials that can be used are known to those skilled in the art.

[0147] Peroxydisulphate eliminates sulphur and nitrogenous malodorous substances, both inorganic and organic, thanks to a rapid direct oxidation that causes the bad smell to disappear in a few minutes and, at the same time, inhibits the anaerobic bacterial load, thus preventing the repetition of reductive phenomena and prolonging the deodorizing action over time.

[0148] The aforementioned effect has been verified by the Inventors through experimental tests, some of which are described in the following Examples.

[0149] The composition of the invention is characterized by the fact that, when placed in an aqueous medium containing a mixture of aerobic and anaerobic bacteria, it produces a selective removal of the latter and a decrease in the BODs value of the mixture during a period of 3-6 days and a subsequent increase in said value during the following 7-8 days (Example 3).

[0150] The composition of the invention, in particular in its liquid form, allows washing, deodorizing and sanitizing means of transport of solid urban and liquid waste and can be applied in mechanical bin-washing devices to deodorize, wash and disinfect bins and containers of solid urban waste but also those of domestic or food industries.

[0151] The applications also extend to domestic uses, given the ease of use, the almost neutral non-aggressive pH and the low toxicity of the formulation. The uses extend to the deodorization, cleaning and sanitization of environments and surfaces also in the medical and hospital field, without neglecting the treatment of organic waste as such to be able to preserve it for several days before its collection.

[0152] Another advantageous application is in the deodorization and sanitization of pet litter and in the washing, deodorization and sanitization of floors and surfaces in general, in particular those of upholstery and household appliances such as refrigerators, freezers, cooktops, ovens, washing machines, dishwashers, etc.

[0153] The compositions of the present invention are very simple to use and can be applied as they are in the solid phase by dissolving the sachet containing the quantity of composition in the matrix to be treated or they can be dissolved in the necessary quantity of water and the solution obtained can be used for nebulization on surfaces or environments or added directly to the matrix to be treated whether it is solid, liquid or a suspension.

[0154] The pre-packaged format in sachets or capsules of the composition of the present invention is very useful and preferred. This format allows the reproducibility of the activity of the compositions of the invention unlike that of the powder mixtures in large formats from which the operator takes at the moment the quantity necessary to prepare the solution with the risk that the concentrations may vary considerably and may not carry out the expected activity if incorrect. In this way, waste of products spilled into the environment is also avoided.

[0155] Furthermore, these formats, not requiring significant quantities of plastic and water for the preparation of the solutions, guarantee environmental protection. Not only that, thanks to these formats it is possible to limit the volume occupied by the product and reduce pollution due to transport.

[0156] Finally, a further relevant aspect of both the compositions of the present invention and their pre-packaged water-soluble formats is that of safety, which allows any operator who uses them to not come into contact with substances that are potentially toxic in any case.

[0157] The following Examples are provided for the sole purpose of illustrating the invention and are not to be considered limiting of its scope.

[0158] EXAMPLES

[0159] Materials and methods

[0160] The tests of the adjuvant capacity of surfactants against peroxydisulphate were conducted on microorganisms from the ATCC (American Type Collection Cultures) collection of E. coll (ATCC 25922), Staphylococcus aureus (ATCC 6538P) Aeruginosa (ATCC 27853) and A.israelii (ATCC 12102). The antimicrobial activity of the mixture consisting of peroxydisulphate and non-ionic, anionic and cationic surfactants, and of the individual constituents was evaluated in compliance with European regulations: CEN European Committee for Standardization (February 1997).

[0161] Stock solutions and 10’1and 10’2dilutions of the following substances were prepared as follows: sodium peroxydisulphate (0.33%), sodium lauryl sulphate (SLS) (0.33%), lauryl dimethylbenzylammonium chloride (LDBA) (0.25%), ethoxylated / propoxylated coconut alcohol (ACEP) (0.33%), prepared in sterile distilled water and filtered drinking water, tested alone and in combination (1 %). The reagents / chemical products used were purchased from Carlo Erba.

[0162] Each sample, at different concentrations, was placed in contact with 6 mm diameter bibulous paper discs, inoculated with the bacterial strains under examination.

