US3004992A - Process for the separation of waxy components from sterol-containing materials - Google Patents

Description

United States Patent '0 a ma s... Y. rnqcnss E0 3. SEPARAT O ,.0E consumers FROM SIEROL-CONTAINW Sidney M l r, t, ran. Cha es Ma y e ty nneapolis, and Robert IL Chang, St. Paul, -Minii., 8S- signers to Mills, Ina, a corporation of Delaware No Drawing. Filed June 18, 1 956, Ser. No. 591,809 9 Claims. (Cl. 2609939725) This invention relates'to a process for removing wax and wax alcohols from various oils and residues containn r l i im s q an it es a a d tomp n s, More specifically, this inv'enti'on relates to a process for removing wax alcohols from vegetable 'oils and stab er sidhs y selective r s a i n tsby enabling the s parations: sterols which are -substantially free of these wax constituents.

In h ph rmassntis l and ela e fields, stsrf ls are assuming a 9 mb are: "on mp i nq vN1 i e ou o ccur natural y an w en epar ted m y be used in their pre nt .i or may he mo fied by known m c l rr r to pr du cinnmerce. Wit ii il d 9'. 1nd :6 fi io l 'hit is app ren tha for p rating st ro s beome e y ish rsr sters ststi t in ra s in complex, mix ur t with oth compounds h f y 's y er des, fat acids, hydrocarbons, wax alcohols, and resins. Various methods have been proposed for separating these components and the p nsir' met od employed a the pres nt t m is solvent fractionation, The solvent fractionation may or may not be carried out in conjunction with saponification of the complex mixture.

Various sterols occur in most every type of vegetable matter. common sources of sterols are the well-known and abundantly available fats and oils of commerce, such as soybean oil, corn oil; cotton seed'oil, and peanut oil. Another source ct ste ol somewhatrelated but wh contain a r latiye y la g amoun of w y onstitu nts such as wax s and a alc hol a compa e t the above so ce a e oi endan er can These waxy constituents pr s t spe i p b ems in the separation and isolation of sterols when they are present in appre iable quan iti s. Thi invention mak s av i a commercially feasible process whereby sterols from m. containing ar PIOPOI QB o and alcohols may be separated in relatively pure form.

More specifically, this invention is applicable to those animal and vegetable oils and/or animal and vegetable residues which contain more than 2% of the waxy constituents and may contain as much as 20%. An illustrative vegetable residue abundant in large quanitis is is the filter mud or filter .cake which is a by-product in the processing of sugar critic for sugar. This mud conwaxy constituents from steroid rich materials.

tains, as its major constituents, a complex mixture of fatty I glycerides, fatty acids, wart wax alcohols,- sterols, hydrocarbons and resins.- Conventionally this mixture is 'refinedby known p'roc'edunes,- primarily solvent fractionation, to yield a hard fraction and an oily fraction; This oily fraction contains from 5 to 12% sterols. A detailed description of this separation appears in the Sugarcane Technical Report Series No. 3 issued by the sugar Research Foundation inc, New York, New York, in O tober .1 4 ntit ed, fW u nd F t y yc o Sugar Cane by Ro al '1, Batch, Although a hard wax fraction has been removed from the filter mud, the oily fraction still contains generally from 5 to 10% of a soft waxy traction. of su a cane oil it is this soft was traction that int rfer s with he iso ation tit-pure sterols from theoil, primarily for the reason that ittends 3,604,992 Patented Oct. 17, 1961 ice 2 to crystallize out with the sterols in the known solvent processes used for purifying and refining the oily fraction.

Another vegetable residue encompassed by the teachings of this invention is the complex mixture remaining after most of the free fatty acids and/0r rosin acids have been removed from the tall oil. It also is a complex mixture containing fatty acids, glycerides, waxes, wax alcohols, sterols, hydrocarbons and resins. Because appreciable quantities of wax alcohols are present in this product also, the isolation of pure sterols by solvent fractio'nation is again hampered by the tendency of the wax alcohols to crystallize out with the sterols.

