US2108282A - Process of bleaching beeswax - Google Patents

Description

Patented Feb. 15, 1938 PATENT OFFICE raoonss F BLnAonING- BEESWAX Donald J. Campbell and Le Roy P. London, Niagara Falls, N. Y., assignors to E. I. du Pont de Nemours & Company, Wilmington, DeL, a corporation of Delaware No Drawing.-

13 Claims.

This application relates to a process of bleaching-and more particularly to a process especially adapted for the bleaching of waxes, particularly waxes of animal origin such as beeswax. More 5 specifically, it relates to a process of bleaching which utilizes peroxides as the active bleaching agents, more particularly hydrogen peroxide and an alkali metal peroxide such as sodium peroxide. The invention disclosed in this application is, in

part, a continuation of-that disclosed in the copending application of Reichert, Campbell, Hinegardner and-London, Serial Number 752,114, filed November 8, 1934 and entitled Process of bleach of this invention is in some respects an improvement on that disclosed in said co-pending application.

The beeswax now commercially obtainable in the market is usually classified mm two distinct groups. Domestic beeswax, or the-wax sold by American bee keepers is usually a dark colored material, and it is impossible to bleach this wax to a satisfactory white colorby the usualair and sun bleaching methods now widely practiced commercially. Imported wax. on the other hand,

is 'generallyrelatively" easy to bleach by the agening application, Serial Number 752,114, the proc-'- ess therein disclosed is especially adapted for the bleaching oi' dark colored domestic waxes, dimcultly bleachable importedwaxes and various blends of imported and domestic waxes.

' However, the processor said co-pending application requires the application of a decolorizing or adsorbent medium such as activated carbon and/or iullers earth in every instance.

.wax which cannot bev economically recovered by the bleacher and which is usually discarded with the spent decolorizing'agent. Accordingly, with. t5 the intention of improving the processor that applicationfso as to eliminate the necessity for a. decolorizing step in as many instances as possible and with the aim of utilizing the active-oxygen yielding bleaching agents more economically an 50- improved process has been developed which will now be more iully described.

It is therefore one of the objects of this invention to improve the process of said co-pending application, Serial Number 752,114 in order to 55 eliminate the necessityfor treatment with e, de-

ing. The process forming the subject matter.

Thisis 40 somewhat objectionable as, generally, a @colorizing medium 6! this nature absorbs considerable Application April 30, 1935, Serial No. 19.071

colorizing medium such as charcoal, fullers earth, silica gel or alumina gel, or' mixtures of these adsorbents, in as many circumstances as possible. However, we have not succeeded in completely eliminating the step of treating the molten beeswax with an adsorbent or'decolorizing medium since in the bleaching of various dark-colored waxes it is still essential that this step be a part of our process. But inthe bleaching of waxes which are not as dark as the more discolored specimens of domestic wax, such as wax blends, or beeswax from the various less diillcultly bleachable imported sources, we have found it possible to dispense with the step oi discolorizing the molten wax with an adsorbent agent or' mixture of'adsorbent agents.

Moreover, it is another oi! the objects 01 this invention to employ the active oxygen-yielding bleaching agent, or the active-oxygen yielding agents, in such a manner that they are most efl'ectively utilized in the bleaching. we propose in our preferred procedure to, use two bleaching treatments with active oxygen-yielding com'-' The latte solution is alkaline in reactiomg" m 1 coniunctionfivithfl the first of these active ozwgen bleaching" steps" we iind it advisable and highly desirable to use a bleaching promoter to render more'eifective the bleaching action of the hydrogen peroxide solution. We believe that the use of a promoter in connection with the bleaching of wax is broadly novel, and the presence oi a promoter is of. considerable advantage in the economical use of the bleaching agent.

Thus we utilize two separate bleaching steps with active oxygen-yielding compounds, one with an acid bleaching solution and one with an alka-' line bleaching solution.' 'We have found that treatment with both acidic and alkaline active- .oxygen bleachfsolutions is essential in order to bleach beeswax successfully. 01' course, for hydrogen peroxide in the first, bleaching step any equivalent substance may be substituted such as an acid solution of a metal peroxide, an acid solution of a perborate, perc'arbonate etc. Similarly in the alkaline bleaching step equivalent materials may be utilized such as alkaline'hydro gen peroxide solutionasodium or other metal perborate, percarbonate or other per-salts.