[0163] The determination of the oxygen available for the different oxidizing compounds can be carried out using the most common standard analytical methods, for instance for peroxydisulphate the iodometric method described in Standard Methods for the examination of Water and Wastewater APHA-AWWA-WPCF was used. The release of oxygen is particularly important to improve the action of the aerobic bacterial load present in the composting processes, treatment of animal waste, of the residual organic fraction of TMB or wastewater with a high organic content.

[0164] Example 1 - Determination of antibacterial activity

[0165] A Muller Hinton broth culture (M.H.B.-Oxid-) was prepared with a concentration of bacteria (indicated in Table 5) of 5 x 106CFU / ml at pH 6. The decrease in bacterial load produced by an aqueous solution of S20s2’ 0.24% and its dilutions 1 :2 and 10’2on the inoculum is reported in the following Table 5 in terms of residual bacterial load measured as optical density OD at 450 nm. In order to show the synergistic effect of peroxydisulphate and surfactants (a + b; a: persulphate; b: surfactant), a mixture of S20s2’ 0.24% and sodium lauryl sulphate (SLS) 0.33% was tested at a dilution of 10’2. As evident from Table 5, a decrease of 104in the anaerobic bacterial load was observed at 30" compared to the same solution without surfactant, thus demonstrating the synergistic effect. Table 5

[0166] Comparison between the decrease in bacterial load produced by a solution of S2O82and that of a mixture (a+b; a: S20s2’; b: SLS**) on an inoculum of 5 x 106CFU / ml. *Residual bacterial load ** sodium lauryl sulphate

[0167] Inoculum preparation

[0168] 18-hour Muller Hinton broth (M.H.B.-Oxoid-) cultures of the strains under examination were refreshed in 5 ml of the same medium until reaching a turbidity of 0.5 Me Farland corresponding to approximately 1x108CFU / ml, centrifuged at 5000 rpm for 10 minutes (Beckmann Centrifuge GP), and the “pellet” resuspended in the same volume of saline solution. The quantity of the inoculum was standardized by spectrophotometric measurement of the OD (optical density) at 450 nm. The quantity of the inoculum was checked by bacterial counting in agar nutrient medium.

[0169] Test execution

[0170] 20pl of the aforementioned bacterial suspensions were used to soak 6 mm diameter paper disks (used as “carriers”). The inoculum on each disk was between 5x105-5x106. Each disk was immersed in the solutions under examination at the above concentrations in water. After certain exposure times (30 sec., 2, 4, 8, 15, 30, 60, 120 min.) at a temperature of 20°C ± 2, the disks were transferred to M.H. Broth added with 1 % sodium thiosulphate used as a neutralizer, to evaluate the relative bactericidal time. The absence of turbidity in the culture medium, after 18 hours of growth at 37°C, was interpreted as the time necessary to kill the present microorganisms. Bactericidal controls were performed by sub-cultivating the samples with the relative “carriers”, in Muller-Hinton Agar plates for further 18 hours at 37°C, the absence of bacterial growth confirmed the sterility of the “carriers”. Sodium thiosulphate, at the concentration used, did not interfere with bacterial growth. The results of the tests are reported in Tables 6 and 7.

[0171] Table 6

[0172] Bactericidal times of the surfactants: Lauryl-dimethylbenzyl ammonium chloride (LDBA) (0.25%), Sodium lauryl sulphate (SLS) (0.33%) and ethoxylated / propoxylated coconut alcohol (ACEP) (0.33%). dir.: mother solution Table 7

[0173] Bactericidal times of the association of persulphate (0.33%) with Lauryldimethylbenzyl ammonium chloride (LDBA) (0.25%), Sodium lauryl sulphate (SLS) (0.33%) and ethoxylated / propoxylated coconut alcohol (ACEP) (0.33%). dir .: mother solution

[0174] From the examination of the data, the disinfectant activity of the cationic surfactant LDBA against all bacteria is evident.

[0175] Example 2 - Ability of the composition of the invention to penetrate bacterial biofilm.

[0176] In a pork meat processing plant, a series of tests were carried out both on surfaces used for processing pig parts and on the transport systems for the various parts of the animal (conveyor belts) to verify whether cleaning and disinfecting the structures was able to reduce the bacterial load or whether the bacteria were instead able to generate a protective biofilm that did not allow their elimination.

[0177] In this Example, mixtures consisting of sodium lauryl sulphate, peroxydisulphate and bicarbonate (60% / 20% / 10%) at pH 9 were used, in order to increase the detergent properties of the composition given the high content of organic materials and fats both on the processing surfaces and on the conveyor belts.