The principal products presently available as sources of crude sterols which contain appreciable quantities of wax alcohols are sugar cane oil and tall oil. However, it willbe appreciated that this process is applicable to all crude sources of sterols containing large quantities of wax alcohols. In respect to the sterols from sugar cane oil,

it should be noted that they are particularly valuable sources of 'stigmasterol which can be transformed by know procedures to progesterone other steroidal hormones. We have discovered that the troublesome wax alcohols have a very low solubility in ethylene dichloride. For instance, at 0 C. the solubility of the wax alcohols is in the order of 0.004 to 0.005% by weight while at 20 Q. the solubility is still low, somewhat in the range of 0.1%. Depending upon the amount of wax alcohol present the selective crystallization may be performed in the rangeof 0 to 3.9" C. charm-ensue solubility in ethylene di-' ohloride enables us toprecipi'tate most of the waxy corrstituents out of an ethylene dichloride solution without precipitatingappreciable amount of sterols. It is possible in the case of those materials containing appreciable amounts of triglyceride to precipitate most of the wax esters and wax alcohols from the other constituents of the oil. oil, which has been freed from the trouble some alcohols and wax esters, may then be treated in a variety of ways to recover relatively pure sterols.

Thus, it will be 'seenthat two procedures are available and encompassed in this invention for the removal of In the first of these, the material containing the waxy constituents is mixed with warm ethylene dichloride and the mixture allowed to cool such that the wax constituents crystallize out. As an illustration 'of this method, equal proportions of sugar cane oil and ethylene dichloride are mixed together at elevated temperatures and the mixture allowed to cool to room temperature. If the cooling is carried out slowly it tends to promote the growth of large crystals and subsequent filtration of these crystals is facilitated. This mixture should then be cooled to a lower temperature such as 5 C. to complete the precipitation and then filtered or centrifuged to remove the precipitated waxy constituents. The ethylene dichloride may then beevaporated from the filtrate to recover an oil containing the major proportion of the sterols and a very small percentage of the waxy constituents. It is also possible that the minor amounts of waxy constituents remaining may be further separated from the sterols in a solution containing 5 to 20% solids and cooled to room temperature in order to precipitate a further waxy constituent. This oil can then be saponifie'd and extracted by known proce'dures'to yield the desired sterols. It will be appreciated that an additional advantage tothis process is afforded if ethylene dichloride is used in the subsequent processing to recover thesterol portion. v

A- modification of this process is the addition of a small quantity of water to the ethylene dichloride solution of the extracted uns'aponifiable matter to, hydrate and preeipitate the sterols which have been freed of the waxy constituents. The quantity of water used should be just enough to hydrate the sterol content of the oil, It will be appreciated that this quantity will vary according to the sterol content but for illustrative purposes it can be stated that the amount of water employed will generally be in the range of 0.1 to 1% by weight of water and preferably 0.3 to 0.5% by weight water. Vigorous agitation accompanying the introduction of water to the ethylene dichloride solution in order to disperse the water throughout the solution increased the effectiveness of this modification. Following the addition of water to the ethylene dichloride solution it is again permitted to cool, preferably to temperatures within the range of '5 to C., in order to crystallize out the hydrated sterols. This is possible due to the fact that hydrated sterols are less soluble than unhydrated sterols in ethylene dichloride. In addition to using water it will be appreciated that water-alcohol solutions may also be used to hydrate the sterols, such as 90% aqueous methanol. Here again,

alcohol having a melting point of 75-77 C. precipitated and was removed by filtration.

The filtrate on treatment with 2.5 by weight methanol and 0.4% by weight water immediately gave a crystalline sterol product. On standing at room tem: perature a total of 36.6 gms. or 4.5% of the original oil precipitated. The product melted sharply at 138139 C. which indicated that it was pure sterols. A second crop of crystals amounting to 16.5 gms. or 2.0% of the oil, was obtained by concentrating the ethylene dichloride filtrates from the first crop of sterols. The melting point of the second crop, however, indicated that it was not as pure as the first crop.

the amount of the alcohol and water to be employed will I vary according to the sterol content of the oil.

