EP0368956A4

EP0368956A4 - Quaternary ammonium dithiocarbamate compounds

Info

Publication number: EP0368956A4
Application number: EP19890905248
Authority: EP
Inventors: Fred E. Woodward
Original assignee: National Starch and Chemical Corp
Current assignee: Ingredion Inc
Priority date: 1988-04-25
Filing date: 1989-04-13
Publication date: 1990-09-26
Also published as: AU3544289A; WO1989010956A1; EP0368956A1

Abstract

Quaternary ammonium dithiocarbamate compounds having formula (I) or (II) and methods of preparing same by mixing in water a quaternary ammonium compound having formula (III) and a dithiocarbamate salt having formula (i) or a bis-dithiocarbamate salt as represented by formula (ii) and recovering the resulting quaternary ammonium dithiocarbamate compound from the organic layer formed thereby. Compositions employing such compounds are primarily useful as surfactants and biocides.

Description

QUATERNARY AMMONIUM DITHIOCARBAMATE COMPOUNDS

Brief Statement of the Invention

The present invention relates to novel surfactant compounds and more specifically it relates to novel intermolecular quaternary ammonium dithiocarbamate compounds having particularly valuable surfactant properties, as well as other properties and advantages providing applications to a wide variety of commercial areas. Background of the Invention

Dithiocarbamates, particularly certain quaternary ammonium dithiocarbamate compounds, are known microbicidal agents useful in industrial applications and recently in plant protection. For example, one particularly valuable microbicidal product that has been on the market for many years is a combination of equal parts by weight of sodium dimethyldithiocarbamate and disodium ethylene bis-dithiocarbamate (30%, by weight, total active ingredients). This material is used in many industries for controlling the growth of bacteria, yeast and fungi, such as those found in industrial recirculating water cooling towers, air washers, evaporative condensers, pulp and paper mills, drilling fluids, secondary and tertiary petroleum recovery, cane and beet sugar mills, and the like. This compound has also been used for controlling the growth of algae in some of these applications.

However, well-known dithiocarbamate compounds, such as disodium ethylene bis-dithiocarbamate or sodium dimethyl- dithiocarbamate, have no surface active properties. These compounds are not wetting or spreading agents, are insoluble in oil or hydrocarbons, and are incapable of emulsifying water or solubilizing waterinsoluble organic compounds. These compounds are dried with considerable difficulty, and are characterized by a noxious odor.

Some quaternary ammonium dithiocarbamate compounds are disclosed in the literature. See, for example, U.S. Patent 4,006,251, and K. C. Kennard and D. M. Burness, "Dithiocarbamates. i. Quaternary Ammonium Dithiocarbamates", in J. Orcr. Chem.. 2±: 464-469 (April 1959). U.S. Patents 2,729,644 and 2,729,645 by H. Klopping et al disclose dithiocarbamate inner salts having the positively-charged nitrogen and negatively charged sulphur molecules in the same molecular entity. The quaternary salts of Patent 2,729,666 disclose only a chlorine or bromine atom as the negatively charged entity. U.S. Patents 3,621,048; 3,956,479; 4,007,281. 4,038,303; 4,082,756 and 4,097,600 disclose a number of quaternary compounds having the dithiocarbamate moiety in the quaternary portion of the molecule. See, also, East German patent application DD245,361, which published May 6, 1987.

There remains a continuing need for improved surface active and microbicidal compounds for a variety of industrial uses. Summary of the Invention

As one aspect of the present invention, a family of novel surfactant compounds are characterized by the general formula I or II:

where

R₁ and R₂ are the same or different and are selected from the group consisting of alkyl groups containing from 1 to 23 carbon atoms, optionally interrupted by one or more of the groups

where R₅ is H or CH₃ and n is 1 to about 75, and R₆ and R₇ are the same or different and are selected from the group consisting of alkyl containing from 1 to 10 carbon atoms, hydroxyethyl, hydroxypropyl, or benzyl;

R₃ is R₁, B₂ or R₄; R₄ is the residue from a quaternizing agent selected from the group consisting of a benzyl or C₁ to C₁₀ alkyl halide or a dimethyl or diethyl sulfate; or where R₁₇ R₃, R₆ and R₇ together form a cyclic moiety containing from 3 to 5 carbon atoms, optionally interrupted by 1 or 2 atoms selected from O or N; and optionally substituted by one or more alkyl groups containing 1 to 6 carbon atoms;

R₈ and R₉ are the same or different and are selected from the group consisting of an alkyl group and containing from 1 to 4 carbon atoms; and

A is an alkylene chain containing from 2 to 10 carbon atoms.

Another aspect of the present invention provides a method for preparing the novel compounds described above. The steps of this method include mixing, in a solvent or fluidizing liquid, a quaternary ammonium compound having the formula

where R₁, R₂, R₃ and R₄ are as defined above and X is an appropriate anion, with an alkali metal dithiocarbamate salt having the formula

or where R₈, R₉ and A are as defined above and M is a cation.

A chemical reaction occurs upon mixture and produces a largely organic rich phase containing most of the product and a largely aqueous phase containing most of the salt MX. The preparation is continued by separating the phases and recovering the organic phase containing the novel quaternary ammonium dithiocarbamate.

Still another aspect of the invention includes compositions employing the novel compounds of the invention containing as the active ingredient one or more of the novel compounds of the present invention, as surfactants, microbiocides, e.g., fungicides, algacides. bactericides, and lubricity additives, fuel oil additives, emulsifiers, and wood and paper preservatives.

Other aspects and advantages of the present invention will be further disclosed by the detailed description below, which contains specific examples. Detailed Description of the Invention

Novel quaternary ammonium alkyl dithiocarbamate salts are described which are characterized by surfactant properties, including surface and interfacial tension lowering and emulsification. These compounds may also be useful as antimicrobial agents, lubricity additives, wood preservatives, household cleaners and metal deactivators, or active ingredients in such compositions.

