US2368560A - Method of preparing hydroxy heavy metal soap compositions - Google Patents

Description

Patented Jan. 30, 1945 METHOD OF PREPARING ROXY HEAVY METAL SOAP COMPOSITIONS Arthur Minich, Westfield, N. J.

No Drawing. Application May 1'7, 1944,.

Serial No. 536,022

3 Claims.

This invention relates to a method of preparing mixtures of hydroxy metal soaps in vehicles and while capable of use in the production of soaps of various metals, is especially useful in the preparation of hydroxy copper naphthenates alone or in combination with other metallic soaps including normal copper naphthenates. Thus it is possible to obtain, for example, hydroxy copper naphthenate soaps of practically any desired hydroxy content.

In my previous Patent No. 2,116,321, dated May 3, 1938, I described the preparation of hydroxy metal soaps including hydroxy copper naphthenate in such manner that the end product was generally in dry pulverulent form. This required, in the course of the incorporation of such hydroxy metal soaps into other compositions, mechanical grinding or other steps, so as 'to bring about proper dispersion of the hydroxy soap in the associated composition. This procedure is attendant with certain diificulties. It i well known that grinding of pulverulent matter is a laborious and relatively expensive operation and often requires special apparatus including dust collecting apparatus, etc. Furthermore, the production of the hydroxy metal soaps in pulverulent form requires drying equipment of relatively large floor area and the drying operation usually requires a protracted time cycle. Following the drying, the hydroxy metal soap has to be comminuted by such means as grinders,

sifters, etc. in order to yield a substantially uni-' form pulverulent material. In addition to these drawbacks, it is also necessary to select the raw material component carefully, so that the resultant composition is non-sticky, and will not tend to agglomerate. Moreover it is necessary that water remaining from the double decomposition reaction be substantially removed in order to permit the proper functioning of the end product. This has been accomplished by mechanical drying.

I have found that all of the above mentioned disadvantages accruing to the production and use of pulverulent hydroxy metal soaps, may be substantially eliminated through the employment of the present invention next to be described.

In carrying out the present invention in its preferred practical form, I employ three solutions A, B and C: Solution A representing an aqueous solution of an alkali soap of a predetermined organic water-insoluble acid, together with free and unreacted alkali hydroxide, and Solution B representing an aqeous solution of the watersoluble salt of the selected heavy metal. When these two solutions are brought together under agitation, there is formed the hydroxy metal soap of such metal and acid. This hydroxy metal soap precipitates out in the form of a water-insoluble magma. It is separated from the by-product salts and a large portion of the water by mechanical means, such as filter pressing. The magma may also receive subsequent water washings to free it entirely from the by-product salts.

It is also within the purview of this invention to eliminate at this stage of the method the removal of any of the water and/or the said byproduct salts.

Following this the magma is then mixed under agitation with Solution C which is preferably wholly or in part volatile. Ordinarily it is preferred to employ for this purpose a vehicle including a volatile solvent because this aids in the subsequent removal of water.

The vehicle employed may be selected from a broad range. For example, I have found it very satisfactory to employ as a vehicle a petroleum solvent, known under the trade name Sovasol. Likewise, I have satisfactorily employed coal tar hydrocarbons, e. g., xylol.

The solvent may be selected from the broad class of organic substantially water-insoluble liquids which are employed in the arts, generally, as solvents, such as paint solvents, rubber solvents, etc. They are not necessarily a solvent for the hydroxy metal soaps forming part of the magma to which I have referred.

The mixture of the hydroxy metal soap magma in said vehicle is thereupon subjected to the action of heat to effect a dehydration operation. This may be carried out at atmospheric pressure or in vacuo, and I have found that under these conditions, the water present in the hydroxy metal soap magma will distill off readily and completely, leaving behind the hydroxy metal soap in finely dispersed form in the vehicle.

It is necessary during the dehydration operation that there is continually present a part or all of the vehicle associated with the hydroxy metal soap so that, as the operation proceeds, the soap become thoroughly dispersed through-v out the vehicle. Aside from this critical factor, the actual amount of vehicle employed may vary within wide limits depending upon conditions. It has been found expedient in some cases to return continuously to the reaction apparatus those portions of the volatile vehiclewhich distill off with the water, so as to maintain within the reaction kettle substantially uniform conditions.

The material produced at the conclusion of the dehydration or drying step may contain different amounts of vehicle, so as to be in the form of a. relatively thick paste or in the form of a pourable liquid, depending upon what is desired for particlar uses, or if it comes from this operation in the form of a thick paste, it may be diluted with further amounts of the vehicle as it may be desired. In any event, the degree of dispersion attained by the procedure of this invention is superior to that which may be obtained by mechanically dispersing the pulverulent hydroxy metal soap in the same vehicle.