[0178] Once a swab (to be used as a “blank”) was performed on the dirty surface of the work surface, the used surface was treated with lauryldimethylbenzylammonium chloride (LDBA) (0.25%) to eliminate the bacterial load present on the surface. The repeated swab on the surface treated with LDBA demonstrated the absence of bacterial load. After 24 hours, the new swab showed the development of a new bacterial load and in this case the surface was treated with a 1 % solution of the patent composition. The swab performed 5 minutes after this treatment demonstrated a selective decrease in the bacterial load which was completely eliminated with a subsequent disinfection of the surface with the LDBA solution. Finally, after a further 24 hours, the swab was repeated on the same surface which confirmed the absence of bacterial load. The results are reported in Tables 8 and 9:

[0179] Table 8

[0180] Test performed on the work surface

[0181] Swab carried out after disinfection with LDBA Table 9

[0182] Test carried out on loins conveyor belt

[0183] Swab carried out after disinfection with LDBA The development of a new bacterial load after the first disinfection with LDBA of the surface clearly demonstrates that the bacteria were protected by the biofilm they themselves generated which did not allow the disinfectant to penetrate into the infection reservoir. The treatment of the surface with the composition of the invention attacked the biofilm and allowed the LBDA in the last application to penetrate inside and eliminate the present bacteria, as demonstrated by their absence in the swab carried out 24 hours after the application of the composition of the invention and the disinfection of the surface. The selectivity of action of the composition according to the present invention was also confirmed which, also in this case, did not completely eliminate the aerobic bacteria. Example 3-Determination of the deodorizing action

[0184] The experimental methods used to determine the deodorizing efficacy of the compositions according to the invention include colorimetric detection systems for the dosage of malodorous and toxic substances in the matrices, and an olfactometric method that uses human subjects equipped with a particularly sensitive olfactory sensory system and who are able to verify the disappearance of the bad smell from the matrices after the latter have been treated with the compositions according to the invention. In some cases, such as for instance for the waters of animal waste treatment plants or organic waste, the time necessary to eliminate the bad smell was a few minutes.

[0185] In this Example, 1 :1 mixtures of sodium lauryl sulphate and peroxydisulphate at an alkaline pH were used, in order to increase the detergent properties of the composition due to the high content of organic materials, especially fats, present in the matrices composed of meat processing waste.

[0186] Matrices of various nature were placed in suitable glass flasks, left at room temperature to simulate the normal conditions of use of the compositions and connected to the detection and dosing system consisting of Draeger vials (as described in US4160656) to determine ammonia, hydrogen sulphide, mercaptans, hydrocyanic acid and amines, after washing the entire apparatus with a nitrogen stream to eliminate any external interferences. The values obtained (expressed in ppm) fall within a wide range of concentrations depending on the matrices analysed, with high values in animal waste, for instance pig waste (H2S 50-120 ppm; mercaptans 140-360 ppm; NH3 70-1 10 ppm; HCN 1 -6 ppm), and lower and percentage-different concentrations in other matrices, such as in the leachate of a landfill (H2S 25-70 ppm; mercaptans 40-100 ppm; NH3 10-60 ppm: amines 20-70 ppm). In the matrices treated with the compositions reported below, most of the malodorous gases were found to be absent after a variable contact period, depending on the matrices and gas concentrations, ranging from 10 to 60 minutes, with the exception of animal waste, such as pig waste, wherein ammonia concentrations are very high.

[0187] 1 kg of pig waste or 1 litre of landfill leachate were treated with 10 g of a solid composition according to the invention, consisting in the first case of 50% Na2S20s, 40% ethoxylated C16-C18 alcohols and 10% citric acid and, in the second case, of 50% Na2S20s, and 50% ethoxylated C16-C18 alcohols, directly added to the matrices (pH 4.5).