The Compounds

These novel compounds are characterized by formula I or II:

or

where

R₁ and R₂ are the same or different and are selected from the group consisting of alkyl groups containing from 1 to

23 carbon atoms, optionally interrupted by one or more of the groups

R₃ is R₁, R₂ or R₄;

R₄ is the residue from a quaternizing agent selected from the group consisting of a benzyl or C₁ to C₁₀ alkyl halide or a dimethyl or diethyl sulfate; or where R₁, R₃, R₆ and R₇ together form a cyclic moiety containing from 3 to 5 carbon atoms, optionally interrupted by 1 or 2 atoms selected from O or N; and optionally substituted by one or more alkyl groups containing 1 to 6 carbon atoms;

R₈ and R₉ are the same or different and are selected from the group consisting of an alkyl containing from 1 to 4 carbon atoms; and A is an alkylene chain containing from 2 to 10 carbon atoms. The maximum number of quaternary ammonium moieties present in each molecule of compound according to the present invention is four. One exemplary class of compounds according to the present invention are quaternary ammonium diethyldithio-carbamates, i.e., where R₈ and R₉ in formula I above are ethyl groups. Specific examples of this class are C₁₂ - C₁₆ alkyl dimethyl- benzyl ammonium diethyldithiocarbamate, dioctyldimethyl ammonium diethyldithiocarbamate, and didecyldimethyl ammonium diethyldithiocarbamate. Another exemplary class of compounds are quaternary ammonium ethylene bisdithiocarbamates, characterized by formula II, in which A is an ethylene group. A specific example of this latter class is alkyl dimethylbenzyl diammonium ethylene bisdithiocarbamate.

Method of Preparation of the Compounds In the preparative method for these novel compounds, a quaternary ammonium compound of formula

in a solvent or other appropriate fluidizing liquid is mixed with a dithiocarbamate salt. Quaternary ammonium compound reactants employed in the present method may desirably contain at least one methyl group and preferably at least two methyl groups, i.e. where one or two of R₁ through R₄ on the ammonium nitrogen atom are methyl. Other desirable R groups are benzyl, or alkyl groups containing from 1 to 18 carbon atoms, preferably from about 8 to about 18 carbon atoms. The source of the latter long-chain alkyl group will often be a mixture of fatty compounds, and this substituent will be designated by a range of carbon atoms for the chain, for example C₁₀-C₁₅, or C₁₂-C₁₈. There may also be on the carbon atoms of the hydrocarbon groups, certain substituents that do not interfere with the reaction. For example, a substituent on the quaternary ammonium nitrogen may be a fatty amido, or fatty ester group, or it may include an ether chain from alkylene oxide groups. Suitable aryl R groups are phenyl, lower alkyl-substituted benzyl and/or halogenated benzyl.

Desired quaternary ammonium compounds for use in this preparative method may be formed by quaternizing any tertiary amine by conventional means with convenient quaternizing agents. Alternatively, ethylene and propylene oxide conveniently convert primary and secondary amines to tertiary amines, which may be quaternized.

Desirable commercially available tertiary amines for quaternization include the octyl, decyl, dodecyl, C₁₄, C₁₆ and C₁₈ alkyl dimethyl amines, mixtures thereof and dioctyl and didecyl methyl amines [Ethyl Corp]. Other commercially available materials for forming the quaternary ammonium compounds are coco (C₈C₁₀C₁₂C₁₄ mixtures) dimethyl and dihydroxyethyl (RN(CH₂CH₂OH)₂ and C₁₄, C₁₆,C₁₈ dimethyl and dihydroxy ethyl and dihydroxypropyl amines [AKZO Chemie and Sherex]. These are available from a series of natural fats and oils and contain most of the unsaturation (double bonds) present in the original oil. Similarly the higher (C₁₄-C₁₈) dialkyl monomethyl and the monohydroxyethyl) amines are in many instances commercially available.

Imidazolines and their corresponding quaternary derivatives can also be employed to make a desired quaternary ammonium compound from a variety of alkyl carboxylic acids, and are represented by the formula:

where R₁ is the alkyl of a carboxylic acid of 1 to 21 carbon atoms; R₂ is hydroxyethyl, hydroxy propyl, or the residue from a higher alkylepoxide, R₃ is the residue from a quaternizing agent including benzyl, methyl, butyl, decyl and X is a halide or sulfate ion.

Amino amides are another important class of amines which are readily quatemized and conveniently converted by the process described below to dithiocarbamate salts of the present invention. They can be represented by the formula:

where R₁ is as above and R₂ is R₁ or the residue from a different carboxylic acid. Alkylation by an epoxide or by an alkyl halide or sulfate followed by quaternization provides a quaternary ammonium compound for use in this invention for conversion to a new surface active dithiocarbamate compound. The imidazoline and amino amide functions are frequently produced in the same molecule. Amides of dimethylaminopropyl amine are an important raw material from which quaternary ammonium dithiocarbamates can also be readily made. These compounds have the formula:

where R₁ and R₃ are as above, R₄ and R₅ are each the same or a different R₃. Thus tallow fatty acid reacted dimethylamino propyl amine, quaternized with benzylchloride and reacted with dimethyldithiocarbamate is particularly useful as an emulsifier. Trialkyl amines with 12 to 30 carbon atoms in which all 3 alkyls are essentially equal are an important group of compounds which, when quaternized and reacted with a dithiocarbamate according to this invention make products with unusual solubility and surface active properties. Such quaternary ammonium cations are commercially available, e.g., tetrabutyl ammonium, tributylmethylammonium [Ethyl], tricaprylmethyl ammonium and triC₈-₁₀ alkyl methyl [Henkel].

The alkylpyridines and pyridine are another important source of tertiary amines for quaternary ammonium compounds useful in this invention. One preferred source are the still residues from the production (from acetaldehyde and ammonia) of aldehyde collidine or 2-methyl-5-ethylpyridine and similar products which are crude mixtures of alkylpolypyridines [Lonza]. These are conveniently quaternized with benzylchloride. According to this invention their dithiocarbamate salts are extremely insoluble and make excellent corrosion inhibitors. They typically contain from 2 to 4 pyridine residues in each molecule.

Another group of multifunctional quaternary ammonium dithiocarbamates are based on the amines resulting from successive cyanoethylation and reduction of alkylamines. Particularly preferred is

where R is C₁₈ from tallow.

Polyether amines are another useful source of tertiary amines from which to make preferred products of this invention and are represented by the structure:

where X is O, N or S and where X is N, n is 2 ; R₁ is an alkyl of 1 to 22 carbon atoms or alkylaryl of 6 to 24 carbon atoms, and R₂ is H or CH₃. Such amines also include

where n is 1.5 to 15 and can be readily made from the commercially avaialable primary amines [Texaco Corp.] by methylating with methyl chloride plus an equal (molar) amount of sodium hydroxide. Other ether amines and ether diamines include C₈ to C₂₀ alcohol derivatives [Jetco] having the formula:

Another amine which forms a desirable quaternary ammonium compound of the invention is represented by:

where R₁ is poly (2 or more) functional polyol and n is equal to the number of hydroxyl groups. These amines which do not contain a hydrocarbon hydrophobe are also commercially available [Texaco's Jeffamines].