I have referred to the production of a soap of a single metal during double decomposition steps described. I may, however, if so desired effect double decomposition of a plurality of metals at the same time or, if desired, Imay carry out double decomposition as described for one metal and also the same steps in connection with one or more additional metals, and thereafter commingle or bring together the resulting magma of the several metals before jointly dehydrating them in the drying step which I have described.

I have also referred to the use of a waterinsoluble organic acid, in the production of the hydroxy metal soap according to this invention. I do not limit this invention to the use of a single acid alone, but may employ a plurality of such acids for this purpose. The acids employed are, however, substantially waterinsoluble and substantially non-volatile and should be such as to form the water-insoluble hydroxy metal soaps. They can be aromatic acids, such as para-chlorbenzoic acid, aliphatic acids, such as oleic acid, linseed oil fatty acids, and cyclic acids, such as naphthenic acid. Tall oil may also be used for this purpose.

The formation of the hydroxy metal soap in form of its water magma has been described as the initial process step of this invention. It is possible, however, to precipitate first either a hydroxy metal soap of greater basicity than is desired in the dehydrated product or it is also feasible to precipitate the straight hydroxide of the metal. In these cases, it is possible to include in the vehicle employed in drying, a sufficient amount of the organic acid to react with the metal hydroxide or hydroxy metal soap of the metal present, so as to bring about the desired hydroxy content of the dehydrated product.

The production of a wide variety of metal soaps may be accomplished by the method of this invention according to the metals which enter into the reaction. For example, I may use such metals as copper, zinc, lead, cobalt, manganese, iron and generally the other heavy metals which are capable of forming water-insoluble hydroxides.

For the purpose of concrete example, I shall now describe the production of a hydroxy copper naphthenate soap useful for various purposes, but more particularly as a fungicidal and insecticidal agent. This compound may also form a component part of orchard sprays for pest control.

EXAMPLE 1 Solution A droxy metal naphthenate in the vehicle.

Solution 8 Pound: Copper sulphate crystals (25% copper) 190 Water 70C Solutions A and B were commingled under agitation. The hydroxy copper naphthenate which was formed precipitated out in the form of a water-insoluble magma. The entire reaction mixture was then filter pressed to remove the larger portion of the water. The hydroxy metal soap magma remaining in the filter press was washed to remove the by-product salts. The hydroxy metal soap magma containing approximately 70% water was then incorporated under agitation into the following vehicle which may be referred to as:

Solution C Pounds Sovasol (a volatile petroleum distillate solvent manufactured by The Standard Oil Co. of New York) 200 The mixture of Solution C with the hydroxy metal naphthenate magma was heated under agitation in a closed kettle to a temperature of approximately C. The water was thus distilled off together with a portion of the volatile petroleum distillate solvent, a part of which solvent upon condensation was fed back into the kettle.

The foregoing example contained 259 lbs. less naphthenic acid than the normal compound would require. On a percentage basis, it contained 33% of the amount required to form the normal compound.

The dehydration of the hydroxy metal naphthenate soap during this dehydration step was so complete that upon completion, there was present less than 1% of water in the end product. The end product, in the approximate amount of 264 lbs., constituted a mobile mixture of the hy- The consistency was that of a heavy, but flowable liquid. The concentration of the hydroxy metal soap was 70% (metal content approximately 8%), the balance being the petroleum distillate solvent.

It was particularly notable that in the end product, the resulting mixture of the metallic soap was practically of colloidal fineness in dispersed form-in fact, much finer and complete than could possibly be obtained by mechanical means. This is an important factor because, generally speaking, the efliciency of many compositions, particularly fungicides, depends upon very fine state of dispersion.

It is to be noted that the end product is a true hydroxy copper naphthenate because it has been formed through the double decomposition of copper sulphate with the combination of alkali naphthenate soap and free alkali hydroxide. More specifically, inthe reaction referred to, there was present approximately pounds of free and unreacted aqueous sodium hydroxide solution of oi the acid to be employed in Solution A and the remainder in Solution C, the condition being in every case that the total amount 01' organic acid employed is insumcient to form the normal compound and therefore perforce the hydroxy compound must be formed. As exemplary oi the latter procedure, note the following:

Pounds Water 1,200 Aqueous solution of caustic soda of 25% strength naphthenic acid than the normal compound would require. On a percentage basis, it contained 33% of the amount required to form the normal compound.

Yield of the composition: approximately 264 lbs. of dispersion te, containing 70% total solids-18% copper.

The advantage of the procedure of this example is that the physical bulking of the hydroxy metal soap magma in the filter press is reduced by the omission of part oi. the organic acid and this means that a smaller bulk including less water need be handled in the filter presses.

The naphthenic acid which forms part of Solution C reacts completely through the dehydration cycle, so that the end product, namely, the hydroxy copper naphthenate, is identical in composition with the copper hydroxy naphthenate of Example 1 wherein the total amount of naphthenic acid was present during the magma formation.