Sterols separated in the above fashion have been analyzed to determine their sterol content and have been found to generally be in the order of 95% sterols. Likewise, when sugar cane oil is employed the stigmasterol content of the sterol fraction has been shown to be i to 40% as calculated from its infrared absorption curves.

The second procedure suitable for use with the discoveries encompassed in this invention is to saponify the entire material with alkali and extract this mixture by known procedures to obtain an unsaponifiable fraction containing sterols, wax alcohols, hydrocarbons, resins, and other unsaponifiables. The crude unsaponifiable fraction is then dissolved in anhydrous ethylene dichloride and allowed to cool as described above which prev cipitates out substantially all of the wax alcohols. The

wax alcohols are then filtered or centrifuged out and the resulting filtrate treated in accordance with the teachings described above to obtain relatively pure sterols. Again the concentrations employed may be varied within wide K ranges but it has been observed that excellent results are EXAMPLE I Crude cane oil 808 g., was treated with 808 g. of dry ethylene dichloride and allowed to stand at room temperatures for 24 hours. The mixture was then cooled to 35 F. and allowed to stand for another 48 hours, and the wax was removed by filtration. Removal of the ethylene dichloride from the filtrate produced an oil amounting to 87.9% of the original cane oil.

The resulting oil was saponified by refluxing it for 3 hours with 604 gms. of 84% aqueous methanol containing 83.5 gms. of sodium hydroxide. The saponified solution was then diluted with water so that the ratio of oil to methanol to water was approximately 30:20:50 and th; diluted mixture was extracted with ethylene dichlon e.

The ethylene dichloride extracts amounting to 2900 gms. were treated with 6 ml. of acetic acid, filter aid and the mixture was filtered. This served to remove traces of colloid soaps that had carried over in the extracts after filtration. Evaporation of an aliquot of the extracts indicated that a total of 130 gms. of unsaponifiable material had been extracted which corresponds to 16.1% of the original oil.

The ethylene dichloride solution was then concentrated to 20% solids. This evaporation removed any water and methanol carried over into the extracts. 0n cooling to room temperature for several hours, 10.7 gms. of .a wax EXAMPLE H A sample of the oily fraction from sugar cane filter mud was saponified and extractedwith ethylene dichloride. The extracts were evaporated to yield a high wax containing unsaponifiable fraction which represented 36% of the original oil and which contained 34.0% sterols as determined by precipitation'of the sterols with digitonin.

Samples of this unsaponifiable fraction were dissolved in ethylene dichloride at concentrations of 3.1, 5.9,92,

12.4 and 15.2% by weight. The solutions were then cooled to 25 C. to precipitate the wax alcohols. .In all the solutions except the 3.1% solution a wax precipitate formed was filtered off. In the case of the3.1% solution, "cooling" to 5 C. gave a precipitate but was a mixture of wax and 76.9% sterols. In the case of the other solutions the yields of wax and the sterol'content,

of'the' waxes was as follows:

Percent Sterols Yield Wax Concentration of Solution Alcohol as Perin the We: cent of Total Fraction The filtrates from the above wax fractions were treated I with 2.5% by weight methanol and 0.4% by weight water to precipitate the sterols. A second crop of sterols was obtained by evaporating the volume of the ethylene dichloride, adding 2.5 by weight methanol and 0.4% by weight water and cooling to 25 C The yields and total sterol content of the two crops of sterols were as follows:

- Yield of Sterols Concentration of Original Solution as Percent of Percent Sterol Original Unin products saponifiable The stigmasterolcontent of the sterols obtained in these crystallizationsranged from' 22.0 to 44.3% with the first crop of sterols ranging. from 38.4% in the case p of the 15.2% solution to 44.3% in the case of the 5.9%

solutions.