Another amine which can be quaternized and reacted with a dithiocarbamate according to the invention resulting in metal working lubricating agents is represented by:

where R₂ is H or CH₃, R₇ is an alkyl of 2 to 6 carbon atoms, and is commerically available [e.g., Quadrol, BASF].

Convenient quaternizing agents useful for converting the tertiary amines cited above to quaternary ammonium compounds are: methyl, ethyl, butyl and benzyl chloride, dimethyl and diethyl sulfate; and other agents well known in the art. Most useful are methyl chloride, dimethyl sulfate and benzyl chloride. Thus the X in the quaternary ammonium compound is preferably Cl-' but may also be any other appropriate anion, such as an anion of a mineral acid, e.g., Br-, SO₄ ^-2 and the like.

The dithiocarbamate reactant of the present inventive method is a dithiocarbamate salt, as represented by the formula

or a bis-dithiocarbamate salt as represented by the formula

Desirably, on the dithiocarbamate nitrogen atom of formula (i) R₈ and R₉, are hydrogen or short chain alkyl groups containing from 1 to about 4 carbon atoms. For example, R₈ and R₉ may be H and CH₃, H and C₂H₅, CH₃ and CH₃, or C₂H₅ and C₂H₅, respectively. Preferably, in the bis-dithiocarbamate salt of formula (ii), A is -CH₂-CH₂-. In the various dithiocarbamate salts, M is preferably an alkali metal cation, such as sodium, potassium, lithium or calcium. However, M may be another appropriate cation, such as NH₄+, alkyl ammonium or the like.

The compounds of the present invention when produced according to the described method do not rely on a simple mixing of two components. Rather, the reaction of the components causes a concentrated end product containing reduced salt content.

The reaction takes place under ambient temperature conditions with no significant exotherm so that neither heating nor cooling is required. This does not exclude either lowered temperatures, as down to about 10 C, or elevated temperatures, as up to about 40 C. Agitation is required during the reaction, and conventional stirring or mixing means may be employed. The reaction medium is a solvent or fluidizing liquid which will permit easy and efficient mixing of the reactants. The reaction medium may therefore be the solvents in which the reactants are prepared, i.e. generally water for the dithiocarbamate reactant, and water and a lower alcohol for the quaternary ammonium reactant. Depending on the solubility characteristics of the particular reactants and product chosen, larger amounts of alcohols or other organic liquids may be used in the reaction than are used to conventionally prepare the individual reactants, to effect the most desirable distribution of solutes in the two liquid phases produced, and the complete solution of any solute. The preparation of the products of this invention is done most easily by mixing approximate stoichiometric amounts of a quaternary ammonium sulfate or chloride with metal alkyl dithiocarbamate in such a manner that at least 50% of the alkali metal sulfate or chloride salt separates as a separate phase. Preferably at least 75% of the salt is removed by this method. However, the proportions of reactants employed in the preparative method for the compounds of the invention may vary appreciably from the stoichiometric ratios. It is advantageous to use either the dithiocarbamate or the quaternary ammonium compound in excess of stoichiometry to ensure sufficient distribution of the dithiocarbamate salt to the largely organic phase. A typical excess of dithiocarbamate over quaternary reactant, or vice versa, is 20%. The concentration of the reactants in the form in which they are charged to the reaction medium may vary widely. It is generally most convenient to use the reactants at the concentrations at which they are manufactured. The quaternary ammonium halides are generally prepared at 50-80% active concentrations. Alkali salts of dithiocarbamic acids are usually prepared at 20-50% active concentration. Dry forms of both reactants may also be used. The ratio of the reactants to water may also vary from about 10:90 to about 90:10, e.g. less than the amount of water present in the standard dithiocarbamate sodium salts.

As the result of the reaction according to the method, two phases are formed - a largely organic phase, containing the desired quaternary ammonium dithiocarbamate compound, and a largely aqueous phase containing the by-product salt. In some cases, the aqueous phase may contain water-soluble impurities associated with one or both of the reactants. Upon standing, these phases separate into two distinct layers, and the organic-rich layer containing the desired product is recovered. The aqueous layer is discarded.

If necessary, where separation does not occur rapidly or completely in a spontaneous fashion, phase separation can be assisted by the addition of extra salt to the aqueous phase and/or the addition of an organic solvent appropriate to the compound being made and compatible with its intended end use. After separation, the organic layer may be used as is, or diluted, or concentrated.

The novel compounds of the present invention may be made in situ where the reaction medium is an industrial water desired to be treated with biocide compositions of the invention. In this case, the reactants may be fed at concentrations as low as less than 5 ppm and the reaction occurs in situ to form the biocide compositions of the invention at ordinary levels of use. At such high dilution, phase separation does not occur, and solubility limits are never exceeded. The novel compounds in the organic layer after separation can also be carefully dried to a low water content. One such novel compound is tricaprylylmethyl ammonium dimethyldithiocarbamate, where R₁=CH₃, and R₂, R₃ and R₄ are each CH₃(CH₂)₇-, prepared according to the general method described in Example 1. Such dried or low water compounds of the present invention are particularly useful in fuels and other hydrocarbon solutions. The novel compounds of the invention may also be washed with water while in the organic-rich phase. The water separates rapidly out of this phase, leaving the novel compound with a particularly low chloride or sulfate content, which is desirable in a number of the uses for these compounds.

A product of this invention may also be produced desirably in a form free from inorganic salts by using a calcium dithiocarbamate salt to react with a quaternary ammonium sulfate or methosulfate. An appropriate calcium dithiocarbamate salt is conveniently prepared by mixing under appropriate conditions of temperature and pressure 1 mole of, dimethylamine (or another selected amine), 1 mole of carbon disulfide, and 1/2 mole of calcium hydroxide ("slaked lime"). Generally lime is precharged to enough water to produce a final product concentration of about 25-35%. Alternately or simultaneously, the dimethylamine and carbon disulfide are then added from pressurized load cell feed tanks. When the pressure drops, the reaction is complete. The product has a pH of about 11-12 and the lime, which is originally present as a slurry, is all dissolved and reacted.