These and still further objects of the invention will be apparent fromthe ensuing disclosure which is the best means known to us of carrying Oil; the improved bleaching method in the commercial bleaching of various waxes and particularly of beeswax.

We find it preferable first to wash the wax with a dilute acid such as dilute sulfuric acid. It is desirable that a hot solution of the acid be used, preferably one heated to the boiling point and, at least, to a temperature in excess of the melting point of the wax.

When sulfuric acid solution is used for the washing we have found a dilute solution ranging in concentration from 2 to 10% (by weight) to be suitable. Ordinarily we prefer to use a dilute acid containing 2% of sulfuric acid, the temperature being maintained at the boiling point and the amount of dilute acid being approximately equal to the amount of wax. A treatment time ranging from one-quarter hour to one hour is desirable and one-half hour will generally be found to yield the best results with both imported and domestic beeswaxes.

The amount of acid, as distinguished from the concentration of the dilute acid solution, is not importantneither is the volume or weight of the dilute acid wash liquid, as long as enough is present to obtain effective washing. We have found that the concentration of the acid is the important factor and'this should range from about 2 to 10%, these values being concentrations by weight.

In place of sulfuric acid, dilute oxalic acid of substantially the same concentrationl may be used. Or, if desired, the wax may be freed of impurities, which must be removed before bleaching, by filtering the beeswax while in the molten state. As an alternative procedure, a treatment with activated carbon and fullers earth similar to that described later in this application may be used. However, a less amount of the adsorbents is suitable, 1 to 2% fullers earth and char coal will be found entirely sufiicient, for this step. Since the same effect can be obtainedby the use of an acid wash or by simple filtration we do not advocate treatment with adsorbents at this stage because the expense of bleaching the wax is thereby increased.

A tank having the shape of a separatory funnel, is conveniently used during the step of washing the wax with a,dilute acid. The beeswax, which is of course, molten, will tendto float on top of the acid if the mixture of wax and acid is permitted to stand, and the dirt which is removed will settle to the bottom of the tank. After vigorous agitation of the acid and wax for a period ranging upto one half hour, the dirt may be removed from the bottom of the tank and the wax is drawn of! in the molten state and conveyed to a second container. In order that efficient bleaching may occur it is necessary that the wax be free from all mechanically-held impurities.

To the molten wax we now prefer to add the bleaching promoter. Zinc oxide'is the promoter that we have found eflective and we prefer to use amounts up to one-half per cent by weight of the molten wax. We have used amounts as low as 4% by weight with'success, but find that when the zinc oxide is present in amounts less than this latter value, the bleaching action of the hydrogen peroxide is not as effective. zinc oxide should be thoroughly incorporated in the molten wax by vigorous stirring for approximately 15 minutes.

Commercial 100 volume hydrogen peroxide solution 'Which is acid in reaction) in amount equivalent to /3% by weight of the wax s 1.1 3

The,

. aroaaec added. Stirring should be continued and at'the. end of another half hour /z% more of 100 volume hydrogen peroxide should be added. Similarly, three other additions of hydrogen peroxide in amounts equivalent to /g% by weight of the wax should be added to the molten beeswax at the end of approximately one hour, one hour and a half, and 2 hours. During all this period vigorous stirring is continued for a period of approximately 5 hours or until practically all the oxygen content available in the mixture has disappeared.

While we have disclosed the use of 100 volume hydrogen peroxide solution (which is a product sold in great volume commercially as a solution having a pH value between 1 and about 6) we do not mean to restrict our process to the use of such a solution. It is, of course, perfectly possible to use 10 volume hydrogen peroxide, 25 volume hydrogen peroxide, 50 volume hydrogen peroxide, 200 volume lnldrogen peroxide, or any other solution obtainable commercially. Similarly other acidic solutions equivalent to a solution of hydrogen peroxide and having a pH value of less than 7 are suitable, for example acid solutions of alkali metal peroxides such as sodium peroxide, etc. The numerical amounts suggested as suitable are based on 100 volume hydrogen peroxide solution and if other active oxygenyielding solutions are used quantities yielding substantially an equal volume of active oxygen should be employed.