Additional amounts of sterols of lower purity ranging from 61 to 79% sterols were obtained from filtrates of the first two crops by cooling to lower temperatures (40 -F.) and by further concentration of the solutions. Total yields ranged from 45-60% of the sterols originally present in the unsaponifiable fraction.

EXAMPLE III A sample of sugar cane unsaponifiables was obtained by saponifying-sugar cane oil and extracting thesapouifled mixture with ethylene dichloride. The yield of un-' sponi ables mo nted t 3 o h oil and c a ned 34% t ols- A 1. scr sm o t e nsa o fi b s wa i solved n e y ene d hlori e t 138K? a 2. o u 12 1- of glacial acetic acid and 45 g. of Superfiltrpl F.Q. filteraid were added and the mixture filtered to remove colloidal soaps, The filtrate was then cooled to 22 C. for several hours and then filtered after adding 3 to 4% Ce1i t e 535 filter-aid. A wax cake amounting to 21.4% of the original unsaponifiahles was removed by the filtration. 'lhis'calce was found by analysis to contain 18.0 to 21.4% sterols or approximately 11 to 12% of the sterols origially Pres n in he un ap ni c o The filtrate from the wax was treated with 2.5% by weight methanol and 0.5 by Weight water as a mixture and allowed to stand for several hours at 72 F. Thirty grams of sterols, i.e. 55.5% of those originally present in the unsaponifiables, was separated by filtration.

by weight of 90% aqueous methanol. The Slcrols were then precipitated by cooling to 5 C. and separated by ration The ld 9! s a -91 m e i l Oil and from the unsaponifiables are given in the Table I. All of the sterol fractions analyzed better than 96% sterols and contained from 18.6 to 29.5% stigmasterol.

As can be seen from the results. the waxes precipitated f om. the highe on entr t s f u sapo o to contain higher levels of sterols and this consequently led to lower sterol yields. The best procedure was to crystallize the wax from a solution'containing from 3 to 9% usssn n fiab s- Sart lples Band 9 in the table illustrate the difference i iqldr cas at d y m isture in the y1en4 dra s the c ys lis tion of 1 9 4 A can b 7 moisture led to a greater yield of wax and lower yield of sterols indicating that the presence of water tends to cause the sterols to precipitate in the wax fraction.

Table I Oondltlons tor Ylcld of Wax Condltlons tor Ylold 01 Stcrols Orystulllzlng Wax Based Upon Bterol Qrystulllzlng Sterols Based Upon Sample No. opt vtant 0 MI Cone, Temp, Unsttp. Oil, Percent Cone, 'Iemp., Unsnp., 011, Percent 0. Percent Percent Percent 0. Percent Percent 15.0 84.4 8.05 48.6 10.4 b 14.6 3.41 16. 0 a0 34. 4 8. 05 48. 6 30. 0 b 16. 8 3. 60 10.0 16 37.0 8.66 18.0 5 30.8 7. 20 7.6 16 35.0 8.20 22.8 B 28.8 0.68 7.0 20 16.3 3.68 9.0 25.0 15 36.0 0.1 6.3 I) 23. 0 5. 52 10. 8 l8. 0 10 22. ll 6.17 6. 0 lb 20. 8 6. 82 32-33 I). 7 5 34. 0 7. 84 8. 0 16 W. 9 4.8 16. 0 22. 0 6 l0. 7 0. so its 28.6 0.0 20.0 a 30.0 an

: glrltsgpgnlnnble matter.

The filtrate from the sterols on evaporation to about one-third its original volume and on cooling to 0' C. gave a secondcrop of wax amounting to 6.6% of the original unsaponifiables. This material analyzed 11% sterols. Thus 2.1% of the stcrols in the original unsaponfiables was lost in this fraction and in the two wax fractions only 13-14% of the sterols content was lost. The filtrate from this second wax fraction on treatment with 2.5% .by weight methanol and 0.5% by weight water gave a second crop of sterols, (9.7 gms.), which represcntcd 18% .of those originally present in the unsaponifiable fraction. in the two crops of storols the yield was 73.5% of the analyzed sterol content of the unsaponifiables which represented a 9% yield from, the original cane oil.

