"Deodorizing and sanitizing compositions"

Field of the invention

The present invention relates to peroxide-based deodorizing and sanitizing compositions. The invention also relates to their preparation and formulation in kits and their use for neutralising foul-smelling substances and toxic gases and for sanitization.

Background art

The problem of the emission of bad odours is very extensive and embraces numerous categories of compounds present in liquid, solid or gaseous matrices. The difficulty of their elimination is related to the physical state of the material emitting the odour, and therefore multiple products have been prepared for the various different applications. Nevertheless, to date, no simple, easily producible compositions are available from the industrial point of view that are capable of deodorizing and disinfecting the various types of materials.

Control of odours is a very great problem, given the substantial variety of volatile substances responsible for the odours and the very considerable numbers of processes that generate them, often deriving from the activity of bacteria, particularly anaerobes, that give rise to foul-smelling and often toxic reduction products. The problem is particularly evident on livestock breeding farms where it takes on very notable proportions, but also in sanitary and industrial environments as well as in domestic ones, due to the steadily increasing presence of domestic animals of various types. Furthermore, the control and removal of foul-smelling liquid and solid materials and gases is of particular interest in the context of environments and machinery related to urban waste collection and disposal activities.

There are also problems related to the disposal of animal excreta present in the home for which, for example, sizeable specific litters are

used that absorb or are mixed with the excreta and then have to be disposed of. The control of foul-smelling emissions is therefore a particularly strongly perceived problem and one which currently has not been resolved in a satisfactory manner and is believed to require the availability of products obtained with economic, low-toxicity formulations for users and the environment, products which are also endowed with antibacterial activity and are easily manageable by inexpert people such as elderly subjects and children.

It should be recalled, moreover, that foul-smelling substances generally also have a high microbial load and therefore, necessarily, the formulations to be used should be simultaneously deodorizing and disinfecting, or at least such as to lower the microbial load of the materials treated.

Most of the known methods use scented substances to eliminate the bad odours, which, however, act only by masking them, superimposing themselves upon them but not eliminating them, reacting with them and converting them to odourless and non-toxic or less toxic substances.

There are also formulations in which compounds are present which are capable of reacting with the foul-smelling volatile substances, such as enzymes, bacteria, metal transition complexes or amphoteric products added with antibacterial substances, but these formulations are generally complex, sometimes risky to use and often expensive.

Most foul-smelling substances belong to the following categories: volatile compounds of an acid nature, such as sulphurated hydrogen and other sulphur-based compounds, including the mercaptans; volatile compounds of an alkaline nature, such as ammonia and amines and, more generally, compounds deriving from decomposition/putrefaction processes;

aldehydes and ketones and, more generally, organic compounds more or less emitting disagreeable odours.

The problem of deodorization has been addressed in WO 2006/137821, preparing liquid mixtures based on cocamidopropyl betaine, an amphoteric surfactant to which can be added solvents, acids and salts, e.g. salts of ethoxy alcohols, such as, for example, sodium lauryl ethoxy sulphate. To the mixtures are added a stabilising agent, citric acid, dihydrated sodium citrate and water. Other components can also be added as fragrances, Particular attention must be paid in their preparation in order to control the viscosity which must not exceed the critical values for the purposes of their use, for example as sprays, acting also on the temperature. The mixtures are modified as a function of the type of substrate to be treated and are capable of forming complexes with the gas molecules, neutralising a very extensive range of inorganic, acidic and basic compounds, as well as organic substances such as aldehydes, carboxylic acids and amines. The mixtures are also capable of exerting a bactericidal action by adding Triclosan, a bacteriostatic agent active against Gram-positive and Gram-negative bacteria. However, attention should be drawn to the complexity of the preparation of the mixtures described in WO 2006/137821, the modifications needed to be made to them for better application in the wide range of substrates, and the flocculating capacity of the materials in suspension, which is not always useful. In fact, in the case of suspended organic materials, their partial prior decomposition would be useful with clarification of the matrix to allow better chemical attack by the bacterial load present (e.g. animal excreta). Moreover, their disinfectant action requires the addition of a further compound to the basic mixture.

Compounds and formulations based on oxidising agents can be used in the case of foul-smelling products of a reducing nature (e.g. sulphurated hydrogen, ammonia) and also many organic substances can be oxidised (e.g. aldehydes, ketones, amines) and thus peroxides of various types are often present in the formulations. The high reactivity

of oxidants, however, generally makes their aqueous solutions poorly stable and thus the formulations in aqueous solution often require the addition of stabilising substances, chelants of metals that catalyse the redox reactions or pH modification, often in a distinctly acidic direction. Among the known oxidants, the peroxides are often used, and especially the persulphates owing to their substantial oxidation potential which makes them particularly reactive towards many substances.

