MX2008006920A - Process for making an ionic liquid comprising ion actives - Google Patents

Abstract

A process for making ionic liquids containing ion actives, which provide fabric treating benefits, surface treating benefits and/or air treating benefits. The ionic liquid is made from an ion active feedstock and an ionic liquid forming counterion feedstock, which preferably comprises another ion active.

Description

PROCESS FOR ELABORATING AN IONIC LIQUID THAT COMPRISES ACTIVE IONS FIELD OF THE INVENTION The present invention relates to processes for preparing ionic liquids containing active ions, which provide benefits for the treatment of fabrics, benefits for the treatment of surfaces or benefits for the treatment of air. The ionic liquid is made from raw material of active ions and a raw material of counterions forming ionic liquids, which preferably comprises another active ion.

BACKGROUND OF THE INVENTION In recent years, ionic liquids have been exhaustively evaluated as ecological or "green" alternatives to conventional organic solvents with respect to a wide range of synthetic organic applications. Ionic liquids offer some unique characteristics that distinguish them from other conventional organic solvents, such as ineffective vapor pressure, a wide range of liquid, high polarity and charge density, hydrophobic or hydrophilic characteristics, and unique solvating properties.

In addition, the effectiveness of ionic liquids has been demonstrated in applications in which aqueous chemistry can be problematic (for example, applications involving proton transfer or nucleophilicity) or in applications in which coordination chemistry could damage substrates used. Recently, ionic liquids and ionic liquid combinations have been applied in consumer products (such as formulations for home care, air care, surface cleaning, laundry and fabric care), as well as in industrial products. Illustrative ionic liquid-containing consumer products are described in U.S. Pat. no. 2004 / 0077519A1. Furthermore, compositions containing ionic liquids composed of an active ion and an ionic liquid forming counter ion are described in US Patent Application Ser series no. 60 / 624,128. Some ingredients used in consumer products are provided by manufacturers in a highly concentrated form. In some cases, up to 70-90 of the weight percentage of the concentrate is constituted by the active ingredient. Concentrates can use organic solvents, such as isopropanol or ethanol, and sometimes a small amount (up to 10%) of water or surfactants can be used. In the process of producing consumer products, the active concentrates are diluted with water and, optionally, with alcohols. The resulting products are distributed to merchants or consumers. The characteristics of dispersibility and The viscosity of these active concentrates can present serious problems to those who process them. Surfactant active materials are available as aqueous dispersions only in relatively low concentrations. It is generally not possible to prepare these aqueous dispersions with more than about 30% of active materials without facing problems of difficult solution in terms of viscosity and stability during storage of the product. These problems are manifested as separation of phases or products that can not be poured, inadequate dispersion or deficient dissolution characteristics under normal conditions of use. It is desirable to take advantage of the various unique characteristics of the ionic liquid to cope with these problems. Conventionally, ionic liquids are prepared by mixing the raw material in chlorinated solvents, such as methylene chloride or carbon tetrachloride. In order to recover the ionic liquid, vacuum is applied to evaporate the chlorinated solvents. It is not practical to use this conventional process for production for various reasons. Vacuum evaporation is slow and consumes a lot of energy. Special measures must be used in order to satisfy the regulatory requirements for the handling of these solvents. It is difficult to remove traces of chlorinated solvents from the ionic liquid, so the resulting ionic liquids become inadequate for many consumer product applications. Therefore, it is desirable to apply a discontinuous process, or preferably, a continuous process to prepare active concentrates of ionic liquid in an aqueous carrier. It is also desirable that the continuous process elaborates the aqueous concentrates with a high active content. Specifically, it is desirable that the aqueous ionic liquid active concentrates have a suitable viscosity and dispersibility, so that the concentrates can be easily processed to become consumer products. In addition, it is desirable that the ionic liquid active concentrates have an appropriate phase or dispersion stability for transport and storage.

BRIEF DESCRIPTION OF THE INVENTION In one of its various aspects, the present invention relates to a continuous process for preparing an active ionic liquid. In one example of the invention, the process comprises the steps of: introducing a first reagent comprising an organic amine oxide and a second reagent comprising an organic sulfate or an organic sulfonate in the reaction zone of a reactor; Sufficient amount of a protic acid is introduced into the reaction zone, such that the resulting reaction mixture has a pH of less than about 5; the reagents and the protic acid are circulated in the reaction zone at a sufficient flow rate to achieve thorough mixing of the first and second reagents with the protic acid and thus produce a product stream comprising that ionic liquid is removed from the reaction zone that product stream comprising a cation ionic liquid of amine oxide and of organic sulfate anion or organic sulfonate, and is transferred the product stream to a separator, while controlling the introduction of the first and second reagents in the reaction zone and the removal of the product stream from the reaction zone, such that the residence time of the reaction in the reaction zone is sufficient to produce the ionic liquid; wherein the product stream is allowed to separate into an upper phase and a lower phase in that separator, and a product comprising the ionic liquid, in general, is recovered as the upper phase in the separator. In another aspect of the invention, the same process can be used to make ionic liquid active concentrates using betaine and an organic sulfate or an organic sulfonate as a raw material, wherein the step of protonation with an acid can be optional. Further aspects of the invention, such as the manufacture of the aforesaid concentrated ionic liquids based on surfactants without using solvents, are also discussed below. halogenated, as well as a new marketing method made possible by the present invention.