The resulting calcium dithiocarbamate may be reacted according to the invention using either a quaternary ammonium sulfate or metho sulfate. The calcium sulfate formed by the reaction of the dithiocarbamate salt with a quaternary ammonium sulfate is essentially insoluble in water and can thus be removed by filtration of either the total reaction mixture or the organic-rich layer after removal of the water layer.

Uses of the Compounds All of the compounds of the present invention may be employed as surfactants for a variety of uses based on their surface active behavior at the appropriate dilutions. The surface active properties of compounds of the present invention also make them desirable as additives for de-emulsifiers for crude oils, thickeners for high water fluids, and in substances which aid in the flotation of heavy metal ores. When used as surfactants, the inorganic salts (NaCl, KCl, Na₂SO₄, etc) which are the usual by-product from their preparation need not be removed. These products are characterized by a different solubility in water than that of their parent anion and cation. In the preparation stage, this results in the major benefit of the separation of a concentrated sodium chloride or sulfate solution, leaving a conveniently marketable solution of concentrated product. As surfactants, these compounds in general do not form micelles and are insoluble in water to a concentration of about less than 0.005% by weight. In the presence of an excess of the quaternary ammonium compound used in preparation, the novel compounds will form a "clear" solution. These novel surfactant compounds may also be employed in combination with other conventional surface active materials.

Many of these compounds can be formulated into novel compositions for microbicidal use, e.g., to control the growth of bacteria, fungi and yeasts. Compounds generally described by the foregoing formulas are effective against microorganisms, such as Pseudomonas sp I., Ps. aeruginosa, Staph. aureus, E. coli, and against fungi, such as Candida tropicalis, Penicillium, and Aspergillus niger. Of the compounds represented by the general formula I or II given above, those compounds in which R₁ is methyl, R₂ is methyl, R₃ is octyl or decyl, R₄ is octyl or decyl, R₈ is ethyl and R₉ is ethyl are particularly effective against certain bacteria. A mixture of dioctyl or didecyl dimethyl ammonium salts is presently preferred for maximum anti-bacterial effect e.g. see Table I, example 9. Of the compounds represented by the general formulas I or II provided hereinbefore, the compounds particularly effective against fungi are those in which R₁ and R₂ are methyl, R₃ and R₄ are C₆-C₁₉ alkyl, and R₅ and R₆ are ethyl e.g. see Table I, example 18.

These compounds may also be used for their anti-bacterial action as "in-can" preservatives to keep a product from degrading while in a container, e.g. paint.

These microbicidal compounds may also be used in cold sterilization of surgical and dental instruments in hospital sterilization processes.

When used as microbiocidal agents against bacteria or fungi, compounds of the instant invention may be applied directly to the surface to be protected or may be dissolved in a pharmaceutical carrier. Typically, an effective amount, e.g. 0.1 to about 80% by weight of the compound, is included in an inert carrier and optionally a dispersing or surface active agent. Alternatively, an effective amount, e.g. 0.1 to about 60% by weight, may be incorporated into a solid carrier which may be inert, such as talc, clay, diatomaceous earth, flour, and the like. The novel compounds of the invention having microbiocidal function are desirably used in industrial water treatment where the concentration thereof can be as low as 1-5 ppm.

As the active ingredient or ingredients of these compositions, one or more of the novel compounds is present in any conventional formulation at an end use concentration which may vary within wide limits. Generally, the quantity of each novel dithiocarbamate compound should not be less than 1 ppm, nor for practical purposes exceed 100 ppm. The effective amount or concentration of the active ingredient used will vary according to the specific formulations and depending on its intended use.

Of course, when the compounds of the present invention are prepared and sold by manufacturers to end use customers, the novel compounds are desirably in higher concentrated form, e.g. 1% of compound. It is within the skill of the particular art for the end user to make dilutions appropriate to the desired end use. For example, household cleaners generally will have a much lower concentration of compounds in the end use product than would compositions for wood preservation.

These compositions may contain additional conventional components, such as suitable carriers, solvents, and surface active materials depending on the use to which the composition is directed. Additionally, the compositions may contain other conventional active ingredients or disinfecting agents in the desired formulation. Conventional solvents such as water ethanol, acetone, n-propyl alcohol, and/or isopropyl alcohol may be employed in the composition. Similarly, conventional surface active materials may be added to the composition. Optional additional known disinfecting ingredients such as formaldehyde, other known dithiocarbamate compounds or derivatives, or glyoxal may form part of the biocidal composition. These additional ingredients are added to the composition in a manner and to an extent familiar to those of skill in the art.

The advantages of the compositions of the invention reside in their reduced toxicity to humans, high effectiveness against a wide variety of microorganisms, compatibility with known disinfectant reagents and chemical stability for purposes of storage.

These compositions of the present invention may also be employed in other areas, e.g. in water treatment, in oil drilling or recovery operations, in fuel, cutting fluids and others. Compounds of the present invention are also useful in hard surface cleaners. For this use, a high concentration of a biocidal compound of this invention of about 1% to about 20% is preferred. A formula for such a hard surface cleaning compound may be readily compounded by one of skill in the art using conventional ingredients in addition to a compound of the present invention.

The compounds of the present invention also have a variety of uses in household products. For example, when added to water at high dilution these compounds can kill mildew and thus are applicable for use in cleansing products. Additionally, compounds of the present invention are compatible with non-ionic cleaning compounds additives over a wide range. For example, such products may contain from 5% nonionic surfactant with 95% of a compound of the present invention through the range of 95% of nonionic surfactant to 5% of a compound of the present invention. Such mixtures may be formulated to contain from 0.1% to about 20% biocidal compound, 10% to about 95% water, and the balance being surfactants and other inert materials. A presently preferred range for a use in cleansers is about 75% to 25% nonionic with about 25% to 75% of a compound of the present invention. Similarly, the compounds may be used in non-cleaning household products such as fabric softeners because of their anti-static action.

An additional use for compounds of the present invention are in preserving wood against infestation of insects, larvae, parasites and nematodes, algae and fungi. Compounds of the present invention would prevent wood rot. They would not leech out of the wood as do certain conventional wood preservatives, because the compounds of the present invention are soluble in oils and hydrocarbons. For the preservation of wood, it is desirable to have a quaternary ammonium dithiocarbamate compound of the present invention which is readily dilutable in water as well as a compound of the present invention which can be soluble in a hydrocarbon solution for impregnation into wood. For example, an effective wood preservative treatment would be to impregnate wood with a compound according to the present invention at 10 ppm per weight of wood. A desirable concentration range for such use is from .1% to 2% with a prefered concentration of .5%. The compounds are also useful for spraying onto wood chip piles to be used for making paper to prevent deterioration or incorporation into wax emulsion for coating wood. Similarly, the application of a compound of the present invention to wood could be used in finished lumber for above ground use and in treating wood for use below ground. Similarly, such compounds may be used in the paper industry for treating dilute pulp suspensions or white water to prevent the growth of "slime" at dilutions of up to 1 ppm. The concentrations of the products of this invention in the composition to be added to the paper machine may range from 1% to about 50%.