In US 6,028,045 a study is reported which revealed that the aqueous solutions of the persulphates are poorly stable, particularly if the pH value is 2 or more and if substances are present that catalyse their decomposition. pH was therefore blocked between 0 and 0.9 by means of the addition of methanesulphonic or sulphuric acid to maintain it between 0.2 and 0.7 and free radical blockers (radical scavengers) were added (e.g. dihydroxybenzenes and their analogues) responsible for catalysing the decomposition of peroxides, also using deionised water so as not have in solution the cations present in drinking water, which are catalysts of decomposition. To the solutions is added preferably an emulsion of two non-ionic detergents as additional stabilisers.

The stability tests of the solutions at pH 0.2 or 0.5 revealed a duration of 12 weeks without any loss of oxidising power, while no stability tests over lengthier periods were reported. The persulphate preferably used is potassium peroxymonosulphate (potassium monopersulphate triple salt) present in a composition known as Caro's reagent. The applications reported relate to laundries, household cleaning, and particularly toilet cleaning, whereas no mention is made of any deodorizing capacity.

The stability of these solutions is unquestionably quite long-lasting if we bear in mind that the persulphates in aqueous solution lose more than 50% of their oxidising power within the space of one week, but the stability invariably proves limited for a large-scale application. There are, moreover, other limitations in terms of application deriving

from the distinctly acidic pH, which is too aggressive for various types of materials, and from the need to use deionised water for the preparation.

An application of peroxymonosulphate in aqueous solution for the treatment of the liquid phase of manure and for neutralising the toxic gases generated by it is reported in US 4,160,656. Various peroxides were experimented with, such as peracetic acid, which, however, leaves a strong acetic acid odour, and Hydrogen peroxide at pH 4-8, which decomposes too quickly. Formaldehyde alone has yielded no results, whereas, when combined with hypochlorite, it yields excellent deodorization, but has been discarded both because the two components need to be added separately to the liquid manure and because toxic chlorine dioxide may be formed. Formaldehyde was therefore combined with various oxidants such as hydrogen peroxide and peroxymonosulphate, which enable a single solution to be prepared by blending the two components immediately prior to use. The drawbacks of this application stem from the irritant action of formaldehyde, as disclosed by the authors themselves, from the use of poorly stable aqueous solutions and from the modalities of use of the mixture which involves the preparation of two separate solutions to be blended immediately prior to use.

Pertaining to the context of solid formulations of disinfectants are the compositions described in US 4,822,512, containing peroxymonosulphate in triple salt form (2KHSOs. KHSO ₄ . K2SO4 "Caroat" or Caro's reagent or Oxone) capable of oxidising the sodium chloride added and allowing the development of chlorine in solution. Also present in the compositions are sulphamic acid, a blocker of the chlorine developed, sodium hexamethaphosphate as a pH buffer and metal chelant, malic acid and sodium dodecylbenzenesulphonate as a detergent. The action of the preparations is bactericidal and virucidal and their application is in the field of detergents and disinfectants for surfaces and objects.

The need for a pH of around 2 in the solution to allow better development of chlorine, however, makes the solutions aggressive towards many materials, bearing in mind also the presence of a further powerful oxidant such as peroxymonosulphate. Moreover, the presence of chlorine does not make the preparations suitable for environmental applications, given the possibility of the formation of potentially toxic organic chlorine derivatives.

Other solid formulations based on peroxymonosulphate triple salt, in combination with other components to obtain granules or tablets for dish-washers are described in US 5,559,089. Peroxydisulphate failed to yield good results unlike peroxy-monosulphate, which was assayed in the form of a salt with various cations, including organic cations. The mixtures prepared are very complex owing to the needs deriving from the particular application and entail the presence not only of Oxone, but also of enzymes, detergents, organic dispersing agents, agents for bringing pH into the alkaline range, agents for the removal of chlorine, organic emulsifying agents, organic sequestering agents containing nitrogen, anionic and non-anionic surfactants with a low foam content.

In the state of prior art the deodorizing power of the products described has never been reported nor even directly taken into consideration in the description of the invention products. The compositions and products in the state of prior art are basically aimed at achieving a distinctly antibacterial, antiviral and disinfecting action without any particular or specific deodorizing action.

As is generally understood, "to disinfect" means to "destroy all the possible microbes of any type present in an inert object", whereas what is meant by the expression "to sanitize" is to "render physically clean and substantially reduce, in the best and most practical way, agents that may prove damaging to health ".

There was therefore a strongly perceived need for the availability of compositions with an effective deodorizing and sanitizing action capable of overcoming the problems mentioned above.

In the description here below percentages are expressed throughout as percentages by weight, unless otherwise specified.