DETAILED DESCRIPTION OF THE INVENTION As used herein, "consumer product" refers to a material that a user (ie, a consumer) uses for their body, home (such as kitchen and bathroom surfaces, carpets, floors, windows, mirrors and tables), automobiles (such as interior, exterior, metal surfaces and windshields), other personal or household items (such as earthenware, fabrics, kitchenware, utensils in general, tableware and glassware), as well as the air that surrounds the user. The "composition of the consumer product" can also include the material used by institutional users (such as hotels, restaurants and offices) or by service providers (such as dry cleaners and cleaning and maintenance services). Consumer products, in this context, can encompass any product that contains a surfactant. As used herein, "industrial product" refers to a material used in the commercial process of manufacturing an article. Non-limiting examples include degreasing compositions of articles such as metals and compositions for textile treatments used in the textile processing or finishing of cloth articles, such as garments or curtains. Industrial products, in this context, can encompass any of these products that contain a surfactant.

As used herein, "for treatment", "treatment" refers to a composition or process for cleaning, renewing or maintaining the air or target surface. For example, "renew" includes the processes of removing the wrinkled or worn appearance of a cloth article or imparting a pleasant smell to a cloth item, air, a soft surface or a hard surface. Cleaning also covers aspects of personal care, such as bathing, washing hair and the like. As used herein, the terms "surface", "target surface" or "treated surface" refer to non-biological and inanimate surfaces, as well as biological surfaces, such as skin and hair. Non-limiting examples of such surfaces are found on soft surfaces, such as fabrics, cloth articles, fabrics, fibers, and hard surfaces such as tableware, kitchenware, utensils in general, glassware, tables, kitchen surfaces, surfaces of bathrooms, floors, windows, interiors and exteriors of automobiles, metals, and combinations thereof. As used herein, the term "active ion" means the ionic (cationic or anionic) form of an active capable of providing benefits, for example, a fabric treatment benefit, a surface treatment benefit or a benefit of air treatment, to a destination surface. The active ion retains the ability to provide such benefits. As used herein, the terms "active" and "benefit agent" are interchangeable.