[0188] The above composition is added directly to the liquid matrices and suspensions listed above in quantities greater than 0.01 % and preferably in a concentration of 0.5%-1.0% (referred to the volume of the matrices), while the solutions of the compositions are used to spray the solid materials (e.g.: municipal solid waste, MSW or surfaces), using 1 I of solution per m3of material or 1 I for approximately 100 m2of surface to be treated. The solution is dispensed using a spray system. The quantity of solution to be used may be greater in the case of washing machines. The results of the deodorization test carried out on the samples are shown in the following Table 10:

[0189] Table 10

[0190] An examination of the data clearly shows that in pig waste the concentrations of pollutants are significantly higher, in particular NH3 (the most difficult to oxidize), and in any case the composition of the present invention is able to reduce them in a short time that becomes even lower in the presence of lower concentrations as in the case of leachate and MSW. The results clearly highlight the speed of deodorizing action of the compositions and their broad spectrum of action against smelly and very toxic reducing substances. Especially in the case of animal waste, this activity is particularly important considering that pig farming is carried out in closed rooms, as is the case for other types of farming wherein it is possible to use the compositions of this invention with notable results to sanitize the environment by reducing toxic gases. A healthier environment improves the quality of the meat produced. Example 4-Selectivitv of action of the composition according to the invention on anaerobic bacteria in a natural matrix.

[0191] In order to verify the selective oxidizing action of the composition according to the invention, especially towards ammonia, said oxidizing action was highlighted by determining Kjeldal nitrogen (with a stripping and chemical dosage method), COD (chemical oxygen demand, with a titrimetric method) and nitrates (with a salicylate colorimetric method, according to Standard Methods for the Examination of Water and Wastewater ALPHA-AWWA-WPCF). The BOD5 (biological oxygen demand), which indicates the capacity of the aerobic bacterial load to degrade the organic substances present in a water sample, was determined with the respirometric method.

[0192] 1 g of the composition according to the invention was added to 100 g of fresh sewage against an untreated blank and, after mixing, the composition was left in contact with the sewage sample for 5 days.

[0193] The samples were alkalinized with 6N NaOH, NH3 was extracted by stripping with a nitrogen stream and collected in a 0.1 N H2SO4 solution that was back-titrated with 0.1 N NaOH. Nitrates were determined by the salicylate method. The treated samples showed a decrease in total Kjeldal nitrogen, which does not include nitrates in its value. This shows that the oxygen released by peroxydisulphate is consumed in the first 5 days of contact of the composition with the sewage.

[0194] COD decreases slightly, while the NH3 concentration decreases by about 50%, with an increase in nitrates of about 180% compared to the blank. The test results are shown in the following Table 1 1 :

[0195] Table 1 1

[0196] Experimental data demonstrate that: a) the peroxydisulphate of the compositions according to the invention provides the aerobic bacterial flora with a greater quantity of oxygen for the oxidation of organic substrates, this being confirmed by the decrease in Kjeldal nitrogen; b) the compositions according to the invention have the ability to oxidize ammonia, which is difficult to oxidize, transforming it into nitrate more efficiently than peroxymonosulphate, as demonstrated by the data reported below (Table 12) and relating to peroxymonosulphate.

[0197] Table 12

[0198] The above mechanism of action characterizes the compositions according to the invention and differentiates them from known disinfectant mixtures that release chlorine (as described for instance in US 4822512, W02008040987) and which are sterilizing by completely eliminating the bacterial load, whether anaerobic or aerobic.

[0199] The sample was inserted into a container equipped with a differential pressure gauge, hermetically sealed to avoid O2 exchanges, and kept at 20°C, while in this case it remained for 8 days. During the biological degradation of the organic content, O2 is consumed, and this generates a depression in the gas, measured by the manometer which, being previously calibrated, immediately returns the BOD value of the sample. In this test there is an interference linked to the production of carbon dioxide which is eliminated by adding caustic potash to the gaseous phase which chemically removes CO2. The determination was carried out using 100 g of fresh sewage added with 1 g of the composition and kept at 20°C for 8 days, recording the BOD value daily against a blank consisting of the same sample. The results are shown in Fig. 1 .

[0200] The treated samples have an increase of BOD5 in the first two days with a decrease from the fifth day and then rise from the 7th day, thus demonstrating that the oxygen released by the peroxymonosulphate is consumed in the first five days and that the aerobic bacterial load is not damaged and is able to continue the oxidative processes on the organic substrates present (Figure 1 ). In fact, COD shows a slight decrease, while the NH3 concentration decreases by approximately 40%, accompanied by an increase in nitrates of approximately 150%. The BOD5 trend shown in Fig. 1 has been confirmed in various aqueous matrices and is considered characteristic of the behaviour of the composition of the invention.