Summary of the invention

It is an object of the present invention a deodorizing and sanitizing composition comprising a basic mixture of components (a+b) in which the a:b ratio ranges from 1:4 to 4:1. Preferably the composition comprises: a) a peroxide in amounts ranging from 20 to 80% of (a+b); b) a surfactant (selected from the group consisting of anionic, cationic and non-ionic surfactants) in amounts ranging from 80 to 20% of (a+b); c) an alkalinising agent (selected from the group consisting of water-soluble salts and bases) suitable for producing a pH in water ranging from 1.5 to 8.5 when in the presence of the other components of the mixture, preferably pH ranging between 2.0-7.5, more preferably from 2.5 to 7.0, and even more preferably around 4.5-7.0. Preferred agents are, for example, buffer substances such as the bicarbonates, added in amounts ranging from 0 to 20% of the basic mixture (a+b), preferably 0.05-0.15%; d) natural or synthetic zeolites, preferably clinoptylolite and/or zeolite A, added in amounts ranging from 0 to 50%, preferably from 10% to 40% of the basic mixture (a+b); e) oxidimetric colouring agents, in amounts ranging from 0 to 0.01%, preferably 0.001-0.003% of the basic mixture (a+b).

Another object of the invention is the process for the preparation of the composition in liquid phase, comprising the steps of blending the individual components and adding them to a given quantity of water to obtain a final solution in which the basic mixture (a+b) has a

concentration of 0.05-10%, preferably 0.5-1.5%.

Yet another object of the invention is the process for the treatment of materials and/or environments comprising the step of mixing the composition of the invention (in the liquid or solid state) with the material to be treated or spraying or nebulising the liquid composition as an aerosol in the environment to be treated.

A further object of the invention is a deodorizing and sanitizing kit containing the components of the composition in solid form and/or in a concentrated solution to be diluted in water.

Yet a further object of the invention is the use of a combination of a peroxide and a surfactant to deodorize environments and/or manufactured objects or substrates.

Further objects will be evident from the following detailed description of the invention.

Detailed description of the invention

The invention relates to a solid or liquid composition with a broad spectrum of applications, capable of eliminating foul-smelling odours from solid or liquid matrices of various natures such as: excreta, solid urban waste (SUW), rubbish or waste dump percolate, industrial processing waters in general, particularly those treating animal waste residues deriving from the processing of the meat of pigs, cattle, sheep, chickens or other animals, tannery waters, industrial effluent waters, as well as from the containers of said solid or liquid matrices. It is also capable of exerting a sanitizing action. The applications may extend to domestic uses, given the simplicity of use and low toxicity of the formulations. The mixture is characterised by the presence of an oxidant, for example, peroxymonosulphate, by a surfactant and possibly by a zeolite and a colouring agent can be advantageously

added which performs the function of indicating the activity of the composition when formulated in an aqueous mixture.

The deodorizing action of the compositions according to the invention derives from the synergistic combination of the peroxides and surfactants which, if anionic, increase wettability, particularly of solids, and thus facilitate the action of the peroxides, or, if cationic, boost the inhibitory action of the peroxides against anaerobic bacteria responsible for the production of foul-smelling and toxic substances. Anionic surfactants also exert a synergistic action for the antibacterial activity of the compositions in that, being lipophilic, they bind to the bacterial wall, modifying its functionality and facilitating penetration of the oxidant into the cell and thus its action.

The oxidising compounds are preferably selected from the group consisting of inorganic peroxides such as: hydrogen peroxide, permanganates, percarbonates, perborates, metal dioxides, urea peroxyhydrate, percarboxylic acids, such as peracetic or perpropionic acid, salts of peroxydisulphate, such as ammonium peroxydisulphate and potassium peroxydisulphate, salts of peroxymonosulphate, such as sodium peroxymonosulphate, potassium peroxymonosulphate, ammonium peroxymonosulphate, magnesium peroxymonosulphate, quaternary ammonium peroxymonosulphate, and carboxylic acid peroxymonosulphate. Particularly preferred is potassium peroxymonosulphate triple salt or Caro's reagent (2KHSO5.KHSO4.K2SO4) available on the market as Oxone® by DuPont or Sigma-Aldrich and Caroat® by Degussa. Particularly preferred is the product commercially available as Oxone in that it is easily obtainable on the market and at low cost.

The formulation of the oxidant as a triple salt (2KHSO ₅ -KHSO ₄ -K ₂ SO ₄ ) (Caro's reagent) manifests substantial stability in the solid phase, even when mixed with organic substances as potential oxidation substrates, such as surfactants, carboxylic acids or amine compounds..

Peroxymonosulphate possesses the characteristic dual advantage of being capable of acting both as a direct oxidant on the substrates and of producing hydrogen peroxide in aqueous solution giving rise to an unquestionably more active mixture consisting of peroxymonosulphate and hydrogen peroxide.

The peroxymonosulphates possess the additional advantage of yielding sulphates as reaction products which are not toxic either for living beings or for the environment.

The anionic surfactants are preferably selected from the group consisting of alkylsulphonate and alkylarylsulphonate salts, alkylsulphate and alkylarylsulphate salts, alkylnaphthalene- sulphonate and alkyldiphenylsulphonate salts, and dialkylsulpho- succinate salts.