80th crops of sterols contained better than 98% sterols as determined by precipitation of the insoluble digitonin complex.

EXAMPLE IV This example illustrates the effect of the concentration of the original unsaponifiablea in'the ethylene dichloride solution upon the yields .of wax separated. the rterol content of the .wax and the final yields of crystalline lterplpwhichrnay be obtained by the use of this invention.

The unutponifiahle traction used in this experiment was nroparcd {tom a .cane oil which analyzed 22.3% on laponifinbles and 12.8% :tcrolr.

Samples of this unraponlflable material were dissolved in sullloiont ethylene dichloride to dissolve the entire product durum-temperature and filtered to remove traces of insoluble soaps. The filtrates were then concentrated or diluted with dry ethylene dichloride -to the levels indicated in Table l and cooled to the temperatures indiouted. The .waxea which s parated were removed by filtration and analyzed for lteroll. The yields and annlym are indicated in Table 1.

After the anus were removed the filtrates were conoentmod to the devcls indicated and treated with 4% tlons except No. 0 were tree of water when the war was erystalltmd out.

EXAMPLE V A tall oil residue resulting from the removal of substantially all of the fatty acids from tall oil and having an acid number of 0.7, a saponification value of 74.8 and containing 61.5% by weight unsaponifiable matter was used in this example.

Two hundred grams of residue were saponified by refluxing with 220 grams of 90% aqueous methanol containing 19.4 grams of NaOH for one hour. The resulting raponification mixture was diluted with 580 grams of warm water to yield a mixture of 60 parts water, 20 parts methano and 20 parts residue.

The diluted mixture was a thick cloudy honey-like solution, and was divided into two equal portions, one of these (A) was extracted with ethylene dichloride without further treatment, .the other portion (B) was diluted with l00 grams of methanol and 300 grams of water to give a final composition of water, methanol, and residue of 66, 22 and 11, respectively.

Both portions were extracted with three 600-700 ml. portions of ethylene dichloride and the extracts were washed twice with water containing 20% methanol. No cmulsons were encountered in the ethylene dichloride extractions providing the temperature was maintained at -60 C.

The ethylene dichloride extracts were evaporated and dried under vacuum with steam. Portion (A) yielded 61.1 grams ot-unsaponifiables and (B) 65.3 grams.

in order to separate the wax alcohols, the unsaponiiiables were dissolved in dry ethylene dichloride, portion (A) to a 7.5% solution and (B) to a 10% solution cooled to 3.5 C. for 3 hour: and filtered to separate the waxy solids which after drying weighed 9.8 grams and 11.4 grams. respectively. Since the solids from above contained considerable lterols. i.c., about sterols by digitonln analysis, the combined waxes were dissoltted in ethylene dichloride (4% solo.) and on cooling to room temperature yielded 5.5 grams of wax melting at -74 7. .C. The filtrate on treatment with 0.4% by weight water and 3.0% by weight'methanol' and cooling to C. for 3 hours yielded a crude mixture of sterols.-

The original ethylene dichloride, filtrates from portions A and B, containing the major portions of the sterols were concentrated to and 15% solids, respectiv y- Four percent by weight of 90% aqueous methanol was added to each solution and they were then held at 5 C. for several hours to out the hydrated sterols. The'yields for pc 'ons- A and B were 14.5 and 17.0 grams, r'espectively. A

The filtrates from the -first crops of sterols on concentration to solids solution yielded additional crops 6i sterols. i.e.,-' (Al-#14 and (B) =1.4 grams. Thus, the totalyield" of sterols fr'omthe two portions ('l 6.9' gni. 18.4 gm.) was}17.7% of-theoriginal200 When thes'terolsfronr portion A and B above were recrystallized'from ethylene-dichloride (10% solution) using 2% Superfiltrol, they gave 90% yieldspf pure white sterols 137-139 0.).

w'o' hundred l eaje Jail residue d r in Example V was saponified in 250 ;grams of 80% aqueou'sinethanolcontaining 12.8 :grams' of NaOH (20% excess) .by refluxing for one hour.- The mixture was diluted with 550-grams ofwater .to. yield a soap solution containing 60 parts water, 20 parts methanol-and 20 parts residue.