In the process of dehydration, sufllcient xylol is removed with the water distilling ed to yield 265 lbs. of a paste composition containing ap proximately 64% of the hydroxy soap-15% copper.

The composition represents a dispersion ofhydroxy copper oleate in a mixed vehicle.

The formula contains 228 pounds oieic acid less than the normal compound would require and on a percentage basis, it, contains approximately 34. of the amount required to .form the normal type.

v Erma: 4 Solution A Pounds Water 1,200 Aqueous solution 25% of caustic soda- 288 Tall oil (said No. 160) 200 Solution B Pounds Copper acetate (32% copper)---- 153 Water 800 Solution C Pounds Solvesso" #3 a petroleum solvent) 800 In the dehydratin process sumoient "Solvesso" is removed to yield 408 lbs. or a csition containing approximately 63% of the hydroxy copper soap-12% copper.

The composition represents a dispersion of hydroxy copper tallate in a volatile solvent vehicle the normal compound would require. On a percentage basis it contains approximately 89% of the amount required to form the normal coppertallate soap.

Solution A Pounds Water 900 Flake caustic soda (76% N) 60 Tall 01 250 Anti-oxidant (alipha-naphthol) 3 After the dehydrating process, the weight of the composition is adjusted to 470 lbs. The composition then contains approximately 76% hydroxy copper soap-10% copper. The product reprts a dispersion of a mixed hydroxy copper tallate-naphthenate soap, in a volatile vehicle. The formula contains only 61% of the amount of tall oil-naphthenic acid required to form the normal copper soap.

PLE 6 Solution A Pounds Water 2,000 25% aqueous solution of caustic soda 350 Solution B Pounds Water 1,500 Copper sulfate (25% copper) 285 Solution C Pounds Petrolatum 850 Naphthenic acid (acid-No. 220) 200 After the process of dehydration, the weight of the composition is adjusted to 46 0 lbs. This composition which is in paste form represents a dispersion 0! hydroxy copper naphthenate in a non-volatile vehicle. The metal content of this paste is approximately 15%. This formula conl e formula contains 309 lbs. less tall oil than mm; only 36% of the amount acid yvhich would be required to form the normal copper soap.

Exams: 7

1000 lbs. or a hydroxy copper naphthenate dispersion paste, prepared as described in Example 1, are commingled with: v

2000 lbs. of a mineral spirits solution of normal copper naphthenate, such solution carrying 9% copper content.

There is thus obtained 3000 lbs. of a composition representing a combination oi! a hydroxy copper soap with a normal copper soap-the total copper content of this formula being approximately 12%.

' Exmm 8 500 lbs. of a hydroxy copper soap, obtained as described in Example 2,' is commingled with:

50 lbs. 01' normal mercury compound 01' mercury content. A

This process yields 550 lbs. 0! a composition representing a combination of a hydroxy copper soap with a normal mercury compound.

Solution A Pounds Water 800 aqueous solution of caustic soda. 250 Oleic acid (acid No. 195) 200 Solution B Pounds Water 1,200 Lead acetate (54% lead) 300 Solution C Pounds Mineral spirit: 500 Petroleum res In the pr c o i smllcient zyloi is remover; so yield 250 lbs. of end. product. This represents mobile diaper clan of mixed copper zinc hydroxy soap in vehicle. The metal contents are approximately:

Percent Copper re Zinc 4 This formula contains only 64% of the acid which would. be required. to form the normal soaps.

EXAMPLE 10 Solution; A I

Pounds Flake caustic soda so Water 1,100

Naphthenic acid (acid No. 2 20) 220 Hydrogenated rosin (acid No. 160) 10 Solution 5 Pounds acetate (54% lead) 428 Water 1.200

Solution C Pounds Hi h flash na htha 400 The weight of the end product obtained after dehydration is adjusted to 770 lbs. This composition represents a dispersion of hydroxy lead soap or two acids in a volatile vehicle. The metal content of this formula is approximately 30% lead. The formula contains only 48% 01" the full amount 01' acid which would be required to form the normal soap.

After the process or dehydrating, the weight or the resultantend product i adjusted to 650 lbs. The composition represents a dispersion of hydroxy lead oleate in a vehicle. The lead content of the formula is 26%. This formula contains only 45% 01 the full amount of acid required to produce the normal lead soap.

Exsuw: 12

Solution A Pounds Water 200 Caustic so 57 Naphthenic acid (acid No. 230).; 1st

Solution B Pounds Cobalt sulfate crystals (20% cobsltitilt? Winter 800 Solution C Mineral spirit Neutral rosin oil 200 After tlehydrationfthe weight of the em'i mod not is adjusted to 8&5 lbs. The composition represents a dispersion of hyolrmzy cobalt hash, thenate in 2. vehicle. content is proximately 5%. This formula contains 53% less acid the normal cobalt haphthenate would rec aim.