Particularly preferred are the alkylsulphate and alkylarylsulphate salts of sodium, potassium and ammonium; of the cations of protonated mono-, di- and tri-ethanolamines or protonated isopropylamines; the alkylnaphthalenesulfonate and alkyldiphenylsulphonate salts of sodium, potassium and ammonium; the dialkylsulphosuccinate salts of sodium, potassium and ammonium, of the cations of protonated mono-, di- e tri-ethanolamines or of protonated isopropylamines. Particularly preferred is sodium dodecylbenzenesulphonate.

The cationic surfactants are preferably selected from the group consisting of n-alkyldimethylbenzylammonium chloride, n- alkyldimethylethylbenzylammonium chloride, diachildimethyl- ammonium chloride, alkyloxypropyldihydroxyethylmethylammonium chloride, alkylbenzylimidazolyl chloride and the diquaternary cationic surfactants known as Diquat.

The non-ionic surfactants are 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, ethoxylated propoxylated nonylphenols, ethoxylated propoxylated linear alcohols.

The colouring agents that can be advantageously used in the compositions according to the invention are selected from the group consisting of all those substances capable of manifesting colour changes (preferably visually detectable) in the presence of a changing (decreasing) of the oxidising power of the composition. The amount to be added is a function of the intensity of colour one wishes to confer upon the final mixture, for the purposes of making the colour change more evident.

The colouring agents are preferably selected from the group consisting of oxidimetric indicators such as, for example: diphenylamine, diphenylbenzidine, indigo derivatives, phenothiazines or safranines. Particularly preferred is amaranth.

The zeolites are preferably selected from the group consisting of natural zeolites, preferably clinoptylolite, or synthetic zeolites, preferably zeolite A, preferably additioned to increase the adsorbent power of the composition and enhance its deodorizing power.

The formulations in liquid form can be obtained by dissolving the various components a)-e) in water, typically at the time of use. The liquid formulations are stable for very long time periods; their activity is indicated by the colouring agent, the colouring intensity of which diminishes when the oxidising power drops below the desired limits, typically below 50% of the initial oxidising power.

The pH of the liquid compositions typically ranges from 2.0 to 2.5 and this type of formulation can be used as is in the case of applications on matrices that are not damaged by a distinctly acidic pH. In any event, the pH can be brought to neutrality by means of the addition of an alkalinising agent, for example a water-soluble salt or base, typically a

buffering agent, such as, for example, a bicarbonate, generally potassium, sodium or ammonium bicarbonate The amounts vary as a function of the agent used. By way of an example, the amounts are typically 0.05 to 0.15% of (a+b) and the deodorizing and sanitizing capacity of the compositions is unaltered, thus allowing their use on more delicate and pH-sensitive matrices or for increasing their safety, as in the case of domestic uses.

According to a first embodiment of the invention, the individual components of the mixture are solid and are blended dry or are added to an aliquot of water adequate for achieving a final mixture of (a+b) according to the concentrations expressed above. According to an alternative embodiment, component b) is liquid and is blended with other solid components and the mixture is diluted in water until the desired final concentration of (a+b) is achieved.

Advantageously, the various components from a) to e) can be packaged in suitable formats (dosage units) containing the metered amounts to be used directly at the time of use for dissolving the component in the amount of water needed to produce the appropriate final concentration for the various types of applications.

The solid components can also be prepared in the form of granulates and tablets, which are very practical when used for applications on masses (for example, mixed with solid waste), for automatic metered dose systems or for small applications.

The eventuality of direct reactions between the peroxide and the organic substances in the blending operation needed for the preparation of the mixtures led to a study being conducted on the formation of explosive powder mixtures by means of thermal analysis of the individual components and the mixture. Sodium lauryl sulphate presents a fusion endotherm at 80-100 ⁰ C and exothermal decomposition at temperatures above 200 ⁰ C. Caro's reagent presents a decomposition esotherm at 140-200 ⁰ C (peaking at 182°C) with great

development of heat. Analysis of a mixture consisting of 33% sodium lauryl sulphate and 66% Caro's reagent presents a first fusion at 110- 12O ⁰ C (peaking at 115.8 ⁰ C) followed at 140-200 ⁰ C by a decomposition attributable to the decomposition of the Caro's reagent present in the mixture. Impact tests were performed to determine the mechanical impact sensitivity corresponding to the energy of 300 kg/cm ² without any changes occurring in the mixture. This trend demonstrates that the presence of the surfactant has had no effect on the peroxide decomposition process and confirms the absence of any risk in the preparation of solid compositions and the substantial stability of the compositions even at high temperatures and in response to impact.