If desired, the zinc oxide promoter and the 100 volume hydrogen peroxide solution may be added together instead of successively, but it has been determined from numerous experiments that the greatest utilization of the peroxide occurs when the promoter is addedfirst and then the hydrogen peroxide solution is added in successive increments- We do not mean by this that it is essential to .add exactly 0.5% of 100 volume hydrogen peroxide at the end of any specifiedtime but we have found it most desirable to add the promoter and then to distribute the addition of the 100 volume hydrogen peroxide solution over a period in the neighborhood of one to three hours. If desired,.the addition of the hydrogen peroxide solution may be made continuously or at shorter or longer intervals over the entire period of treat-. ment which has been determined to be about 5 hours for most efficient bleaching. During all' this time stirring should be continued and, of course, it is possible that the active oxygen content of the hydrogen peroxide may be completely used up in a period of less than 5 hours or perhaps a period somewhat longer than 5 hours may be necessary. The proper duration of the bleaching period can be very easily determined in commercial operations by testing a small portion ofthe liquid or molten wax for active oxygen content using a well known indicator such as potassium iodide-starch paper. So long as anycoloration is obtained when this paper is contacted with the mixture of wax and liquid, active oxygen is still available. The obtainment of a coloration indicates that the treatment should be continued until the quantity of unused active oxygen is at least substantially reduced. However, any of the active oxygen yielding material not utilized 7' in this step will be carried on into the subsequent bleaching operation and will not be lost. Stirring hydrogen peroxide. However some equivalent means to insure thorough agitation may be used, such as blowing air through the mixture.

,After approximately 5 hours, the molten wax Should be drawn off and poured into a tank which contains approximately four times as much solution' as the volume of the wax. This is a solution of an alkali metal peroxide, such as sodium peroxide, in water. The quantity of sodium peroxide used should be equivalent approximately to 5% of the weight of the wax. Of course, an alkaline solution of hydrogen peroxide of equivalent active oxygen concentration maybe utilized during this step. Similarly, any other source of A active oxygen which yields a solution which is alkaline inreaction, such as alkali metal perborate, alkali metal percarbonate, and various metal peroxides, may be utilized.

If desired, the molten wax may be first thoroughly washed in dilute acid solution, such as dilute sulfuric acid of approximately 1% concentration, in order to remove the zinc oxide promoter, before it is transferred to the tank containing the dilute alkaline active oxygen yielding solution. We have found that the removal of the promoter prior to the alkaline bleaching step will yield improved results. However, this step is not essential and we prefer to wash the wax prior to treating it with a solution of an alkali metal peroxide or an equivalent solution, such as an alkaline solution of dilute hydrogen peroxide, only in those instances wherein it can conveniently and economically be done. n The wax, which is of course maintained in the molten condition, is thoroughly emulsified with the alkaline active oxygen yielding solution, which we shall refer to as sodium peroxide solution, by thorough agitation. The temperature is maintained within the range ISO-180 F. we have found that it is not desirable or necessary to use more than 5% of alkali metal peroxide in this step (based on the weight of the wax) when a a temperature .of 180. F. is maintained because a larger quantity of alkali metal peroxide converts the wax to a condition wherein it fails to meet U. S. P. specifications. If the'temperature is maintained at a lower value, in the neighborhood of the quantity. of sodium peroxide or other alkali metal peroxide .employed may be raised as high as 8% with resulting improvement in color and without chemical change or injury 7 to the wax. In general we have found amounts of alkali metal peroxide ranging from 3 to 5% to be suitable when a temperature of F. is

maintained and amounts ranging from 4 to 8% when a temperature of approximately 160 F. is maintained. All these quantities are by weight, based on the weight of the beeswax being treated. Where other materials are substituted for the alkali metal peroxide'such as a dilute solution, of hydrogen peroxiderendered alkaline by the addition of alkalining agents, sodium perborate, sodium percarbonate, etc., amounts of these compounds suflicient to yield a solution of substantially equivalent active oxygen content are utilized.

The emulsified wax and alkali metal peroxide solution should be maintained at the selected temperature within the range 160-180 F. for a considerable period of time which, in commercial practice, may conveniently be an overnight period. A treatment period ranging from 6 to 12 hours has been found satisfactory. At the conclusion of this period, or in the morning, the

emulsion is broken by the addition of an acid such as sulfuric acid or oxalic acid and a slight excess of acid over that amount necessary to neutralize the solution is introduced. The molten wax which then risesto the top of the vessel is withdrawn and rinsed free of acid in a'water bath.

' We have found that many grades'of imported wax are nowsufliciently bleached for commercial utilization and require no additional treatment. However, when treating the more diflicultly bleachable types of imported waxes and dark colored' domestic waxes it may be desirable to subject the molten wax to the action of adsorbing agents. Conveniently this may be a step involving treating the wax with activated carbon and/or fullers earth utilizing the procedure described in the following paragraph.