Another use for compositions of the present invention are as additives to distillate and residual fuels. These compounds may prevent static generation in the fuel and simultaneously provide anti-microbial action at the water-fuel interface as well as corrosion inhibition. They are particularly adaptable for this use because they dissolve in hydrocarbon. These effects make them particularly interesting as additives to jet fuels.

Yet another use for these compounds is as extreme pressure (E.P.) additives in lubricating oils. Such a composition containing a compound of the invention is particularly useful to reduce friction at the tool metal interface, in the cutting, machining and deforming of metals. In such compositions, compounds of the present invention would replace chlorinated paraffin and sulfur compounds which have been noted respectively to be carcinogenic or insufficiently active. Compounds of this invention may also be incorporated in synthetic, semisynthetic, or emulsion-type grinding, stamping, rolling and drawing fluids and in lubricating compounds containing no oil because of their water soluble and surfactant properties. The compounds may be added to semi-synthetic cutting or grinding fluids which contain a minor amount of oil. In cutting and grinding fluids the compounds are particularly desirable as additives because of their emulsifying ability and extreme pressure, lubricity and anti-microbial qualities. Additionally, these compounds do not cause skin irritation as do other E.P. additives.

Particularly interesting for corrosion inhibition purposes in the production and processing of oil are compositions containing pyridine quaternary ammonium dithiocarbamates.

Compounds of the invention may also be used to control bacterial growth in water flooding in secondary oil recovery processes. The compounds for use in this process may inhibit the iron sulfide and dithiocarbamate formation and precipitation in the injection water. Such reduced reactivity with soluble iron makes this use valuble. For example, compounds such as Table I, example 7 may be used for such a use at a concentration of 1-5 ppm. Similarly, these compounds are additionally useful in the flotation of heavy metal ores in mineral beneficiation. Such compounds display selective absorption with certain ores and make the surface hydrophobic, allowing them to be separated by froth flotation. The following examples are provided for illustration only and are not intended to limit the scope of the invention in any way. The following components of some of the novel compounds of the invention are referred to in the examples below by their trademarks as follows: 1) Adogen 432 is a commercially available average di-C₁₅ alkyldimethyl ammonium chloride sold by Sherex Corp.; 2) Sunthene 410 is a 100 sec. deep refined naphthenic mineral oil sold by Sun Oil Company; 3) PB750 describes a benzyl quaternized polyalkyl pyridinium chloride sold by Lonza; 4) Volnopol NM is sodium dimethyldithiocarbamate sold by Alco Chemical; 5) Varisoft LT is dioleylamidoethyl dihydroxyethyl ammonium sulfate sold by Sherex. 6) Varisoft 3690 is a 75% methyl-1-oleyl amidoethyl 2-oleyl imidazolinium methyl sulfate sold by Sherex Corp; 7) Igepal CO-630 is a nonylphenol with 9 E.O. sold by GAF; 8) Yarmol 302 is a pine oil sold commercially by Hercules Corp.; 9) BTC-851 is a 50% active alkyl (50% C₁₄, 40% C₁₂, 10% C₁₆) dimethylbenzyl ammonium chloride from Onyx Corp.; 10) Aliquat 336 PTC is 90% active tricaprylyl methyl ammonium chloride from Henkel Corp. Example 1. Novel quaternary ammonium dithiocarbamates. To a 500 ml flask equipped with a stirrer are charged: 0.334 equivalents (150 g.) of 80% by weight ethanol-water solution of alkyl (50% C₁₄, 40% C₁₂ and 10% C₁₀) dimethylbenzyl ammonium chloride and 0.35 equivalents (240 g.) 25% by weight aqueous solution of sodium diethyl dithiocarbamate. The mixture is stirred at ambient temperature for one hour. The mixture is allowed to separate in a separatory funnel for 16 hours. The bottom layer of water and salt (203 g.) is removed and discarded. The remaining organic phase (187 g.) is alkyl (50% C₁₄, 40% C₁₂, 10% C₁₀) dimethylbenzyl ammonium diethyldithiocarbamate (85% active). The product has a slight haze which clears on standing. The procedure described above may be employed to produce other novel compounds of the invention. For example, Table I below lists the R₁ - R₄ and R₇, R₈ groups for several novel quaternary ammonium dithiocarbamates produced by this method. Example 2. Novel Compounds with Microbicidal Activity

Products of the foregoing Example 1 and the following Table I (made in a like manner) were tested for microbicidal activity in controlling the growth of bacteria, fungi and algae. In the following Tables I-VI the concentration of biocidal composition stated as ppm is defined as the ppm of the separated organic layer, which is approximately 70% in the novel quaternary ammonium dithiocarbamates.

A. The compounds of Table 1, examples 1, 2, 5, 6 and 7 were tested for minimum inhibitory concentrations

(MIC) according to standard procedures described by the American Petroleum Institute "Recommended Practice for Biological Analysis of Subsurface Injection Waters" (API RP 38 Third Edition December 1975; Reissued March 1982) which is incorporated herein by reference. The novel compounds were tested against various organisms as listed below. The minimum concentrations in parts per million required to inhibit growth of these organisms by the novel compounds of the invention are set forth in Table II.

B. The compounds of Table I examples 5 and 6 were subjected to time-kill tests to determine effectiveness in terms of concentration of biocide (ppm) with time (hours). The target microorganism was Pseudomonas aeruginosa. Test tubes containing 10 ml of tryptic soy broth were dosed with the following levels of the compounds of Table I examples 5 and 6: 0, 50, 100, 200, 400, 600 and 1,000 ppm. Replicates were made of each dose so that quantitative measurements could be made at each time point (2, 4, , 8, 10 and 24 hours). After biocide addition, the tubes were inoculated with the microorganism. The bacterial count per ml at time zero was 2 × 10⁶/ml. Plate counts of all doses were made at each time point. The results for the compound of Example 5 are shown in the upper portion of Table III and for the compound of Example 6 in the lower portion of Table III.