The mixtures according to the present invention, if used at the concentrations indicated above (0.05-10%), are capable of acting selectively only on the anaerobic part of the bacterial load present in the matrix to be treated, leaving the aerobic part unaltered and capable of continuing its attack on the organic materials. Experimental BOD5 data determined on 100 g of pig excreta treated with 1 g of Caro's reagent and 1 g of sodium lauryl sulphate and held under stirring for 10 days showed an increase on the second day and a decrease on day 5 with a new increase in BOD5 on day 8, showing that, in the mixture, the peroxymonosulphate releases oxygen that is consumed in the first 5 days. Moreover, the increase after day 8 demonstrates that the oxidising processes do not damage the bacterial load capable of attacking the organic component of the excreta. This characteristic proves extremely important in the deodorization of organic materials that produce compost in animal excreta maturation processes which are particularly critical for the emission of bad odours. For these purposes the preparations according to the present invention and containing cationic surfactants combined with the peroxide prove even more active.

The compositions according to the invention, whether used in the solid or even in the liquid state, manifest a broad spectrum of applications

capable of eliminating the bad odours emitted by solid and liquid matrices of various natures.

The formulations can be prepared in kits ready for use and containing the following components in defined amounts, packaged singly or in blended mixtures, possibly dilutable in water: a) an aliquot of peroxide; b) an aliquot of surfactant; c) possibly an aliquot of an alkalinising agent; d) possibly an aliquot of zeolite; e) possibly an aliquot of a colouring agent; f) instructions for use.

The formulations are easy to prepare, possess low toxicity, are practical to use, even in the domestic context and have a broad spectrum of action.

The compositions according to the present invention manifest a broad spectrum of action and are capable of deodorizing and sanitizing foul- smelling solid and liquid matrices of any origin, such as animal excreta, solid urban waste, rubbish dump and waste tip percolate, processing waters of industries that treat animal residues from the processing of the meat of pigs, cattle, sheep, chickens and other animals, and industrial effluent waters.

For uses in the context of SUW an a:b ratio of approximately 1:1 is preferable in order to increase the detergent capacity against organic materials. This mixture makes it possible to wash, deodorize and sanitize the means of transport of solid urban waste and liquid waste and can be applied in mechanical bin-washing devices to deodorize, wash and disinfect the bins and SUW containers, as well as household or food industry waste bins and containers.

The applications also extend to domestic uses, given the simplicity of use, the possibility of modifying pH so as to make it less aggressive

and the low toxicity of the formulation. The uses extend to the deodorizing, cleansing and sanitizing of environments and surfaces, to the treatment of the organic component of waste so as to conserve it for several days prior to collection, in the deodorizing and disinfection of domestic animal litters, and in the washing, deodorizing and disinfection of floors and surfaces in general, particularly those of wallpapers and coverings, upholstery and household electrical appliances such as refrigerators, freezers, cooking plates, ovens, washing-machines, dish-washers, etc.

The compositions according to the present invention are very simple to use and can be applied as is in the solid phase by pouring the amount of powder necessary for the matrix to be treated or can be dissolved in the necessary amount of water and the solution obtained can be used for nebulisation and spraying on surfaces or environments or added directly to the matrix to be treated, be it a solid, liquid or suspension.

The components of the mixtures present very low toxicity, are non- irritant and do not generate allergies.

The following examples are provided to illustrate the invention and are not to be regarded as limitative of the scope of the invention.

Determination of available oxygen

The determination of the oxygen available for the various oxidising compounds is quite easily done using the most common standard analytical methods; for example, in the case of monopersulphate, also present in the triple salt (or Caro's reagent) the iodometric method was used.

In the case of monopersulphate present as triple salt or Caro's reagent (2KHSO5.KHSO4.K2SO4) a conversion factor can be established between available oxygen and the percentage of monopersulphate in the compositions according to the following calculation:

- molecular weight of the triple salt = 614.74 g/mol

- molar fraction of oxygen in the pure triple salt = 32/614.74 in which 32 corresponds to two moles of O per mole of triple salt corresponding to the two moles of potassium monopersulphate present in the Caro's reagent;

- % of oxygen available = (32/614, 74)* 100 = 5.21%.

If, in one of the compositions according to the invention, only the monopersulphate is present and has an available oxygen value of 1.21%, the percentage of triple salt by weight contained in the composition is given by: 1.21/0.0521 = 23.22%.

The percentages of available oxygen released by the compositions according to the present invention as a function of pH from 2 to 7 vary from 1% to 3.5%, and are very different from those used for application in dish-washing machines (US 5,559,089), a greater oxygen availability being necessary to activate the oxidative processes of the oxidisable foul-smelling substances, cut down the anaerobic bacterial load and, finally, facilitate the aerobic bacteria in their processes of attacking the organic matrices.

Determination of deodorizing action

The experimental methods used to determine the efficacy of the compositions were of two types, namely, the use of colorimetric detection and assay systems for foul-smelling and toxic substances in the matrices, and testing by means of the olfactory sensory system of a number of subjects.