[0201] Example 5-Activitv of the compositions according to the invention on the functionality of the bacterial load and the active biomass present in Municipal Solid Waste (MSW) processed in a Mechanical Biological Treatment (MBT) plant.

[0202] A preliminary test was carried out using a continuous flow aerobic respirometer according to UNI / TS 1 1184 standards with which the potential dynamic respiration index (PDRI) was measured on waste treated with the composition according to the invention - i.e. a mixture of peroxydisulphate / ethoxylated C16-C18 alcohols (66% / 33%) - against a blank, in order to verify any modifications made to the active biomass capable of attacking the organic materials present in the Stable Organic Fraction (SOF). In fact, the PDRI measures the oxygen consumption of the biomass and therefore represents an index of the functionality of the latter.

[0203] The continuous flow aerobic respirometer (figure 6) is a known type of apparatus, comprising the following components:

[0204] • A hermetically sealed adiabatic reactor with a minimum operating volume expressed in litres, numerically equal to or less than the average size of the sample expressed in millimetres and in any case not greater than 30 mm. For instance, for a sample with an average size of less than 10 mm, the reactor volume is equal to 10 I. The reactor structure must be such as to force the incoming air to pass through the entire mass of the sample before exiting the reactor, avoiding mixing with the exhaust air;

[0205] • A system to check the tightness of the reactor;

[0206] • An aeration system equipped with a flow regulator and flow meter;

[0207] • Thermometric probes arranged to measure the temperature of the air entering and exiting the respirometer and to measure the temperature of the sample; • A system to detect the concentration of oxygen in the exhaust air (% V / V);

[0208] • A data acquisition system that allows the parameters measured at 1 -h intervals to be continuously stored. The stored data must be the average of all the values read (at least 60) during the time interval considered.

[0209] 60 kg of Stable Organic Fraction were collected and divided into 4 samples of 15 kg each. Two of the samples were not treated, thus acting as blanks, and the other two were sprayed with 1000 ml of the composition according to the invention, i.e. a 1 % solution of a mixture of peroxydi sulphate / ethoxylated C16-C18 alcohols at pH 6 (66% / 33%).

[0210] According to the procedure provided by the UNI / TS 11 184 method, a canvas bag with 1 kg of sample was soaked in a container containing 60 I of water and, after 12 h, the bag was removed and left to drip for 6 h. This operation was used to determine the amount of water to add to the sample of approximately 15 kg to bring the sample to standard humidity conditions. The volume of water thus determined was added to both the blank and the sample to be analyzed (approximately 2 to 6 I), using a sprayer in a rotating mixer to allow for correct humidification. Once humidified, the material (sample and blank) was inserted into the respirometer.

[0211] Figure 2 is a graph showing the trend of the PDRI in sample C1 and blank B1 (Series 1 = sample C1 ; Series 2 = blank B1 ) and highlights that the sample treated with the composition according to the invention has a higher oxygen consumption than the blank. It also shows that the trend of oxygen consumption increases more regularly, unlike the initial peaks shown by the blank. The aforementioned trend derives from the activation of the active biomass produced by the composition according to the invention which releases a certain amount of oxygen.

[0212] The previous Examples 1 to 5 highlight the selective inhibitory action of the composition according to the invention against anaerobic bacteria, a selective inhibitory action that is demonstrated by the disappearance of the bad odour, while the active biomass is facilitated in attacking the organic substrates both in terms of quantity and speed.

[0213] Example 6-Pilot plant experimentation A pilot plant (reactor) (figure 7) was used at an experimental level to reproduce the process conditions that are established inside the stabilization basins of a biological oxidation plant (i.e., the terminal part of a TMB plant). The experimentation allowed to determine: the residence time necessary for the stabilization of the organic fraction; the volumetric reduction of the mass; the degree of stability assessable through the PDRI.

[0214] The reactor comprises the following components:

[0215] • A containment cylinder;

[0216] • A controlled air suction system;

[0217] • A system for turning the material through a spiral screw;

[0218] • A material irrigation system;

[0219] • A drainage layer on the bottom of the cylinder.