As used herein, the term "active ionic liquid" means an ionic liquid composed of at least one active ion and at least one ionic liquid forming counterion. As used herein, the term "ionic liquid" refers to a salt having a melting temperature of about 100 ° C or less, or in an alternative embodiment, has a melting temperature of about 60 CC or less, or in yet another alternative embodiment, it has a melting temperature of about 40 ° C or less. In other embodiments, the ionic liquids do not have a discernible melting temperature (based on differential scanning calorimetry analysis), but have the "flowability" at a temperature of about 100 ° C or less, or in another embodiment , have the "flowability" at a temperature of about 20 to about 80 ° C, that is, the usual temperatures for washing fabrics or crockery. As used herein, the term "flowability" means that the ionic liquid has a viscosity of less than about 10,000 mPa.s at the temperatures specified above. In a manufacturing context, ionic liquids can be supplied with a pump. It is to be understood that the terms "ionic liquid", "ionic compounds" and "IL" (for its acronym in English) refer to ionic liquids, ionic liquid compounds and mixtures (or combinations) of ionic liquids. The ionic liquid may comprise an anionic IL component and a cationic IL component. When the ionic liquid is in liquid form, these components can associate freely with each other (that is, they are piled up). As used herein, the term "ionic liquid combination" refers to a mixture of two or more, preferably, at least three, different and charged IL components, wherein at least one IL component is cationic, and at least one component of IL is anionic. Accordingly, the combination of three anionic and cationic IL components in a mixture will produce at least two different ionic liquids. Combinations of ionic liquids can be prepared by mixing individual ionic liquids of different IL components or preparing them by means of combination chemistry. These combinations and their preparation are discussed in greater detail in U.S. Pat. num. 2004 / 0077519A1 and 2004 / 0097755A1. As used in this, the term "ionic liquid compound" refers to a mixture of a salt (which may be solid at room temperature) with a proton donor Z (which may be a liquid or a solid), as described in the aforementioned documents in the previous paragraph. When mixed, these components become a liquid at an approximate temperature of up to 100 ° C, and the mixture behaves like an ionic liquid. The active ion that forms the active ionic liquid is an ionic entity that provides the desired treatment benefit to a target object or to a target surface. For example, within the present context, fabric treatment generally refers to the cleaning, renewal or care of any textile material or product, which includes, but is not limited to, loose or free fibers, yarns (including filaments), woven textiles, non-woven textiles, knitted textiles, articles and the like. Cloth items include, but are not limited to, garments, components used in the manufacture of garments, carpets, upholstery and the like. In addition, such fabrics can be formed with any natural, artificial or synthetic material, or a combination thereof. Surface treatment generally refers to the cleaning, renewal or care of any solid surface material that is not cloth, including, but not limited to, crockery, utensils and any other element intended to be in contact with food, and surfaces hard, for example, floors, counters, appliances, sinks, bathtubs, toilets, mosaics and the like, as well as personal hygiene. Air treatment refers to the cleaning or renewal of ambient air, usually in a closed area. Examples of suitable active ions include, but are not limited to, the ion form as surfactants, bleaches, bleach activators, additives, antimicrobial agents, softeners, colorants, dye fixers, optical brighteners, as described in the application U.S. patent series no. 60 / 624,128. The ionic active can be anionic or cationic, as necessary for the desired benefit and, in general, it is derived from a salt or acid of a known benefit agent. For example, if a conventional benefit agent in the salt form corresponds to the formula X + Y ", and the anion Y" provides the desired treatment activity of the fabric, surface or air, then the anionic form of the agent is employed. of profit in the active ionic liquid. Examples of suitable anionic actives include, but are not limited to, anionic phosphate anionic surfactants, anionic alkyl sulfate or linear or branched sulphonate surfactants, anionic sulfate and alkylated sulphonate surfactants and linear or branched alkoxylates, perborate brighteners, percarbonate and aníónicos peracid, and the like. Alternatively, if the X + cation of the conventional benefit agent in the salt form of the formula X + Y provides the desired treatment activity of the fabric, surface or air, then the cationic form of the benefit agent in the active ionic liquid. Examples of suitable cationic actives include, but are not limited to, cationic quaternary ammonium antimicrobial agents, cationic quaternary ammonium fabric softeners, cationic quaternary ammonium surfactants and the like. Examples of suitable zwitterionic actives include, but are not limited to, amine oxide surfactants and betaine surfactants. In addition, a conventional nonionic or zwitterionic benefit agent can be converted to an ionic active by ionic funcionalization with a cationic functional group (such as a trimethylammonium alkyl group) or an anionic functional group (such as a sulfate group). Alternatively, a zwitterionic benefit agent can be ionized by changes in the pH of the compositions below the pKa of the zwitterionic active, resulting in a cationic form of the benefit agent.