Matrices of various natures were placed in suitable glass flasks, left at room temperature to simulate the normal conditions of usage of the compositions, connected up to the detection and assay system consisting of Drager ampoules (US 4,160,656), for the determination of ammonia, sulphurated hydrogen, mercaptans, cyanhydric acid and

amines, after washing the entire apparatus with a nitrogen current to eliminate any external interference. The values obtained fall within a broad range of concentrations as a function of the matrices analysed with high values in animal excreta, for example, pig excreta (H2S 60- 110 ppm; mercaptans 150-350 ppm; NH ₃ 60-100 ppm; HCN 1-5 ppm) and lower and different percentages in other matrices such as, for example, in the percolate of a rubbish dump (H2S 20-80 ppm; mercaptans 50-110 ppm; NH3 10-50 ppm: amines 20-80 ppm). In matrices treated with the compositions reported here below most of the foul-smelling gases were found to be absent after a variable period of contact, according to the matrices and gas concentrations, ranging from 10 minutes to two hours, except for animal excreta, such as those of pigs, in which the ammonia concentrations are very high. To verify the selective oxidising action against ammonia, this was determined with a chemical stripping and assay method, together with Kjeldal nitrogen, BOD5, COD and nitrates to assess the extent of the oxidation. To 100 g of fresh manure was added 1 g of the compositions against an untreated blank and, after mixing, was left in contact for five days. The samples were alkalinised with NaOH 6N and NH3 was extracted by stripping with a nitrogen current and collected in a solution of H2SO4 0.1N which was back-titrated with NaOH 0.1N. Nitrates were determined using the salicylate method. The treated samples showed a reduction in Kjeldal nitrogen which does not include the nitrates in its value, an increase in BOD5 in the first two days with a reduction on day 5 only to rise again, showing that the oxygen released by the peroxymonosulphate is consumed in the 5 days and that the aerobic bacterial load is not impaired and is capable of proceeding with the oxidising processes on the organic substrates present. COD shows only a slight reduction, while the NH3 concentration diminishes by approximately 40%, accompanied by an approximately 150% increase in nitrates.

Kjeldal BOD ₅ COD NH ₃ NO ₃ g/l N ₂ mg/1 O2 mg/1 O2 g/i N ₂ mg/1

Blank 1.30 850 2530 1.25 1.01

Sample 0.60 590 2420 0.75 2.55

The experimental data demonstrate (i) that the peroxide supplies the aerobic bacterial flora with a greater amount of oxygen for oxidising the organic substrates, as confirmed by the reduction in Kjeldal nitrogen, (ii) that the compositions selectively inhibit the anaerobic bacterial flora responsible for the production of toxic and foul-smelling substances and (iii) that the compositions are also capable of oxidising ammonia, which is harder to oxidise, by converting it to nitrate. This mechanism characterises the compositions and distinguishes them from disinfectant mixtures that release chlorine and prove sterilising, completely eliminating both the anaerobic and aerobic bacterial load (US 4,822,512).

The second method was developed by selecting a number of subjects endowed with a particularly sensitive olfactory sensory system who verified the disappearance of the bad odour from the matrices after the latter had been treatment with the compositions. In some cases, as with the waters of animal residues or organic waste treatment plants, the time needed to eliminate the bad odour was just a few minutes..

Example 1

a) Solid compositions were prepared consisting of 20% anionic surfactant, 80% peroxide and 0.001% amaranth colouring.

The surfactant was sodium lauryl sulphate and the peroxide was selected from the group consisting of the peroxymonosulphates of potassium, sodium, ammonium, magnesium, quaternary ammonium and carboxylic acids. The solid compositions were preferably used at concentrations from 0.05% to 10% by weight in aqueous solutions prepared at the time of use, and their activity remained substantially unaltered for approximately seven days.

b) Solid compositions such as in example Ia, but containing 30% surfactant and 70% peroxide were added with 0.1% potassium

bicarbonate to bring the pH to neutrality. The solid compositions were preferably used at concentrations from 0.05% to 10% by weight in aqueous solutions prepared at the time of use, and their activity remained substantially unaltered for approximately seven days

Example 2

a) Solid compositions were prepared consisting of 35% anionic surfactant, 65% peroxide and 0.003% amaranth colouring.

The surfactant was sodium lauryl sulphate and the peroxide was potassium peroxymonosulphate triple salt or Caro's reagent (2KHSO ₅ -KHSO ₄ -K ₂ SO ₄ ) commercially available as Oxone® by DuPont or Sigma-Aldrich and Caroat® by Degussa. The solid compositions were preferably used at concentrations from 0.05% to 10% by weight in aqueous solutions prepared at the time, and their activity remained substantially unaltered for approximately seven days.

b) Solid compositions constituted as in example 2a added with 0.1% potassium bicarbonate to bring the pH to neutrality. The solid compositions were preferably used at concentrations from 0.05% to 10% by weight in aqueous solutions prepared at the time, and their activity remained substantially unaltered for approximately seven days.