C. The compound of Table 1 example 6 was subjected to time-kill tests against Desulfovibrio desulfuricans (Mid-Continent Strain 4). A pure culture of the microorganism was grown in API RP 38 standard broth. Sufficient amounts of the biocide were added to 9.5 ml glass vials so that desired biocide concentrations were achieved when the vials were filled. The culture used to fill each vial measured about 10⁶ colony forming units (cfu)/ml at time zero. Replicates of each level were made so that quantitative measurements of D. desulfuricans could be made at 2, 4, 6, 8, 10 and 24 hours. Parts per million levels of biocide were 5, 10, 15 and 20. Each level was done in duplicate. At each time point, levels of D. desulfuricans were measured semi-quantitatively using modified API agar deeps. The results showing bacterial count over time are shown in Table IV. D. The compounds of Table I examples 7 and 8 and compositions employing Table I example 1 according to the invention and several "controls" were tested for MIC as described in Example 2(A) against eleven microorganisms. The effectiveness of their biocidal MICS is reported in Table V.

E. Compounds of Table I examples 9 through 23 were tested for minimum inhibitory concentration as described in Example against four microorganisms. The effective concentrations for their biocidal activity are reported in Table VI below.

The novel quaternary ammonium dithiocarbamate compounds of the present invention may be used in a variety of microbicidal or anti-bacterial compositions.

TABLE VI

Pseudomonas Desulfovibrio Candida

Example aeruginosa desulfuricans tropicalis Chlorella sp

9 25 - 50 0 - 10 0 - 25 0 - 25

10 50 - 100 0 - 10 0 - 25 0 - 25

11 50 - 100 0 - 10 0 - 25 0 - 25

12 25 - 50 0 - 10 50 -100 0 - 25

13 100 - 250 0 - 10 50 -100 0 - 25

14 100 - 250 0 - 10 25 - 50 0 - 25

15 25 - 50 0 - 10 >1000 0 - 25

16 25 - 50 0 - 10 50 -100 0 - 25

17 25 - 50 0 - 10 0 - 25 0 - 25

18 25 - 50 0 - 10 0 - 25 0 - 25

19 100 - 250 0 - 10 25 - 50 0 - 25

20 25 - 50 0 - 10 100 -250 0 - 25

21 250 - 500 0 - 10 100 -250 0 - 25

22 500 -1000 0 - 10 0 - 25 0 - 25

23 >1000 30 - 40 >1000 0 - 25 Example 3. Surfactant and Emulsifying Compositions

A. To a solution of 56.8 grams dihydrogenated tallow-dimethyl-ammonium chloride (0.1 mole) in 20.9 grams water and ethanol warmed to 45 C was added 70.1 grams (0.1 mole) of a 4% solution of diethyldithiocarbamate. An opaque slightly viscous mixture resulted. An additional 12 grams of the dithiocarbamate was added and the solution stirred for one-half hour and allowed to separate. The solution was chilled to solidify the product. The liquid aqueous layer was removed, leaving 88.7 grams of dihydrogenated tallow dimethyl dithiocarbamate containing some alchohol and water.

B. An oil soluble emulsifier was prepared by mixing 246.0 grams (0.322 equivalents) Adogen 432, 69% active in water, with 225.0 grams (0.322 equivalents) of a 24.4% solution of sodium diethyldithiocarbamate in water and allowing the mixture to separate overnight. A lower layer of salt solution was separated and discarded leaving 262.3 grams of a solution of the product.

A dry test at 72 C for 14 hours showed 75.6% non-volatiles, or 198 grams of product. A 10% solution of this product in Sunthene 410 was clear, and readily formed emulsions from 3% to 50% in water. The addition of 5% of the diethanolamine salt of tallow fatty acids to the oil solution gave an equally clear oil soluble concentrate which formed stable emulsions in water and which had superior load carrying (anti-wear) lubricant properties. C. A mixture of 200 grams (active basis) of

Adogen 432 and 10 grams of sodium diethyldithiocarbamate formed a clear solution showing that the excess quaternary ammonium chloride was an effective solubilizing agent for the water and insoluble dithiocarbamate ion pair.

D. A novel compound of the present invention, dialkyl (C₁₅) dimethyl ammonium diethyl dithiocarbamate formed an emulsifiable concentrate for, e.g. addition to cutting fluids, lubricants and for other corrosion inhibiting uses, after dilution in 10 to 40 parts water. The composition was prepared by mixing to form a clear solution: 74% by weight Sunthene 410, 13% by weight of a emulsifier containing tallow amine plus 2 moles ethylene oxide, and 13% by weight of the Adogen 432 salt of diethyldithiocarbamate (68% active). E. The sodium dimethyldithiocarbamate salt may be converted to a surface action agent (emulsifier) by converting it into the salt of

where R₁ is the alkyl of oleic acid. To prepare this product of the invention, 1 mole (888 g.) of Sherex's Varisoft LT was mixed with good stirring with 1 mole, (358 g.) of a 40% solution of sodium dimethyldithiocarbamate [Alco Chemical].

After allowing the mixture to separate for 16 hours, there resulted an aqueous solution of NaCl and an organic rich layer comprising the new surface active quaternary ammonium dithiocarbamate. The product, dioleylamidoethyl dihydroxyethyl ammonium dimethyl dithiocarbamate, was soluble in Sunthene 410, whereas the Varisoft LT and the sodium dimethyldithiocarbamate are both insoluble in Sunthene 410. F. Solubilities in water and wetting and spreading properties of some other products of this invention were evaluated. Dioctyldimethylammonium dimethyldithiocarbamate 80% in water formed a clear concentrate. This compound is insoluble in water down to 0.0006%. Water is soluble in it up to 20%. When the compound is present at a concentration of 25% in water, it foams. At 0.1% in water it wets and spreads on a surface with a free energy of 50 dynes.

A formulation of 18.5% (11.3 g.) of this salt (9.0g, 100% basis) in 33.9 g. of water is completely insoluble in the water phase. The addition of 3.6% (3.5 g. of a 50% solution) of dodecyl trimethylammonium chloride gave a completely clear solution.

Hydrocarbon solutions were prepared of the following compounds. Dioctyldimethylammonium dimethyldithiocarbamate was 80% active and soluble at 3% in mineral spirits with a faint haze.

Tricaprylmethylammonium dimethyldithiocarbamate was 100% active and soluble at 1 to 99% in mineral spirits with no haze.