The darker colored waxes which are vdiflicult to bleach and which have not been satisfactorily lightened by the foregoing process should therefore be subjected to the action of adsorbing agents. We propose to agitate the molten beeswax for an hour and one-half with an adsorbent agent such as a mixture of 1% activatedcarbon and 8% fullers earth at a temperature of 180 F. These amounts are by weight based on the weight of the beeswax. If desired, the mixture of activated carbon and fullers earth may be replaced by activated carbon aloneor fullers earth alone.

However, uneconomically large amounts of ac-- tivated carbon, of the order of 5-10%, are necessary when it is used alone, and the quantity of fullers earth necessary is similarly so large that been found satisfactory provided there is 10% of fullers earth present, while amounts of activated carbon as high as 4% are suitable under which circumstances the fuller's earth content may be reduced to approximately 4%. All these percentages are as previously stated, based by weight on the weight of the wax.

' The molten wax should now be thoroughly agitated for a period of time ranging from 1 to 2 hours, preferably for aboutv an hour and a half with the adsorbent material, the temperature being maintained preferably at approximately 180 F. or some temperature above the melting point of the wax. At the conclusion of this process the mixtureshould be run through a filter to remove the adsorbent. Even the most darkly colored and diflicultly bleachable waxes will be found to be'lightened in color to a satisfactory degree of whiteness at the conclusion of this step.

In the foregoing process we haveincreased the amounts of v 100 volume hydrogen peroxide solution utilized after the acid wash treatment to approximately 8% with only slight improvement not only bleached to a degree of whiteness satisfactory for use in such industries as the cosmetic industry in the praparation of cold creams,- etc..

"but also that the creaming properties of these waxes have not been injured by the treatment.

vits disclosed in the previously mentioned co-pending application; Serial; Number 752,114, the deof beeswax in the process has been a seriousobjection to many previously suggested bleaching 1' processes paired by the process.

It has been found that waxes bleached in accordance with the method of this application are entirely suitable for all cosmetic uses and their creaming properties have not been im- It is evident that our process is much more rapid and much more satisfactory than the uncertain and primitive methods now employed in the beeswax bleaching industry. The process is readily carried out commercially, requires no expensive equipment and is readily attended to by unskilled operators. While it is particularly adapted for the bleaching of beeswax, and in this respect is a contribution of considerable value to the art, it may also be used for the bleaching of other similar waxes and we do not wish to be restricted in the scope of protection accorded to beeswax alone.

It is to be understood that although hydrogen peroxide and sodium peroxide have been taken as illustrative in describing our process, various other peroxides can, of course, be used, e. g., the

compounds of other alkali and alkali earth metals are suitable, as is any. compound capable of yielding hydrogen peroxideunder the conditions described as illustrative of our process. Other per-salts such as metal perborates and alkali vmetal percarbo-nates are also suitable.-

-*-It is also to be understood that the various amounts, concentrations, times and temperatures claims.

given in the foregoing description are to be considered as illustrative of our preferred method and that our improved process is notspecifically restricted to these conditions, manipulations and amounts. The amounts specified have been mentioned merely in order to furnish a complete disclosurefof the best method known to us of practicing the invention, and we donotwish to be restricted except as necessitated by the appended It is obvious that various changes may be made in the procedures, temperatures, treatment times and-the amounts of chemicals and for other agents specified without departing from the scope and spirit-of our invention; U

.Wherever; in the appended claims, reference is clude withinthe scope of this term any material which is capable of yielding hydrogen. peroxide when in solution or when .utilized under the conditions set forth in the foregoing description, e. g. the various persalts, percarbonates, perborates, peroxides, etc.

As examples of our novel process thefollowing may be given:- l

Example 1' One kg. of a dark colored imported wax was to be bleached to a degree of whiteness sufiicient to render it suitable for use as an ingredient in cold creams. The beeswax was placed in a 3% solution-of dilute sulfuric acid in amount equal approximately to the weight of the wax or 1 kg.

The acid and wax mixture was boiled for half an I hour while being stirred and at the end of that time the solution was .allowed to clear. The sediment which: dropped down into .the bottom of the. vessel was removed, and the molten wax was then drawn over into another vessel.

To the wax 5 g. of zinc oxide was next added and thoroughly interspersed therein by stirring.