Example 3

a) Solid compositions were prepared consisting of 65% cationic surfactant, 35% peroxide and 0.001% amaranth colouring. The surfactant was cetrimonium chloride lauryl dimethylbenzyl- ammonium chloride and the peroxide was selected from the group consisting of the peroxymonosulphates of potassium, sodium, ammonium, magnesium, quaternary ammonium and carboxylic acids. The solid compositions were preferably used at concentrations from 0.05% to 10% by weight in aqueous solutions prepared at the time of

use, and their activity remained substantially unaltered for approximately seven days.

b) Solid compositions consisting of 60% cationic surfactant, 40% peroxide and 0.001% amaranth colouring were prepared. The surfactant was lauryl dimethylbenzylammonium chloride and the peroxide was potassium peroxymonosulphate triple salt or Caro's reagent (2KHSOs. KHSO4.K2SO4) commercially available as Oxone® by DuPont or Sigma-Aldrich and Caroat® by Degussa. The solid compositions were preferably used at concentrations from 0.05% to 10% by weight in aqueous solutions prepared at the time of use, and their activity remained substantially unaltered for approximately seven days.

c) Solid compositions constituted as in example 3a and 3b added with 0.15% potassium bicarbonate to bring the pH to neutrality. The solid compositions were preferably used at concentrations from 0.05% to 10% by weight in aqueous solutions prepared at the time of use, and their activity remained substantially unaltered for approximately seven days.

Example 4

a) A series of liquid compositions were prepared consisting of 20 to 80% of 60-80% cationic surfactant solution, to which were added 20-80% peroxide and 0.001-0.005 amaranth colouring at the time of use. The surfactant was lauryl dimethylbenzylammonium chloride and the peroxide was selected from the group consisting of the peroxymonosulphates of potassium, sodium, ammonium, magnesium, quaternary ammonium, and carboxylic acids. The liquid compositions were preferably used at concentrations from 0.05% to 10%, and their activity remained substantially unaltered for approximately seven days.

b) Liquid compositions as in example 4a were modified by replacing the peroxymonosulphate with Caro's reagent (2KHSO5.KHSO4.K2SO4) available commercially as Oxone® by DuPont or Sigma-Aldrich and Caroat® by Degussa. The liquid compositions were preferably used at concentrations from 0.05% to 10%, and their activity remained substantially unaltered for approximately seven days.

c) Liquid compositions constituted as in example 4a and 4b added with 0.05-0.15% potassium bicarbonate to bring the pH to neutrality. The liquid compositions were preferably used at concentrations from 0.05% to 10%, and their activity remained substantially unaltered for approximately seven days.

Example 6

The compositions as in examples Ia, Ib, 2a, 2b, 3a, 3b, 4a, 4b and 4c were modified by replacing the surfactants with non-ionic surfactants of the type consisting of ethoxylated nonylphenols, ethoxylated dinonylphenols, ethoxylated linear alcohols, ethoxylated dodecyl- phenols, ethoxylated octylphenols, alkanolamides, ethoxylated alkanolamides, ethylene oxide-propylene oxide copolymers, ethoxylated propoxylated nonylphenols, and ethoxylated, propoxylated linear alcohols.

Example 5

Solid urban waste, hereinafter referred to as SUW, accumulated in reception halls before being separated and treated, is deodorized and disinfected by spraying it with a solution as in examples Ia, 2a, 3a and 4a at concentrations of 0.5-2.0% by means of a nebulisation system using 1-3 1 of solution per m ³ of waste.

Example 6

The SUW, sieved and ground, is conveyed to the composting hall where it is treated by spraying it at the exit points of the conveyor belts with

a solution as in examples Ia, 2a, 3a and 4a at concentrations of 0.5- 2.0% by means of a nebulisation system using 1-3 1 of solution per m ³ of waste. This treatment deodorizes the materials and activates the oxidative processes, supplying oxygen that facilitates fermentation, thus reducing the maturation time of the compost. The same type of treatment can be repeated on compost heaps if necessary and to deodorize and disinfect the halls.

Example 7

The superficial organic materials present in the biofilters, when sprayed by means of nebulisation with a solution as in examples Ia, 2a, 3a and 4a at a concentration of 0.5-2.0%, are deodorized and their oxidation is facilitated.

Example 8

The means of collection and transportation of SUW are deodorized and disinfected by means of washing with a solution as in examples Ia, 2a, 3a and 4a at a concentration of 0.05-1.5%.