[0220] The dimensions of the pilot plant are given in the following Table 13:

[0221] Table 13

[0222] During the experiment, the following parameters were checked: a) Turnings: they were carried out to reproduce the same conditions present in the oxidation basins, carrying out only one turning per day both clockwise and counterclockwise; b) Volumetric reduction: every day the height of the material inside the reactor was measured in order to determine the reduction factor; c) Biomass temperature: the temperature was determined inside the biomass using thermocouples positioned at different heights of the containment cylinder; d) Humidity: the humidity was checked in order to evaluate the quantity of water necessary for the oxidation process. The necessary quantity was supplied in a manner similar to that foreseen in the composting basins, i.e. during turning. The quantity of water to be supplied was determined in order to ensure biomass humidity values suitable for the stabilization process. The biomass humidity was determined twice a week; e) Intake air: the flow rate, temperature and pressure values of the air were monitored daily at a point upstream of the fan of the controlled air intake system, in a position that was as little disturbed as possible. Taking into account that the volume normally occupied by the Putrescible Organic Fraction (POF) in a basin of the Mechanical Biological Treatment (MBT) plant is equal to 7434 m3and that in the latter there are 4 fans with a maximum flow rate of 15000 m3 / h, it is obtained that the intake air flow rate is equal to 8.07 m3 / h for each m3of material present in the basin. Reporting this value for the volume of material present in the pilot plant, a nominal air flow rate of 42.7 m3 / h was obtained, corresponding to an average suction speed of 0.96 m3 / s (density D = 0.125 m).

[0223] Pilot plant dimensions

[0224] Diameter 1.5 m

[0225] Area 1 .77 m2

[0226] Height 3.7 m

[0227] Total volume 6.54 m3

[0228] The experimentation involved the execution of a preliminary test on material not treated with the composition according to the invention and to be used as blank. The material (waste) was taken from the belt that feeds the composting basins, conveying the primary under-sieve (dimensions 0-65 mm) and the secondary undersieve (dimensions 0-40 mm). The experimentation on the blank was conducted for 39 days (from 22 / 02 / 2023 to 02 / 04 / 2023), corresponding to the period of permanence of the material inside the reactor. The characteristics of the aforementioned material are reported in the following Table 14: Table 14

[0229] The following Table 15 shows the trend of biomass humidity values, determined in triplicate during the experiment and the water additions made: Table 15

[0230] * Total added water: 170 I

[0231] The humidity of the sample is essential for the optimization of the oxidation process of organic materials by the aerobic bacterial load since the water present allows the solubilization of the components and therefore their attack. The oxidation processes lead to an increase in the temperature of the materials with consequent elimination of a certain amount of water in the form of steam and therefore must be brought back to the optimal values through a series of additions, as reported in T able 15.

[0232] The trend of the degree of stabilization of the material during the experiment was monitored by respirometric analysis of samples extracted weekly, taking a sample of about 15-20 kg to be subjected to respirometric test. The results obtained are reported in the following Table 16, while Figure 3 shows the trend of the PDRI, i.e. the decrease of the latter over time:

[0233] Table 16

[0234] The data analysis highlights a fairly regular decrease in PDRI that requires 32 days to bring the materials to the correct stabilization value of about 1000 which is established by law, and which represents the limit that allows the disposal of the inertized material in landfill.

[0235] After the aforementioned preliminary test, the experimentation continued on the material to be treated with the composition according to the invention, i.e. on the sample. The pilot plant was loaded on 13 / 05 / 2023. The material (waste) was taken from the belt that feeds the composting basins, conveying the primary under-sieve (dimensions 0-65 mm) and the secondary under-sieve (dimensions 0-40 mm). The blank experimentation was conducted for 38 days (from 13 / 05 / 2023 to 20 / 06 / 2023), corresponding to the period of permanence of the material inside the reactor. The characteristics of the above material (sample) are reported in the following Table 17:

[0236] Table 17

[0237] The following Table 18 shows the trend of the biomass moisture values, determined in triplicate during the experiment, and the additions of composition according to the invention (1 % solution of peroxydisulphate / ethoxylated C16-C18 alcohols (66% / 33%) mixture) carried out (instead of the water additions foreseen for the blank): Table 18

[0238] (*) Total addition of composition according to the invention: 130 liters 1 %

[0239] The trend of humidity with a clear decrease in values already after the first 7 days indicates an increase in the speed of oxidation which however remains high and constant throughout the entire experiment. This trend is also validated by reaching a temperature of 70°C which is approximately 15°C higher than the values reached by the blank.