G. Another compound of this invention, decyloxypropyl bis 2-hydroxyethylmethyl ammonium dimethyldithiocarbamate, is prepared by reacting 49.3 g. of 75% active decyloxypropyl bis-2-hydroxyethylmethyl ammonium chloride [Tomah Q-14-2] with 35.75 g. of 40% active sodium dimethyldithiocarbamate. The mixture was clear and had low viscosity. It was diluted stepwise and observed at each successive dilution. It remained clear down to 0.14% active product salt, but was hazy at 0.08% active. Thus this product is soluble at concentrations above its critical micelle concentration and insoluble below its CMC.

Example 4. Novel Compounds for Corrosion Inhibition and Fuel Additives A variety of these compounds may also be used as additives to petroleum fuels to increase the efficiency thereof, provide anti-static action and aid in the inhibition of corrosion and rust. These compounds may be substituted for presently used compounds in so-called detergent fuels and other petroleum products.

These compounds may also be employed in cooling towers to stabilize the chloride in the water and inhibit corrosion of the towers. Additionally, compounds according to this invention may be used as additives to cutting fluids to assist in the lubrication of the tool face; and in water flooding uses to avoid the formation of bacterial slime by Desulfovibrio desulfuricans and to inhibit the precipitation of iron and carbon.

A. For example, to prepare a highly water insoluble compound according to the invention, which has corrosion inhibition and metal deactivation properties, 55 grams of a solution of PB750 was stirred with 55 grams of a 40% solution of sodium dimethyldithiocarbamate, and allowed to separate to give 105 ml of inorganic rich layer. The alkyl pyridines are the by-products residues from the production of aldehyde collidine. The compound formed is extremely insoluble in water, much less than 10ppm.

B. In a similar manner the insoluble salt of ethylene bis-dithiocarbamate anion with PB750 was prepared. It is insoluble in toluene, isopropanol, and water. It can be emulsified or solubilized in an excess of nonionic surfactant only with difficulty.

C. For example, as oil soluble quaternary ammonium dimethyldithiocarbamates may be prepared as follows:

49.1 g of Aliquat 336 PTC (Oil mole) was mixed with 35.89 g of a 40% solution of sodium dimethyldithiocarbamate (Oil mole), and stirred vigorously for 15 minutes. The mixture separated to two phases rapidly when stirring stopped. 100 ml of water was added and stirring continued for 15 minutes. The mixture was allowed to stand overnight, after which it was placed at -5°C until the water phase had frozen. The product phase which was a viscous oil and contained about 9% water was poured off. It was dried at 40-50°C by stirring in an air stream for 2 hours, at which point it contained 2.8% water. It did not disperse in water, and was soluble in mineral oil. In a similar manner oil soluble quaternary ammonium dialkyl dithiocarbamate salts were prepared from tri-n-butyl methyl ammonium chloride, and tetra-n-butyl ammonium chloride. Example 5. Novel Compounds as Cleansers and Other Household Uses

Other uses for these novel compounds are in household laundry detergents and other cleaners, where the individual compound has an acceptable odor and is compatible with the other components of the detergent.

For use in pine oil cleaner-sanitizers, the compounds of the invention exhibit a compatible emulsification and synergy with the components of pine oil.

A. The novel product, didecyldimethyl ethylene bis diammonium dithiocarbamate is completely insoluble in either hydrocarbon or water. However, in a formulation with mineral spirits, tallow amine plus 5 moles of ethylene oxide and sodium alkane (C₁₃ average) sulfonate it forms a clear microemulsion suitable for sale as a hard surface cleaner with antimicrobial properties.

A similar emulsion prepared from 30 pts d-limonene, 30 pts alkyl (50% C₁₄, 40% C₁₂, 10% C₁₆) dimethyl benzyl diethyl, dithiocarbamate (80% in water), 30 pts nonylphenol and 9 moles of ethylene oxide, 40 pts water, and 20 pts dipropylene glycol methyl ether forms a thin, essentially clear microemulsion readily dilutable into water, and is an effective hard surface cleaner with germicidal properties when diluted 1:64 in water. B. For example, a formulation suitable as a rinse cycle softener was prepared from 5 parts of the Adogen 432 dimethyldithiocarbamate salt [Sherex] 1 to 5 parts of a nonionic surfactant and 90 to 94 parts water.

C. Another example is the compound methyl 1-oleylamidoethyl 2-oleyl imidazolinium dimethyldithiocarbamate. To prepare this compound, 96.4 g. of Varisoft 3690, (0.1 mole) was mixed with 35.75 of 40% sodium dimethyldithiocarbamate (0.1 moles) and 100 g. of water. The cloudy mixture was intimately mixed and allowed to stand overnight. 35 g. of water containing the sodium methosulfate separated. The remaining product is 31% active. This product when solubilized with from 0.2 to 1 parts of a nonionic surfactant on the weight of the active product makes an effective rinse cycle softener and biocidal agent for home laundry applications.

D. The composition described in the preceding Example 1 was also shown to be a superior emulsifier for a pine oil cleaner formulation compared to the corresponding chloride salt normally used in such formulations. Thus the formula: 8.05% Igepal CO-630, 7.95% Pine Oil (Yarmor 302), 8.00% isopropanol, 4.95% Antimicrobial (either Onyx BTC-851 or a novel compound of the invention) and 70.05% water were combined according to conventional methods. The emulsion using Onyx BTC-851 as the antimicrobial was unstable. Using the corresponding dimethyldithiocarbamate salt as the antimicrobial gave a transparent, stable micro-emulsion. The latter salt was prepared according to the method of Example 1 from 35% g. of Onyx's BTC-851 and 180 g.

Volnopol NM (40% active) giving 283.5 g of an organic rich layer and 262.3 g of a water layer with 8.8 g. water rinse containing about 29 g. of NaCl. Example 6. Novel Compounds Useful as Metal Working Fluids

A. A composition suitable for use as a metal working fluid may be prepared using as a lubricating ingredient compounds of the present invention. For example, such a compound may consist of 0.1 to 10% of one or more of the compounds of claim 1, in which R₁ has at least 12 carbon atoms; 2 to 90% mineral oil, 5 to 50% of a supplemental emulsifier, such as petroleum sulfonates, rosin and tall oil soaps, and phosphate esters of nonionic surfactants, 0 to 20% ethoxylated fatty amines, and 0 to 80% water. This composition is suitable for dilution at 1:5 to 1:100 in water for application to a metal surface being cut, machine ground, or deformed.