Example 9

Particular compositions are used for washing waste bins by means of waste bin washers. To the mixtures as in examples Ia, 2a, 3a and 4a are added 100-400 g of surfactant already present in the compositions per 1 kg or 1 1 of solution. These compositions are used in amounts of 1- 2 kg or 1-2 1 per m ³ of water present in the tank of the waste bin washer (generally 5-6 m ³ ). These mixtures, in addition to deodorizing and disinfecting the waste bins, exert a better washing action on the surfaces, facilitating the removal of solid or semisolid materials attached thereto.

Example 10

The compositions as in examples Ia, 2a, 3a and 4a, dissolved in washing water in amounts of 1-2 kg or 1-2 1 per m ³ of the machines used for washing and cleaning streets or areas in which food markets operate, particularly fish markets that emit very bad odours, rapidly deodorize, wash and disinfect the areas treated.

Example 11

The accumulation of SUW in dumps or waste tips unfortunately remains one of the most widespread systems for waste disposal with a major environmental impact owing to the bad odour they emit in fermentation, which is even more marked in the percolate collecting on the impermeable base of the dump. The compositions as in examples Ia, 2a, 3a and 4a at concentrations of 0.05-1.5% are used to spray the layers of SUW in an amount of 1-2 1 per m ³ of material by means of a system to be inserted in the compactors that compress the various layers. These compositions eliminate the bad odours and activate the aerobic attack processes on the organic materials present. In addition, the oxidising power of the mixtures favours the oxidation of toxic metals which, on going over to higher oxidisation states, are more easily subject to hydrolysis and can therefore precipitate more easily and remain adhering to the solid phase of the waste, thus reducing their concentration in the percolate.

Treatment of the percolate with the compositions as in examples Ia, 2a and 3a by direct dissolving therein at concentrations of 0.5-5% deodorizes and clarifies the water, inhibits the anaerobic fermentation processes with reduction of toxic gases, favours the processes of oxidation of the organic materials present and of toxic metals that can precipitate more rapidly at controlled pH and be separated more easily.

Example 12

Increasingly widespread is the differentiated collection of waste due to the need to increase the recycling of materials and thus reduce the amount of discarded material. Conservation of the organic components present in all waste of domestic origin, the food industry, canteens and restaurants is a major problem, bearing in mind that they cannot be collected daily for reasons of cost. The compositions as in examples Ia, 2a, 3a and 4a at concentrations of 0.05-1.5% used to spray organic materials of any origin by means of simple nebulisers deodorize and sanitize them, thus allowing their conservation for more than ten days. The treatment must be applied at each new addition of organic material to the mass already conserved and, if necessary, can be repeated several times.

Example 13

The treatment modalities described in example 12 are also used to deodorize and disinfect animal residues produced by the meat processing industry, by slaughter-houses and butcher's shops, allowing problem-free conservation even for prolonged periods. In addition, the compositions can be used to wash, deodorize and disinfect the rooms of slaughter-houses and, in industries that process animal residues, can also be applied to animal residues in storage depots for processing and for the deodorising, washing and disinfection of the structures of the plant. For deodorizing and disinfecting the washing and effluent waters of slaughter-houses and plant treating animal residues, the compositions as in examples Ia, 2a, and 3a are used by direct dissolving therein at concentrations of 0.5-5%, which deodorize and clarify the waters and inhibit the anaerobic fermentation processes with reduction of toxic gases.

Example 14

The compositions as in examples Ia, 2a, 3a and 4a at concentrations of 0.05-2.0% are used for deodorizing, washing and disinfecting the stables and stalls of breeding farms for pigs, sheep, cattle, and horses and for the structures present in poultry breeding facilities using washing systems already existing in such structures. In the case of pig- breeding farms, the compositions must be added directly to the recycling waters from the primary excreta settling tanks. This system is used in plants to reduce the volumes of water to be used but also so as not to substantially increase the volumes of material to be stored in the collection tanks for the maturation of the excreta. The compositions which, through the washing waters, come into contact with the excreta facilitate their maturation, inhibit the growth of anaerobic bacteria and promote the oxidation of the foul-smelling and toxic gases present, including ammonia, the oxidation of which to nitrates is activated by the peroxides.

Example 15

The compositions as in examples Ib, 2b and 3c, in which the pH of the respective solutions is neutral, are preferably used at concentrations of 0.05-2.0% for household use for the deodorizing, washing and disinfection of delicate surfaces that may be attacked by a distinctly acidic pH, such as delicate floors, non-steel metal surfaces, baths or pet litters. The solutions are prepared directly in the nebulising canisters by pouring in the required amount of the compositions that are then dissolved or diluted by means of the addition of water up to a given value. In that way, the solution is already in the nebuliser and ready for use for spraying the surfaces to be treated. The compositions, on the other hand, are added direct to the amount of water needed for washing floors prior to use according to the scheduled dosages..

Example 16

The treatment modalities reported in example 15 are preferably used for the deodorizing, washing and disinfection of refrigerator cells and food storage depots emitting particularly strong odours such as those of meat and fish.