[0240] The degree of stabilization of the sample during the experiment was monitored by respirometric analysis of samples extracted weekly, taking a sample of approximately 15-20 kg to be subjected to respirometric testing. The results obtained are reported in the following Table 19, while Figure 4 shows the trend of PDRI, i.e. the decrease of the latter over time:

[0241] Table 19 An examination of the data clearly shows that the oxidative processes were faster, as already highlighted by the humidity trend, and consequently led to a clear decrease in the stabilization time, which was 21 days, 1 1 days less than the blank.

[0242] In order to confirm the PDRI trend, COD and TOC (total organic carbon) measurements were also carried out, whose results are reported in the following Table 20:

[0243] Table 20

[0244] The data show a regular and gradual decrease of COD in particular, of a higher magnitude than TOC, as the latter also includes substances not oxidized by the active biomass.

[0245] The examination of the data obtained in the experiment with the composition according to the invention highlights significant differences in the trend of some parameters, in particular the temperature of the active biomass and PDRI.

[0246] The temperature that developed in the sample is higher in absolute value, exceeding 70°C and remaining so for a longer period than the blank. This demonstrates a better oxidative activity of the biomass in the presence of the composition according to the invention. The aforementioned activity is confirmed by the trend of the PDRI, which shows a more regular, but above all faster, decrease than the blank, reaching a value of just over 1000 (reference value for the stabilization of SOF) in 21 days (Figure 4), i.e. about 1 1 days before the blank, which at 21 days shows an PDRI value equal to 4000 (Figure 2).

[0247] The above trend is even more important when considering the humidity values, which during the entire experiment were significantly higher for the blank than for the sample. In fact, water solubilizes the organic material, whose disintegration is facilitated by the composition according to the invention, which allows the active biomass to attack the organic material more easily, thus increasing the speed of SOF stabilization. It is therefore evident that the activation of the active biomass induced by the composition according to the invention causes a more rapid attack of the substrate due to the elimination of the malodorous reducing substances and the anaerobic bacterial load, due to the facilitation of the disintegration of the organic material and to the supply of oxygen. Confirmation of the PDRI trend comes from COD and TOC, which decrease regularly over time, confirming the attack of inorganic oxidizable substances (such as ammonia, hydrogen sulphide, mercaptans) by the composition according to the invention and its adjuvant action in the reduction of the organic load by the active biomass. This is shown in the graph in Figure 5, illustrating a comparison of the PDRI, COD and TOC trend in the sample.

[0248] The data obtained in the pilot plant test and transferred to a TMB plant allow us to state that the use of the composition according to the invention in the treatment of input material leads to an increase in the working capacity of the TMB plant of approximately 25%. Furthermore, the quality of the SOF obtained would be better both from a chemical point of view, being characterized by the absence of malodorous and toxic substances, and from a bacteriological point of view, having a lower anaerobic bacterial load, including pathogenic.

[0249] From what has been described and exemplified above, it can be stated that the deodorizing and sanitizing composition according to the invention allows to effectively overcome the drawbacks found in known deodorizing and sanitizing compositions.

[0250] Variants and / or additions to what has been described above are also possible. For instance, although the compositions previously described have been prepared on a laboratory scale, the technician in the sector is able to select and apply preparation procedures suitable for industrial scale production.

[0251] Finally, the increase of approximately 25% in the stabilization speed of the material also entails a significant economic advantage because it allows, with the same treatment times, to process 25% more MSW.

Claims

CLAIMS1. A deodorizing and sanitizing composition, comprising a peroxydisulphate, a surfactant and optionally an acidifying agent or an alkalizing agent, said composition being capable of generating an oxidizing trio consisting of S2Os27H2O2 / O2 and a pH between 4.5 and 1 1 when placed in contact with distilled water.

2. The composition according to claim 1 , wherein said peroxydisulphate is selected from the group consisting of sodium peroxydisulphate, potassium peroxydisulphate and ammonium peroxydisulphate.

3. The composition according to anyone of claims 1 -2, formulated in liquid or solid form.

4. The composition according to anyone of claims 1 -3 wherein said acidifying agent is selected from: citric acid, tartaric acid, malic acid and mixtures thereof.