B. A concentrated fluid suitable for dilution at 1:5 to 1:100 for use as a lubricant for the cutting, grinding, machining, and drawing of metal may be prepared from the following: 0.1 to 10% one or more of the compounds of this invention having lubricating properties, 0 to 90% of a nonionic surfactant, 0 to 20% of an anionic surfactant, and 0 to 10% of an ethoxylated amine. The concentration of the two surfactants and the amine equals at least the concentration of the novel compound. This composition on dilution preferably has a pH of over 7.5 and is a clear solution.

The above-noted uses as well as a variety of other uses may be expected for the compounds of the present invention based on their characteristics of antibacterial and fungal action, corro-sion inhibiting action, pleasant odor, emulsifying ability, anti-static action, compatability with other substances, stability, efficiency, low activation temperature, and thickening ability.

Numerous modifications of the compositions and methods of the present invention may be obvious to those of skill in the art upon review of the teachings of this specification. For example, as will clearly be understood by one of skill in the art, the compounds of this invention may be included in a variety of formulations depending on the specific use desired. Additionally, these compounds may be sold at varying concentrations by a manufacturer, generally at high concentrations. The concentrations may be further diluted by intermediate sellers or end users. Such varied concentrations and formulations, the preparation of which is within the skill of the art, and other modifications are believed to be encompassed by the scope of the appended claims.

Claims

What is claimed is: 1. A compound having the formula

where:

R₁, and R₂ are the same or different and are selected from the group consisting of alkyl groups containing from 1 to 23 carbon atoms, optionally interrupted by one or more of the groups

where R₅ is H or CH₃ and n is 1 to about 75, and R₆ and R₇ are the same or different and are selected from the group consisting of alkyl containing from 1 to 10 carbon atoms, hydroxyethyl, hydroxypropyl, or benzyl; R₃ is R₁, R₂ or R₄; R₄ is the residue from a quaternizing agent selected from the group consisting of a benzyl or C₁ to C₆ alkyl halide or dimethyl or diethyl sulfate; or R.₁, R₃, R₆ and R₇ together form a cyclic moiety containing from 3 to 5 carbon atoms, optionally interrupted by 1 or 2 atoms selected from O or N; and optionally substituted by one or more alkyl groups containing 1 to 6 carbon atoms;

R₈ and R, are the same or different and are selected from the group consisting of an alkyl group containing from 1 to 4 carbon atoms; and

A is an alkylene chain containing from 2 to 10 carbon atoms.

2. The compound according to claim 1 having the formula

I and wherein R₈ and R₉ are each ethyl or each methyl.

3. The compound according to claim 1 having the formula

II and wherein A is -CH₂ -CH₂-.

4. The compound according to claim 1, wherein R₃ and R₄ are each octyl, each decyl or both.

5. The compound according to claim 4, which is dioctyldidecyl ammonium diethyldithiocarbamate.

6. The compound according to claim 1 wherein R₄ is benzyl, R₃ is a mixed C₁₂ to C₁₆ alkyl and R₁ and R₂ are each methyl.

7. The compound according to claim 6 which is benzyl alkyl (C₁₄, C₁₂) ammonium diethyldithiocarbamate.

8. A microbiocidal composition comprising at least one compound according to claim 1 in an amount effective to limit or kill growth of microorganisms.

9. A water supply for use in industrial or oilfield operations containing about 1 to about 100 ppm of at least one compound according to claim 1.

10. A laundry cleanser containing an effective amount of one or more of the compounds according to claim 1 to provide microbiocidal, surface active and antistatic action thereto.

11. A cleaning compound comprising from about 0.1% to about 20% of one or more of the compounds of claim 1 in solution with a surfactant selected from the group consisting of nonionic, anionic, cationic or amphoteric surfactants; and one or more optional soluble builder salts.

12. A cleaning compound according to claim 11 further comprising pine oil in a microemulsion form and an optional amount of isopropanol.

13. A composition suitable for use as a hydrocarbon fuel additive comprising one or more of the compounds according to claim 1 in an amount effective to provide anti-microbial properties thereto.

14. A compound according to claim l dissolved in a hydrocarbon and essentially free from water suitable for addition to a fuel.

15. A hydrocarbon fuel containing from about 5ppm to about 0.1% of a compound according to claim 1 capable of preventing microorganism growth at the fuel-water interface.

16. A composition suitable for use as a synthetic or semi-synthetic cutting fluid additive comprising one or more of the compounds of claim 1 which are soluble therein, in an amount effective to impart extreme pressure lubricity and anti-microbial properties thereto.

17. A synthetic, semi-synthetic, or soluble oil cutting or grinding fluid containing: (a) one or more of the compounds of claim 1 in an amount sufficient to provide extreme pressure lubrication when the fluid is diluted 1:1 to 1:100 in water, (b) from 0 to about 90% water, (c) one or more surfactants selected from the group consisting of nonionic, cationic, or anionic surfactants; (d) an optional amount of mineral oil and (e) an optional rust inhibitor.

18. Wood impregnated with a compound according to claim 1 in an amount effective to inhibit destruction thereof by insects, fungus, and other microorganisms.

19. A method of preparing novel quaternary ammonium compounds which comprises the steps of: mixing, in a solvent a quaternary ammonium compound having the formula:

where R₅ is H or CH₃ and n is 1 to about 75, and R₆ and R₇ are the same or different and are selected from the group consisting of alkyl containing from 1 to 10 carbon atoms, hydroxyethyl, hydroxypropyl, or benzyl; R₃ is R₁, R₂ or R₄;

R₄ is the residue from a quaternizing agent selected from the group consisting of a benzyl or C₁ to C₁₀ alkyl halide or a dimethyl or diethyl sulfate; or where R₁ , R₃, R₆ and R₇ together form a cyclic moiety containing from 3 to 5 carbon atoms, optionally interrupted by 1 or 2 atoms selected from O or N; and optionally substituted by one or more alkyl groups containing 1 to 6 carbon atoms; X is an anion; with a dithiocarbamate salt having the formula or a bis-dithiocarbamate salt as represented by the formula

where R₈ and R₉ are the same or different and are selected from the group consisting of an alkyl containing from 1 to 4 carbon atoms; and A is an alkylene chain containing from 2 to 10 carbon atoms; and recovering from the -resulting organic-rich phase a quarternary ammonium dithiocarbamate compound of claim 1.

20. A method for controlling microbial growth in water supplies for industrial or oil field operations comprising adding to said water at least one compound according to claim 1 in an effective microbicidal concentration of between about 1 to about 100 ppm.