Active ions Cationic active ions can be derived from the following reagents: (a) amine oxide rgent surfactants, including but not limited to those corresponding to the formula: wherein R3 is a C2-22 alkyl, C8-22 hydroxyalkyl, C8.22 alkylphenyl group and mixtures thereof; R4 is a C2-3 alkylene or a C2-3 hydroxyalkylene group, or mixtures thereof; x is from 0 to about 3; and each R5 is independently a C3-C3 alkyl or a C1-3 hydroxyalkyl group or a polyethylene oxide group containing an average of about 1 to about 3 ethylene oxide groups; or the R5 groups are linked together by an oxygen or nitrogen atom to form an annular structure; and (b) betaine rgent surfactants, including but not limited to those corresponding to the formula: R-N (+) (R1) 2-R2COO (-) wherein R is selected from the group consisting of C10-C22 alkyl, C10-C22 alkylaryl and C10-C22 arylalkyl, all of which may be optionally interrupted by amido or ether linkages; each R1 is a C1-C3 alkyl group; and R2 is an alkylene group of C1-C6. In one embodiment of the process of the present invention, the amine oxide reagents are protonated to form the cationic active ions in the resulting active ionic liquid. The resulting cationic active ion has the formula: wherein R3, R4 and R5 are as described above. In another embodiment, betaines can be used as reagents to form the cationic active ion in the resulting active ionic liquid. The resulting cationic active ion (protonated form) has the formula: R-N (+) (R1) 2-R2COOH wherein R, R1 and R2 are as described above. In the process of the present invention, the following organic sulfates or sulfonates are illustrative surfactant-type reactants which can be combined with the above amine oxide or betaine reagents to form an active ionic liquid. (1) alkylsulfate (AS), alkoxysulfates and alkyl alkoxysulfates, wherein the alkyl or alkoxy is linear, branched or mixtures thereof; moreover, the attachment of the sulfate group to the alkyl chain can be terminal in the alkyl (AS) chain, internal to the alkyl chain (SAS), ie, secondary, or mixtures thereof: the non-limiting examples include linear alkyl sulphates of C-? o-C2o that have the formula: CH3 (CH2) xCH2OS03"M + wherein x is an integer of at least 8, preferably, at least about 10; and M + can be H or alkali metal or alkaline earth metal cations. For example, reagents can understand Na +, K +, Mg ++ and the like; or linear secondary alkyl sulfates of C10-C2O having the formula: OS03-M + CH3 (CH2) x (CH) (CH2) and CH3 wherein x + y is an integer of at least 7, preferably, at least about 9; or y can be 0 and M + is H or alkali metal cations or alkaline earth metal. The reagents may comprise H +, Na +, K +, Mg ++ and the like; or C10-C20 secondary alkyl ethoxy sulfates having the formula: 0 (CH2CH20) 2S03-M 15 CH3 (CH2) x (CH) (CH2) and CH3 wherein x + y is an integer of at least 7, preferably, at least about 9; x or y can be 0; z is approximately 1.2 (Prom.) a about 30; and M + is H or an alkali metal or alkaline earth metal cation. For example, betaine salts may comprise Na +, K +, Mg ++ and the like; Non-limiting examples of alkoxy sulfate include sulfated derivatives of commercially available alkoxy copolymers, such as Pluronics® (ex BASF); (2) mono and diesters of sulfosuccinates: non-limiting examples include monoester saturated and unsaturated C12-? 8 sulfosuccinates, such as lauryl sulfosuccinate available as Mackanate LO-100® (from The Mclntyre Group); C6-C12 saturated and unsaturated diester sulfosuccinates, such as dioctylester sulfosuccinate 10 available as OT® aerosol (from Cytec Industires, Inc); (3) alkylaryl sulfonates, the non-limiting examples of which include tosylate, alkylaryl sulphonates having straight or branched, saturated or unsaturated C8-C- | 4 alkyls; alkylbenzene sulfonates (LAS), such as C-n-C-? 8 alkylbenzenesulfonates; and benzene sulfonates; (4) alkyl glycerol ether sulfonates having 8 to 22 carbon atoms in the alkyl entity; (5) branched half-chain alkyl sulfates (HSAS), branched chain-average alkylaryl sulfonates (MLAS) and branched half-chain polyoxyalkylene alkyl sulphates; Non-limiting examples of MLAS are described in U.S. Pat. num. 6,596,680; 6,593,285 and 6,202,303; (6) linear and branched sulphated and sulphonated fatty acids and oils, such as sulfates or sulfonates derived from soap, coconut oil and potassium available as Norfox 1101® from Norman, Fox & Co. and potassium oleate from Chemron Corp., as well as paraffin sulfonates; (7) fatty acid ester sulfonates having the formula:And the.