5. The composition according to anyone of claims 1 -3, wherein said alkalizing agent is sodium bicarbonate.

6. The composition according to anyone of claims 1 -3, wherein said surfactant is a nonionic surfactant, preferably selected from the group consisting of ethoxylated nonylphenols, ethoxylated dinonylphenols, ethoxylated linear alcohols, ethoxylated dodecylphenols, ethoxylated octylphenols, alkanolamides, ethoxylated alkanolamides, ethylene oxide / propylene oxide copolymers, propoxylated ethoxylated nonylphenols, propoxylated ethoxylated linear alcohols, and mixtures thereof.

7. The composition according to anyone of claims 1 -3, wherein said surfactant is an anionic surfactant, preferably selected from the group consisting of sodium, potassium and ammonium alkyl sulphate salts, sodium, potassium and ammonium alkylaryl sulphate salts, sodium, potassium and ammonium alkyl naphthalene sulfonates salts, sodium, potassium and ammonium alkyl diphenyl sulfonates salts, sodium, potassium and ammonium dialkyl sulfosuccinate salts, and mixtures thereof.

8. The composition according to anyone of claims 1 -3, wherein said surfactant is a cationic surfactant, preferably selected from the group consisting of n-alkyl-dimethyl- benzyl-ammonium chloride, n-alkyl-dimethyl-ethylbenzyl-ammonium chloride,dialkyl-dimethyl-ammonium chloride, alkyl-oxypropyl-dihydroxyethyl-methyl- ammonium chloride, alkyl-benzyl-imidazolyl chloride, di-quaternary cationic surfactants, and mixtures thereof.

9. A water-soluble container containing a mixture comprising an aliquot of peroxydisulphate and an aliquot of surfactant such that the mixture is capable of generating an oxidizing trio consisting of S2Os27H2O2 / O2 and a pH between 4.5 and 1 1 when placed in contact with water.

10. The water-soluble container according to the previous claim which is a prepackaged single dosage unit chosen from: capsules, single or multi-dose sachets.

11. A process for deodorizing and sanitizing materials and / or surfaces and / or environments comprising the steps of:• preparing a mixture by mixing with each other a rate of peroxydisulfate and a rate of a surfactant;• mixing the resulting mixture with the material to be treated; or alternately preparing with said mixture an aqueous solution and applying it on the material or surface to be treated or dispersing it or spraying it in the environment to be treated; said mixture being able to generate an oxidant trio consisting of S2Os27H2O2 / O2 and a pH between 4.5 and 1 1 when in contact with water.

12. Use of a composition comprising peroxydisulphate and a surfactant to deodorise and sanitise matrices, said mixture being capable of generating an oxidising trio consisting of S2Os27H2O2 / O2 and a pH between 4.5 and 1 1 when placed in contact with water and said oxidising trio acting to deodorise and sanitise said matrices.

13. The use according to the preceding claim for the selective elimination of anaerobic bacteria contained on the surface and inside matrices to be sanitised and deodorised.

14. The use according to anyone of claims 12-14 wherein the composition is in solid or liquid form.

15. The use according to the preceding claim which is mixed or spread on the matrix to be treated or is dispersed or sprayed or nebulised on the matrix or in theenvironment to be treated.

16. The use according to anyone of claims 12-15 wherein the matrices are chosen from said matrices being chosen from solid and liquid materials, surfaces, containers and environments.

17. The use according to anyone of claims 12-16 wherein the matrices are chosen from animal excrement, solid urban waste, landfill leachate, industrial process waters in general, in particular those that treat waste deriving from the processing of animal meat, tannery waters, industrial waste waters, as well as the containers of said solid or liquid matrices.

18. The use according to anyone of claims 12-17 wherein the materials, surfaces and environments are of a domestic type and are: organic waste, pet litter, floors and surfaces in general, in particular upholstery and household appliances such as refrigerators, freezers, cooktops, ovens, washing machines and dishwashers, means of transporting solid waste, mechanical bin-cleaning devices, bins and containers for urban and domestic waste.

19. A kit for use according to anyone of claims 12-18, comprising a mixture comprising peroxydisulphate, a surfactant and optionally an acidifying agent or an alkalizing agent, said composition being capable of generating an oxidizing trio consisting of S2Os27H2O2 / O2 and a pH between 4.5 and 1 1 when placed in contact with distilled water, said mixture being packaged in single-dose or multi-dose dosage units, together with instructions for use, also accessible via the web.

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