.'- The soap solution was ethylene dichlo- The unsaponifiable was 8 and cooled to 35 F. to yield a crop of sterols which, after washing with cold. ethylene dichloride and drying, amounted to 15.8% of the unsaponifiable fraction. A second crop of sterols increasing the yield-to 17.9% was obtained by concentrating and cooling the filtrate from the first crop. The yield based on the original unsaponified residue was 4.65%. The sterols melted in the range of 135-137 C.

Y EXAMPLE VIII- I Example VII was repeated, except that the wax was precipitated by chilling a 7.5% solution of the unsaponifiables. The yield of wax in this case was 3.45% and the yield of sterols 17.1% based on the unsaponifiables used. EXAMPLE IX A tall oil residue obtained by distillingcrude tall oil fatty acids was saponified and extractedwithethylene dichloride as described in Example VII. The yield of unsaponifiable was 24.3% of the tall oil residue. This material analyzed 34.8% sterols.

dissolved in dry ethylene dichloride to make a v7.5% solution. This solution was ride and the extracts were ,washed inflthe same manner as the fraction in Example v. eoneen- 1 trated to a level of 5% solids withaccompanying removal of water. 'Ooolingt60 5"CZ (overm"'gh o'pruuueed'lss' grams of a wax alcohol;rich fraction-.whichwas removed by filtration. Further. evaporation ,of the filtrate to 12% solids and the addition of4% by weight of 90% methanol .v rith-cooling-to 51 C. gave 36.6 grams of sterols (M.P. 136 137 5. C.);.. A second crop of 3.2 grams of sterols was obtained. by concentrating the filtrate',.to two-thirds the priginal volume and cooling. .The total .yield of sterols (39.8 grams) represented 19.9% of the original residue. The sterol fractions obtained in this example were-colorless and odorless and.analyzed 98.5-99. 5%

-The unsaponifiable filtrate from the sterols on removing the solvent weighed 77.5 grams and contained only 812% sterols. 4

The total sterols accounted for by isolation and by analysis of the unsaponifiablcs were 46.2 grams or 23.1% as compared with an-analyzed content of 26.2% in the original residue. v

Eighty-four pounds of a residue obtained by distilling crude tall oil fatty acids was saponified in an equal weight of 80% aqueous methanol using a 20% excess of sodium hydroxide vover that indicated by the saponification value .i.e., 132 of the residue. The mixture'was thenldiluted with an equal weight of water and extracted with ethylene dichloride. '2 a a 1.5.

The ethylene dichloride extracts were washed with water and evaporated to'yield 21.8 lbs.- ofunsa'ponifiable material which analyzed 26% sterols.-

A portion of the un'saponifiablematerialwas dissolved -in dry ethylene dichloride to make a 10% solution and .the hot solution was treated-with 2 percent Superfiltrol F.0.andfiltered.

The filtrate was cooled to F. to precipitate a waxy 'solid which was slurried and washed with cold (35 F.) ethylene dichloride and again .filtered.- 0n drying, the wax amounted to 3.7% of the original unsaponifiable fraction; Y o

; The filtrate and theabove wax were concentrated to a solution containing 20% solids. was treated with 4% by weightof 90% aqueous and the other to 35" F. to yields of wax were 1.41%

: total yields were 23-24%.

divided into 2 equal parts. One was cooled to 50 F.

precipitate wax fractions. The

and 1.85% respectively.