The wax was maintained in molten ,eondition during the entire process and g. of commercial 100 volume hydrogen peroxide solution was added the additions being spread over a period of 5 hours. The mixture of zinc oxide and hydrogen peroxide was stirred constantly during this period by a mechanical stirrer, and the temperature was kept at about 180 F. During this period the dark brown color of the wax was changed to a light yellow shade.

The wax, still molten, was then run into 4 kg. of water in which 50 g. of sodium peroxide had been dissolved. An emulsion was formed by stirring the mixture and this emulsion was maintained at 180 F. for about a period of 12 hours. At the end of this bleaching step the wax was recovered by neutralizing the alkali present in the mixture by adding such a quantity of sulfuric acid that a slight excess of acid was present.

Because the wax that was being bleached was an exceptionally dark colored wax which could be bleached only with difiiculty it was not white enough at the conclusion of this step. The following additional treatment was therefore necessary. 4

To the molten wax 50 g. of fullers earth and 10 g. of activated carbon was added. The wax and the adsorbent agents were brought into thorough and repeated contact with one another by stirring for 1.5 hours, the temperature being meanwhile maintained at 180 F. The mixture was then filtered and the wax was separated from the adsorbent agents and permitted to solidify. The final product was a bleached beeswax of excellent quality and of a high degree of whiteness. The creaming properties of the wax,

' Example 2 1 kg. of dark colored but comparatively readily bleachable imported wax was placed in a 3% solution of dilute oxalic acid, in amount equal approximately to the weight of the wax. The acid and wax mixture was boiled for half an hour, vigorous agitation being imparted to the mixture. At the end of that period the sediment which dropped down to the bottom of the vessel was removed and the supernatant molten wax was drawn over into another vessel.

Zinc oxide in amount equal to /2% by weight, I based on the weight of the wax, or 5 grams was now added and thoroughly incorporated in the molten wax by' stirring. Forty grams of commercial 100 volume hydrogen peroxide solution having a pH of about 4.5 was then added. The

temperature of the mixture was maintained at 180 F. for four hours, vigorous stirring being constantly employed.

The molten wax was then washed in /9 dilute sulphuric acid solution to remove the zinc oxide. It was then emulsified with a solution containing g. of caustic soda and 60 g. of volume hydrogen peroxide solution. The total weight of the alkaline active oxygen yielding solution was about 4 kg. The-temperature was maintained at F. for 12 hours. The pH of this emulsion, as measured, was 12.3.

At the end of the twelve hour bleaching period the emulsion was neutralized by the addition of sulfuric acid and the wax separated as a supernatant molten layer.

When it had solidified it was found to be of an excellent degree of whiteness. Its creaming properties had not been impaired and it was suitable for every cosmetic use.

acid at an elevated temperature above the melt to the action of an alkaline peroxide" solutio'rr and then subjecting the We claim:

1. In a process of bleaching beeswax the step which comprises treating the wax while in a molten condition with a solution oi. hydrogen peroxide in the presence of zinc oxide as .-a bleaching promoter.

'2. In the process of bleaching beeswax the steps which comprise washing the wax with a dilute solution of an acid selected from the group which consists of sulfuric acid and oxalic ing point of said wax, subjecting the wax to the action of acidic hydrogen peroxide under conditions such that intimate contact between said wax and said hydrogen peroxide is secured, there being present zinc oxide as a bleaching promoter, ax to the action of sodium peroxide in alkalin solution under conditions such that intimate contact between said sodium peroxide solution and wax is secured, said wax being maintained in the molten condition throughout.

'3. In the process of bleaching beeswax the steps which comprise washing the wax with warm dilute sulfuric acid solution while the wax is in the molten condition, subjecting said wax to the action of acidic hydrogen peroxide in the presence of zinc oxide as a bleaching promoter under conditions such that intimate contact between said wax and said peroxide is secured, then emulsifying the wax with an alkaline metal peroxide in alkaline solution, andfinally subjecting said wax to the action of an adsorbent agent,

said wax being maintained in the molten condition throughout.

4. In the process of bleaching beeswax the steps which comprise subjecting the wax to the action of a dilute acid selected from the group which consists of sulfuric acid and oxalic acid at an elevated temperature above the melting point of said wax, then subjectingthe wax to the action of acidic hydrogen peroxide solution in the presence of vzinc oxide as a bleaching promoter under conditions such that intimate contact between said wax and said peroxide solution is secured, and finally subjecting the wax is acidic in reaction under conditions such that intimate contact between saidwax and said peroxide solution is secured, said treatment being can'ied out in the presence of zinc oxide as a bleaching promoter, subjecting said wax to the action oil a solution of sodium peroxideunder conditions such that intimate contact between said I: l: secured, separating 011 said wax and finally treating said wax' with an adsorbent agent in order to remove dark colored discoloring compounds,

said wax being maintained in the molten condicolored discoloring materials.

tion throughout.