R CH (S03") C02R2 wherein Ri is straight or branched C8 to C-? 8 alkyl, and R2 is straight or branched Ci to C6 alkyl. For use herein, sulphates and organic sulfonates are preferred. Process The present invention encompasses, but is not limited to, a continuous process for making an active ionic liquid. The process is described in detail in relation to a specific modality of the continuous process, in which the active ionic liquid is composed of amine oxide and alkyl sulfate. However, it is understood that the process can be used to making other active ionic liquids composed of any combination of the active ions described above. Moreover, the exemplified continuous process of the present invention can be used to make other active ionic liquids composed, for example, by a cationic fabric softener, a cationic antimicrobial, or a cationic surfactant with an anionic bleach activator, or an anionic surfactant. . In one embodiment, the active ionic liquid is composed of quaternary ammonium cations and alkylsulfonate anions. Naturally, the process of making some active ionic liquid may not require the protonation step. A general embodiment of this aspect of the present invention includes the steps of continuously feeding an amine oxide and an alkyl sulfate into a reaction zone where deep mixing of the reactants occurs. The reactor can be a stirred tank reactor, a piston flow reactor with static mixers or a recirculating circuit reactor. A proton donor, such as sulfuric acid, can be fed directly into the reaction zone to protonate the amine oxide, and thus produce the active ionic liquid. A stream of product containing the active ionic liquid is removed from the reaction zone and fed into a phase separator. The active ionic liquid can be easily recovered from the upper layer of the phase separator. Once steady-state conditions have been established in the reactor, the rate of introduction of the reactants (amine oxide and alkyl sulfate) in the reaction zone to be approximately the same as the velocity to remove the product stream from the reaction zone, such that the residence time of the reaction mixture or the reactants in the reaction zone remain constant. Other variables in the reaction zone, such as temperature, agitation, and flow rate, preferably, also remain constant. In this embodiment, to achieve the active ionic liquid by the continuous process of the present invention, amine oxide and alkylsulfate are introduced into the continuous reactor in a molar ratio to satisfy the stoichiometry, generally a molar ratio of about 1. 1, or about 0.9: 1, or about 1.2: 1. The raw material of amine oxide and alkyl sulfate can be in the form of aqueous concentrates. A typical amine oxide feedstock can be an aqueous concentrate, possible to be pumped, having from about 20 to about 40% by weight of amine oxide. In one embodiment of the present invention, the raw material contains about 30% by weight of amine oxide in water (eg, C10-C2o dimethine oxide) of surfactant type and has a viscosity of about 150 mPa.s (150 centipoise). Illustrative amine oxide concentrates are commercially available from Stepan Lonza or Kao, under the trade names Ammonyx®, Barlox® and Amphitol®. A typical alkyl sulfate raw material may be an aqueous concentrate having about 20-70% by weight, preferably, about 30-60% by weight of alkylsulfate. In one embodiment of the present invention, the raw material contains about 50-70% by weight of alkyl sulfate in water and has a viscosity greater than about 500 mPa.s (500 centipoise). Illustrative alkyl sulfate concentrates are commercially available in Stepan or Kao, with the trade names Stepanol® or Emal®. In addition to water, the raw material can also comprise additional solvents, such as methanol, ethanol and other low alcohols (C3-C6), and those solvents (preferably non-halogenated) can be used to reduce the viscosity of the system. A proton donor is also introduced into the reaction mixture to protonate the amine oxide, and thus convert it into the amine oxide cation. Exemplary proton donors are protic acids, including, but not limited to, sulfuric acid, halogen-based acids (such as HF, HCl, HBr, Hl, HCl0), nitric acid, phosphoric acid, trifluoroacetic acid, or p-acid. -toluenesulfónico (PTSA). The amount of proton donor in the reaction mixture should be sufficient to maintain the reaction mixture at a pH of less than about 5, preferably from about 3 to about 5 and, more preferably, from about 3.5 to about 4. The continuous reactor, especially the reaction zone, is maintained above room temperature, preferably at a temperature of about 40 ° C to about 99 ° C, or about 50 ° C to about 85 ° C, so that the ionic liquid is in liquid form. The raw material of amine oxide and alkyl sulfate can be heated above room temperature, preferably at a temperature of about 50 ° C to about 70 ° C or at a temperature equal to that of the reactor. The preheating of raw materials reduces their viscosity to facilitate transfer to the reaction zone and minimizes the drop in temperature in the reaction zone. The raw materials can be preheated and the reactor heated by any known means, for example, by means of a heat exchanger. To achieve the desirable results of the invention in an optimal manner, the configuration of the reactor, the properties (such as the viscosity) of the reaction mixture and the volumetric fluid index can be such that a turbulent flow is maintained in the zone of reaction. In one embodiment, the reactor system operates at a Reynolds number of approximately 10,000. In other embodiments, the reactor system operates at a Reynolds number of at least about 2000, preferably from about 5000 to about 50,000, in the reaction zone. In one embodiment, the residence time (measured simply as input versus output over time, at steady state) of the reaction mixture in the reactor is from about 5 seconds to about 10 hours or from about 0.1 minutes to about 30 hours. minutes In another modality, the time of permanence of the reaction mixture in the reactor is from about 30 seconds to about 15 minutes. The residence time can also be determined by the time necessary for a marker (eg, a dye retarder or a radioactive tracer) to pass through a reactor. It will be appreciated that similar operational parameters may be used in discontinuous processes within the scope of the present invention, as described below. To recover the active ionic liquid resulting from the reaction stream, the reaction stream from the continuous reactor is removed and fed into a phase separator. The reaction stream is allowed to separate by interfacial tension or gravity. In a typical arrangement, the reaction stream is fed into the separator near its midpoint, and a separator is provided with two discharge tubes. The first discharge tube is attached to the separator at a location adjacent to or at the top of the separator. The second discharge tube is connected to a location at the bottom of the separator or near it, and extends upwardly along the outside of the separator to maintain the height of the lower layer of the separator at a desired level just below the place where the separator and the first discharge tube meet. The active ionic liquids are concentrated in a separate upper layer in the upper part of the lower aqueous layer, and the upper layer of the phase separator is removed through a discharge tube in a storage tank. The upper layer recovered from the separator may contain water and an additional solvent, as well as the active ionic liquid. In one embodiment, the top layer recovered contains from about 50 to about 100% by weight, or from about 60 to about 90% by weight of active ionic liquids. In another embodiment, the recovered top layer comprises from about 0 to about 35% by weight of water, or from about 10 to about 25% by weight of water. In another embodiment, the recovered top layer comprises from about 0 to about 15% by weight, or from about 5 to about 12% by weight of alcohol, for example, methanol or ethanol Representative representative ionic liquids are produced by this continuous process and they are recovered as the upper layer of the separator or the continuous reactor. They have the approximate properties detailed below.