EXAMPLE 1E3 Solution A.

Pounds Water use 10% aqueous solution of caustic soda ass Tall oil (acid No. 160) z-ethylhexoic acid (acid No. soc) 100 Solution 23 Pounds Iron sulfate (20% iron) 21?. Water 600 Solution C V Pounds Xylol 500 After the dehydration process, the weight of the resultant end product is adjusted to 525 lbs. This composition represents a dispersion of hydroxy iron soap in a volatile vehicle. The metal content is 8%. This formula carries only 55% of the full amount of acids required to form the normal iron soap.

aeeaseo resents a mixture of hydroxy manganese naphthenate-benzoate in a volatile vehicle. The metal content is This formula contains only 75% of the full amount of acids required to obtain the normal manganes soap.

EXAMPLE Solution A Pounds Water 1,200 Aqueous solution of caustic soda, 25% concentration 233 SoZutionB I Pounds Copper sulfate crystals 190 Water 700 Solutions A and B were commingled under agitation. The copper hydroxide which was formed precipitated out in the form of a water-insoluble magma. This was then commingled with Solution C which comprises:

Pounds Sovosol 200 Naphthenic acid (acid N0. 210) 129 The weight of the end product after dehydrating was adjusted to approximately 264 pounds. The end product represents a dispersion of hydroxy copper naphthenate in a volatile vehicle. The formula contains 70% of the hydroxy copper naphthenatel8% copper. The composition carries only 83% of the amount of naphthenic' acid which would be required to form the normal compound.

The various hydroxy soaps to which I have referred may be used for a wide variety of purposes. For example, and without limitation, they may be employed as fungicides, as active ingredients in anti-fouling ship bottom paints, as insecticides, as mildewproofing agents, as catalytic agents, as paint and varnish driers, ink driers, linoleum composition driers, as agent to prevent loss of drying on ageing of paints and other coating compositions, as wetting agents, etc. I

The metal soaps produced, as hereinbefore described, may be used as the sole metallic soap constituent of other compositions as stated, or may be used in combination with other metallic soaps in such compositions. For example, as a fungicide it may be desirable to employ a combination of normal. copper naphthenate and my hydroxy copper naphthenate. It is possible for this purpose to mix together copper hydroxy soap dispersion, produced as hereinbefore described, with a normal copper soap either in the same or in difierent quantities as may be desired. Such a mixture may then be further associated with other ingredients to form, for example, a treating medium for the fungicidal-water-proofing and flame-proofing treatment of textiles.

Another combination which has been found to be of considerable utility comprises a mixture of the hydroxy lead naphthenate dispersion of this invention with other metallic naphthenates prepared by conventional methods, e. g., it may be desirable to incorporate into a coating composition, such as a paint, a plurality of metal soaps which may include my hydroxy lead naphthenate dispersion and cobalt naphthenate and manganese naphthenate made by conventional methods.

Having thus fully described the invention, What I claim as new and desire to secure by Letters Patent is: i

1. Process of producing a dispersed hydroxy heavy metal soap in a dehydrated organic vehicle, which comprises: thermally dehydrating in a sub stantially water immiscible organic vehicle an aqueous magma comprising the reaction product of an alkali soap or at least one substantially water-insoluble non-volatile organic acid, free alkali hydroxide and a sufilcient quantity of wetter-soluble salt of at least one heavy metal to completely react with the alkali soap and the free alkali hydroxide, whereby said hydroxy heavy metal soap is finally dispersed in substantially insoluble form in said dehydrated organic vehicle.

2. Process of producing a dispersed hydroxy heavy metal soap in a dehydrated organic vehicle, 1mm comprises: thermally dehydrating in a substantially water immiscible organic vehicle an aqueous magma comprising the reaction product of an alkali hydroxide and a sufiicient quantity of at least one water-soluble heavy metal salt to completely react with the alkali hydroxide, there befijg present in said vehicle during said dehydratii step a quantity of at least one substantially water-insoluble non-volatile organic acid in an amount insufllcient to produce the normal salt of such heavy metal but sufficient to produce hydroxy metal soap, whereby said hydroxy heavy metal soap is finally dispersed in substantially insoluble form in said dehydrated organic vehicle.-

3. Process of producing a dispersed hydroxy copper soap in a dehydrated organic vehicle, which comprises: thermally dehydrating in a substantially water immiscible organic vehicle an aqueous magma comprising the reaction product of an alkali soap of at least one substantially water-insoluble non-volatile organic acid, free alkali hydroxide and a sufficient quantity of a water-soluble copper salt to completely react with the alkali soap and the free alkali hydroxide, whereby said hydroxy copper soapis finally dispersed in substantially insoluble form in said dehydrated organic vehicle.

ARTHUR IWINICH.