6. In the process of bleaching beeswax the steps which comprise first subjecting the mixture to the action of a solution of hydrogen peroxide which is acidic in reaction under condi- 1 ne peroxide solution and said wax is' tionssuch that intimate contact between said beeswax and said peroxide solution is secured, and then subjecting the wax to the action of an alkaline peroxide solution under conditions such that intimate contact between said alkaline solu-- tion and said wax is secured, said wax being maintained in the molten condition throughout.

7. In the. process of bleaching beeswax the steps which comprise first subjecting the wax to the action of a commercial volume solution of acidic hydrogen peroxide under conditions such that intimate contact between said peroxide solution and said beeswax is secured, and then subjecting said wax to the action of ,a solution of an alkali metal peroxide under conditions such that intimate contact between said alkali metal peroxide solution and said wax is secured, the solution being maintained alkaline during said latter step, and said wax being maintained in the molten condition throughout.

8. In the process oi bleaching beeswax the steps which comprise first subjecting the wax to the action ot a solution of hydrogen peroxide which is acidic in reaction in the presence of zinc oxide as a bleaching promoter under conditions such that intimate contact between said beeswax and said peromdesolution is secured, and. then subjecting said wax to the action of an alkaline peroxide solution under conditions such that intimate contact between said alkaline solution and said wax is secured, said wax being maintained in the molten condition throughout.

. 9. In the process of bleaching beeswax the steps which comprise first subjecting the wax to the action of a commercial 100 volume solution or acidic hydrogen peroxide under conditions such that intimate contact between said solution and said beeswax is secured and in the presence oi zinc omde as a bleaching promoter, and then subjecting said wax to the action of a solution of hydrogen peroxide which is alkaline in reaction under conditions such that intimate contact of said alkaline solution with said beeswax is secured, said wax being maintained in the molten condition throughout.

it. In the process of bleaching beeswax the steps which comprise first subjecting the beeswax to the action of a commercial 100 volume solution of acidic hydrogen peroxide under conditions such that intimate contact between said beeswax and said solution is secured and in the presence of zinc oxide as a bleaching promoter, andthen subjecting said beeswax to the action oi a solution of sodium peroxide under conditions such that intimate contact between said alkaline peroxide solution and said beeswax is secured, said wax being maintained in the molten condition throughout.

I -11.'In the process of bleaching beeswax the steps which comprise treating the wax with a dilute solution oi sulfuric or oxalic acid having a concentration ranging from 2-10% at an elevated temperature above the melting point of said wax, then rinsing the wax with water, subjecting the wax to-the action of a solution oi hydrogen peroxide which is acidic in reaction in the presence of zinc oxide as a. bleaching promoter, then subjecting the wax to the action of an alkaline peroxide solution, and finally subjecting the wax to the action of activated carbon and fullers earth in order to remove additional quantities of dark 12. In the process oi bleaching beeswax the" steps which comprise first subjecting the wax to the action of a warm dilute acid selected from from 240%, washing to remove as large an amount of free acid as possible, subjecting the wax to the action 01' 108 volume acidic hydrogen peroxidesolution in amounts ranging from 1.5 to 8% by weight in the presence of zinc oxide as o. bleaching promoter, subjecting the wexto the action of a solution oi sodium, peroxide of concentration ranging from 3 to 8% at a, temperature within the range 160 to 130 F. and finally subjecting the wax to the action 01 a mixture of activated carbon and fullers earth in amounts 7 ranging from e-10% at 8; temperature of 160 to oxalic acid, the concentration of said acid being 13' In the process of bleaching beeswax the steps which comprise treating the wax with a dilute solution of sulfuric acid at an elevated temperature alcove the melting point of said wax, said. wax being in the molten condition, then subject- 1113 said we to the action of commercial 100 volume acidic hydrogen peroxide solution in the presence of zinc oxiole as a bleaching promoter, and finally emulsifying said wax with a dilute solution yielding hydrogen peroxide which is alkaline in reaction, said beeswax being maintained in the molten condition during the entire process.

DONALD J. CAMPBELL. LE ROY P. LUNDON.