Active IL (A) is composed of dodecyl dimethylamine oxide and Isalchem 123® sulphate, derivative of Isalchem 123® alcohol (available from Sasol Chemical Industries, Ltd, Johannesburg, South Africa) by means of sulfation processes known in the industry. The active ingredient (B) is composed of dodecyl dimethylamine oxide and Lial 123® sulphate, purified from Lial 123® alcohol (available from Sasol Chemical Industries, Ltd, Johannesburg, South Africa) by means of sulfation processes known in the industry. 1 All measurements are carried out in a differential scanning calorimetry system Perkm Elmer Pyps 1 The samples are heated from room temperature to 75 ° C at a rate of 10 ° C per minute, cooled to -50 ° C at a rate of 5 ° C per minute, they are kept at -50 ° C for 60 minutes, then heated to 75 ° C at a rate of 10 ° C per minute The end of the transition of the first order in the second heating trace is reported as the "melting temperature" complete "The start of the first order transition in the cooling trace is reported as "solidification start temperature" All measurements are made on a TA Instruments AR 1000 cone and plate viscometer. A stainless steel cone 40 mm in diameter, with an angle of 2 ° is used. All the dispensers are carried out under the following conditions. An increase rate of temperature of 5 ° C / m? n and a constant shear stress of 5 Pa The viscosity of the sample is reported from 30 to 80 ° C ND indicates that the sample was too viscous to obtain data under the conditions of the test The ionic liquid active concentrates prepared by the continuous process of the present invention provide a higher active content than the aqueous active concentrates currently available from the suppliers. Moreover, these ionic liquid active concentrates present a desirable viscosity profile in such a way that can easily be formulated as consumer products using standard processing equipment, so it is not necessary to use high temperatures or high-pressure pumps. In addition, these ionic liquid active concentrates have phase stability under normal storage and transport conditions. The foregoing discussion describes a preferred continuous process for the manufacture of concentrated ionic liquids based on surfactants, it should be understood that the process herein can also be carried out in discontinuous form Clearly, when considered in its broadest aspect, an important feature of the present process is that it can be carried out without halogenated hydrocarbons, such as those which, in general, are used in the manufacture of ionic liquid compositions. As those experienced in the industry will readily appreciate, avoiding the need to use and recover halogenated hydrocarbons in large-scale manufacturing processes greatly simplifies plant design and operation. Therefore, the present invention also encompasses: A process for preparing an ionic liquid comprising: a) preparing a reaction mixture by mixing a protonated amine oxide, a protonated betaine or mixtures of these, with an organic sulfate or an organic sulfonate or mixtures of these, in the presence of water or water-alcohol, but without halogenated hydrocarbon solvents, for a sufficient time to allow the formation of the ionic liquid; b) allowing the reaction mixture to separate into a higher phase and a lower phase by discontinuing the mixing; and c) retaining the upper phase comprising the ionic liquid. The various reaction conditions mentioned above can also be used in this more general process than the present invention allows. Moreover, it should be understood that the production of ionic liquids based on surfactants in the present manner allows new opportunities of cost reduction to manufacturers of products that contain one more surfactant component. In principle, a manufacturer of products containing surfactants would prefer, to distribute them in vastly disseminated regions, even globally, obtain the surfactant raw material from somewhere or more centralized locations and then use that surfactant raw material to formulate the product final for local distribution and sale. This centralized procurement would also allow the locally formulated finished product to be tailored to local needs, customs and practices. For example, the formulation of laundry detergents in regions with hard water may require auxiliary ingredients other than those formulated for regions with soft water, although the nature of the surfactants themselves may be the same in both cases. By employing a system of "local formulation with central supply", localized needs could be satisfied in a simple and economical way. The problem with this commercial plan is that surfactants usually exhibit complex phase behaviors, so that they must be transported as relatively dilute compositions. As a result, many of the transportation costs originate in the presence of water in the raw material of surfactants. Especially with respect to amine oxide surfactants, the removal of water from the surfactant raw material is not a minor issue. Due to its phase behavior, even the surfactant "pastes" Up to now, more concentrated aqueous products have only included approximately 30% - 40% by weight of surfactant (the CSP mainly comprises water) in order to keep it in a pump condition in the manufacturing plant. Various solvents can be added to decrease the viscosity of high concentrates, but at an added cost. Clearly, at concentrations of more than about 40%, by weight, in water, the amine oxide / water surfactant systems are essentially difficult under normal plant operating conditions. Moreover, it is inadvisable to attempt to reduce the viscosity of the amine oxide / water concentrate paste by heating, since the amine oxide can begin to decompose at temperatures as low as 100 ° C. As can be seen from the teachings contained herein, the present invention provides a higher concentrate (eg, with as little as 10% -30% by weight of water), although the surfactant raw material is still under pumping, which allows the opportunity to ensure considerable savings in transportation costs. Consequently, the aforementioned business plan now becomes viable. Therefore, the present invention also encompasses: A method for achieving cost reduction in the manufacture of products comprising one or more surfactant components; This method includes: a) determining at least one supply site for converting this one or more surfactant components into an ionic liquid based on surfactant; b) establishing one or more receiving sites away from the aforementioned supply site to receive shipments of the ionic liquid from that place of supply; c) transporting the ionic liquid from a place of supply to the aforementioned one or more reception places; and d.) employing that ionic liquid in such one or more receiving sites to manufacture said products. Particular attention should be paid to the ionic liquid of examples 1-5. As observed in the previous tables, ionic liquids prepared with dodecyl dimethylamine oxide and sulfated alcohol Isalchem 123® surprisingly have a preferred viscosity profile over ionic liquids prepared with sulfated alcohol Lial 123®. Without intending to be limited by theory, the hypothesis now is that this improvement in the viscosity profile may be due to the fact that Lial 123® is made from a raw material comprising only approximately 45%, by weight, of secondary alcohols, while Isalchem 123® alcohol raw material comprises approximately 95%, by weight, of secondary alcohol. Naturally, that results in 45% versus 95% by weight of secondary alkyl sulphates, respectively.