, The filtrates were concentrated to 20% solids, treated with 4% of 90% aqueous methanol and cooled to 35' F. The yields of sterols were 20.7%

and 20.4%, respectivcly, ,of the unsaponified matter. Second crops of slightly' lower purity were obtained by concentrating the filtrates; adding aqueous methanol, and cooling. The

Therefore; manymodifications and variations of the invention as hereinbefore set forth may be made without departing from the spirit and scope thereof, and therefore only such limitations should be imposed as are indicated inthe appendedclaims.--- r Now, therefore, we claim:

1. A- method of separating sterols, from a containing sterols and waxy constituents, which mixture was obtained from a member of the class consistingof tall oil and crude cane oil, which method comprisespreparing a solution of said mixture in ethylene dichloride, concentrating the solution and removing substantially all water present, cooling the solution to precipitate the waxy constituents while leaving the sterols dissolved, removing said waxy constituents, and then removing the sterols from the solution.

2. The method of claim 1 where the ethylene dichloride solution is cooled to0 to 25 C.

' solution.

3. The method of claim 1, where the solution is concentrated to a solids content of 312% unsaponifiable solids.

4. The method of obtaining sterols, free of waxy constituents, from a member selected from the class consisting of crude cane oil and crude tall oil, which method comprises preparinga solution of the oil in ethylene -dichloride, cooling said solution to precipitate waxy constituents, removing the waxy constituents, evaporating the ethylene dichloride from the remaining solution-to leave an oil, saponifying the resulting oil, diluting the reaction mixture with water, extracting said diluted reaction mixture with ethylene dichloride, acidifying the ethylene dichloride extract, concentrating the extract and -removing substantially all water present, cooling the ethylene dichloride extract to precipitate the waxy constituents while leaving the sterols dissolved, removing said waxy constituents, then removing the sterols from the s. A method of claim 4, where the ethylene dichloride solution is cooled to 0' to25' C. 6. The method of claim 4, where the extract is. con- 'ccntratcd tooontain 3--12%unsaponified solids.

7. A method of' obtaining' sterols, free of waxyaconstituents, from a member selected from the class consisting of crude cane oil and tall oil, which method comprises saponifying the 'oil, diluting the reaction mixture with water, extracting the reaction mixture'with ethylene dichloride, acidifying the ethylene dichloride extract, concentrating the extract and removing substantially all water present, cooling the ethylene dichloride extracts to precipitate waxy constituents while leaving the sterols dissolved, removing the waxy constituents, and then removing the sterols from solution.

8. The method of claim 7, where the ethylene dichloride extracts are cooled to 0 to 25 C.

9. The method of claim 7, where the extract is concentrated to a solids content of 33-12% unsaponifiablc solids.

References Cited in the file of this patent UNITED STATES PATENTS 2,191,260 Porsche Feb, 20, 1940 2,400,101 Buxton May 14, 1946 2,508,220 Buxton May 16, 1950 2,650,929 Hewett Sept. 1, 1953 2,715,639 Albrecht Aug. 16, 1955 2,729,656 Berry Jan. 3, 1956 Laquer Nov. 27, 1956

Claims (1)

1. A METHOD OF SEPARATING STEROLS, FROM A MIXTURE CONTAINING STEROLS AND WAXY CONSTITUENTS, WHICH MIXTURE WAS OBTAINED FROM A MEMBER OF THE CLASS CONSISTING OF TALL OIL AND CRUDE CANE OIL, WHICH METHOD COMPRISES PREPARING A SOLUTION OF SAID MIXTURE IN ETHYLENE DICHLORIDE, CONCENTRATING THE SOLUTION AND REMOVING SUBSTANTIALLY ALL WATER PRESENT, COOLING THE SOLUTION TO PRECIPITATE THE WAXY CONSTITUENTS WHILE LEAVING THE STEROLS DISSOLVED, REMOVING SAID WAXY CONSTITUENTS, AND THEN REMOVING THE STEROLS FROM THE SOLUTION.