Accordingly, the present invention also encompasses, as a preferred embodiment, ionic liquids comprising an organic amine oxide entity (especially C12-C1 dimethylamine oxide) in combination with a sulphated alcohol entity derived from a secondary alcohol, and it comprises more than 45%, preferably, about 50% to about 100%, most preferably, at least about 95%, by weight, of sulfated secondary alcohol (especially secondary alcohol of C-? 2-C? 3). The ionic liquids may further comprise the low water or water-alcohol (especially ethanol) levels mentioned above. Such preferred ionic liquids have a desirable viscosity profile, as mentioned above, and are free of halogenated solvents. This recently recognized technical effect further supports the breadth of the aspect of the invention, namely: The use of an alkyl sulfate derivative of a secondary alcohol raw material; that raw material comprises more than 45%, by weight, of secondary alcohol substituents to prepare an ionic liquid having an improved viscosity profile (i.e., can be pumped) at temperatures of 80 ° C and below, preferably without using solvents of halogenated hydrocarbons. The relevant parts of all the cited documents are incorporated herein by reference; the mention of any document should not be construed as an admission that it constitutes a prior industry with respect to the present invention. In the degree to which Any meaning or definition of a term in this written document contradicts any meaning or definition of the term in a document incorporated by reference, the meaning or definition assigned to the term in this written document shall govern. Although particular embodiments of the present invention have been illustrated and described, it will be apparent to those skilled in the industry that various changes and modifications can be made without departing from the spirit and scope of the invention. It has been intended, therefore, to cover all the changes and modifications within the scope of the invention in the appended claims.

Claims (19)

NOVELTY OF THE INVENTION CLAIMS

1. A continuous process for preparing an ionic liquid having an amine oxide cation and an alkyl sulfate anion; the process comprises the steps of: introducing a first reagent comprising an organic amine oxide and a second reagent comprising an organic sulfate or an organic sulfonate, or mixtures thereof, in the reaction zone of a reactor; Sufficient amount of a protic acid is introduced into the reaction zone, such that the resulting reaction mixture has a pH of less than about 5; the first and second reagents and the protic acid are circulated in the reaction zone at a sufficient flow rate to achieve a thorough mixing of the first and second reagents with the protic acid and thus a product stream comprising the liquid is produced ionic; the product stream is removed from the reaction zone and the product stream is transferred to a separator, characterized in that the product stream comprises an ionic liquid which, in turn, comprises a cation of amine oxide and a sulfate anion organic or organic sulfonate, while controlling the introduction of the first and second reagents in the reaction zone and the removal of the product stream from the reaction zone, so that the residence time of the reaction mixture in the reaction zone is sufficient to produce the ionic liquid; Y the product stream is allowed to separate in an upper and lower phase, and the ionic liquid in the upper phase is recovered.

2. The process according to claim 1, further characterized in that the first reagent in the protonated form comprises an amine oxide cation having the following formula: wherein R3 is a C8.22 alkyl, a C8.22 hydroxyalkyl, or a C8.22 linear, branched alkylphenyl group, or a combination of linear and branched; R4 is a C2.3 alkylene or C2-3 hydroxyalkylene; x is from 0 to about 3; and each R5 is an alkyl of C -? - 3 or a hydroxyalkyl group of C1-3 or a group of polyethylene oxide containing an average of about 1 to about 3 ethylene oxide groups; optionally, the R5 groups may be linked together by an oxygen or nitrogen atom to form an annular structure, and wherein the second reactant is an organic sulfate or an organic sulfonate.

3. The process according to claim 1, further characterized in that the anion of the organic sulfate or the organic sulfonate is selected from the group consisting of: (1) alkyl sulfates, alkoxy sulfates and alkyl alkoxysulfates; (2) mono and diesters of sulfosuccinates; (3) alkylaryl sulfonates; (4) alkyl glycerol ether sulfonates; (5) branched, half-chain alkyl sulphates and branched, half-chain alkylaryl sulfonates; (6) oils and sulfated and sulphonated fatty acids; (7) fatty acid ester sulfonates; and (8) mixtures of these.

4. The process according to claim 3, further characterized in that the anion of the organic sulfate has the following formula: R1-S04" wherein R1 is an alkyl, a hydroxyalkyl or a linear, branched alkylphenyl or a combination of linear and branched.

5. The process according to claim 1, further characterized in that the circulation speed is sufficient to establish a Reynolds number of at least about 2000.

6. The process according to claim 1, further characterized in that the zone Reaction is heated above room temperature.

7. The process according to claim 1, further characterized in that the residence time of the reaction mixture in the reaction zone is from about 0.1 minute to about 30 minutes.

8. The process according to claim 1, further characterized in that the process optionally comprises adding an organic solvent to the reaction zone, so that the resulting reaction mixture has a viscosity of about 0.01 to about 0.07 Pa.s at 60 C.

9. The process according to claim 8, further characterized in that the organic solvent is selected from the group consisting of C1-C8, C2-C8 diols, C2-C8 glycols and mixtures thereof.

10. The process according to claim 1, further characterized in that the protic acid is selected from the group consisting of sulfuric acid, halogen-based acids, nitric acid, phosphoric acid, trifluoroacetic acid or p-toluenesulfonic acid, and mixtures of these .

11. The process according to claim 1, further characterized in that the pH of the reaction mixture ranges from about 2 to about 5.

12. The process according to claim 1, further characterized in that the ionic liquid of the phase separator. it comprises less than about 35% water.

13. The process according to claim 1, further characterized in that the molar ratio between the amine oxide and the alkyl sulfate is about 1: 1.

14. The process according to claim 1, further characterized in that the amine oxide and the alkylsulfate are preheated to a temperature of about 50 ° C to about 70 ° C.

15. A continuous process for preparing an ionic liquid by introducing and intermixing a first reagent comprising a betaine and a second reagent comprising an organic sulfate or an organic sulfonate, or mixtures of these in a reactor, and thus forming a reaction mixture, as well as continuously removing a portion of the reaction mixture from the reactor; wherein the total mass of the reactants introduced into the reactor is equal to the total mass of the reaction mixture removed from the reactor.

16. The process according to claim 15, further characterized in that the reaction mixture comprises an ionic liquid which, in turn, comprises a cation of betaine having the following formula: R-N (+) (R1) 2-R2COOH wherein R is selected from the group consisting of C10-C22 alkyl, C10-C22 alkylaryl and C10-C22 arylalkyl, all of which may be optionally interrupted by amido or ether linkages; each R1 is a C1-C3 alkyl group; and R2 is an alkyl group of C1-C6.

17. The process according to claim 15, further characterized in that the reaction mixture comprises an ionic liquid which, in turn, comprises an anion of organic sulfate or sulfonate. selected from the group comprising: (1) alkyl sulfates, alkoxy sulfates and alkyl alkoxysulfates; (2) mono and diesters of sulfosuccinates; (3) alkylaryl sulfonates; (4) alkyl glycerol ether sulfonates; (5) branched, half-chain alkyl sulphates and branched, half-chain alkylaryl sulfonates; (6) oils and sulfated and sulphonated fatty acids; (7) fatty acid ester sulfonates; and (8) mixtures of these.

18. A process for preparing an ionic liquid comprising: preparing a reaction mixture by mixing a protonated amine oxide, a protonated betaine or mixtures of these with an organic sulfate or an organic sulfonate or mixtures thereof in the presence of water or water-alcohol, characterized in that it is carried out for a sufficient time to allow the formation of the ionic liquid without halogenated hydrocarbon solvents.

19. An ionic liquid comprising an organic amine oxide entity in combination with a sulfated alcohol entity derived from an alcohol; the alcohol comprises more than 45% by weight of secondary alcohol substituents.