US1823864A - Process of obtaining beryllium and aluminum compounds - Google Patents

Description

Sept. 15, 1931.

emo exmcnao 8 S 945:0 EXTRACTEO 8 8 c. B. SAWYER ET AL 1,823,864

PROCESS OF OBTAINING BERYLLIUM AND ALUMINUM COMPOUNDS Filed Oct. 14, 1930 EXTRACTION OF BEO H204 HEAT TREATED NEW HAMPSHIQE BEIZYL EXTRACTION OF 850 men RAW smYLmEw WITH SULPHUHIC ACID CF loo Au. SAMDLES QAPIOL'! AIR cameo VARIOUS CONCENTRATIONS EXTBACTIONS mos wrrn sa'ae. qo

suumumc m0 AT 236' 0. FOR 15! nouns.

70 a E 50 3 5 W 50 o I]; a 40 3 250 260 TEMPERATURE OF ACID TREATMENT FIG. 5

0 Z 4 6 B IO I2 rm: OF HEAT TREATMENT won: (nouns) FIG. 1

seo EXTIZACTED mom 552w. (NEW HAMPSHIRE) 46}; suwnumc ACID AT 25m #041 m nouas (mzzssua: TREATMENT) 6. 3. BY 64x 2 W ATTOQNEY an" 500' 100 300 q00 TEMPERATUQE OF 025 TREATMENT FIG. 2

Patented Sept. 15, 1931 UNITED STATES PATENT ol-"rlcs CHARLES B. SAWYER AND B ENGT KJELLGBEN, OI CLEVELAND, OHIO, ASBIGNORS TO THE BRUSH BERYLL'IUM COMPANY, OF OLEVELAHD, OHIO, A CORPORATION O]? OHIO PROCESS OF OBTAINING IBERYLLIUM AND ALUMINUM COMPOUNDS Application filed October 14, 1930, aerial No; 488,662, and in Canada January 6, 1921.

I have filed applications for this patent in Ca'In'ada, Serial No. 320,889, Jan. 6, 1927, and in Germany, Serial No. 129,473, J an. 31, 1927.

This invention relates to a process for the extraction of beryllium and uminum from ores containing them, such as beryl.

Heretoforethere has been no satisfactory method of recovering beryllium from the ore beryl because of the latters extremely high resistance to the action of most reagents. a One object of this invention is to rovide a method of treating beryl to make it more susce tible to the action of suitable reagents. A urther ob 'ect of the invention is to provide a relative y simple and cheap process for converting the beryllium and aluminum naturally occurring in the ore into soluble beryllium and aluminum salts from which the corres onding oxides may be formed.

Other oh'ects of the invention will be a (parent to t ose skilled in the art from t e escription of it hereinafter given.

In describing our process, reference will be made to the accompanying drawings which illustrate certain features of the process.

In the drawings, Fig. 1 is a series of curves showing the 'eifect of heat treatment of beryl at various temperatures uponiacid recovery treatment at approximately atmospheric pressure. p y

Fig. 2 is a curve and data showing the effect of heat treatment of beryl at various temperatures upon acid recovery treatment above atmospheric pressure.

Fig. 3 is a series of curves showing the effect of treatment under pressure of raw beryl with sulphuric acid of various concen- 40 trations at various temperatures (pressures).

Our invention is based pnmarily on the discovery that beryllium and aluminum occurring in beryl may be made susoe tible to the action of suitable reagents by su jecting the beryl to the action of heat in a manner to modify its physical structure and so render it more readily attacked by the reagent to be used.

The heat treatment of the beryl can be carried out at various temperatures. The

resulting modification of the ore begins at temperatures below 1000 C. and increases as the temperature of the treatment is increased. However, the increase in the effect of the treatment with increasein the temperature of the treatment is relatively slow below 1000 C. and becomes more rapid at temperatures above 1000 C; The maximum effect is secured by heating the ore to melting, at temperatures normally 9 from 1500 to 1600 0., and suchtreatment renders the ore readily attackable by sulphuric acid. However, when the beryl is heated at the more moderate temperature of sintering, such as about 1350 (1., and at still lower temperatures it is sufficiently modified. so that it is attached by certain reagents, such as sulphuric acid, althou h if the heat treatment of the ore is carri out at temperatures below its meltin point the treatment must be continued or a longer time than when the beryl is completely melted and also it may be necessary to treat the ore at a higher temperature with the reagent if the ore has not been heated to the point of is com lete melting. T e modification of the ore due to heating is not so pronounced if the ore is allowed to cool very slowly. Therefore, both as a matter of convenience and to ,secure the maximum efi'ect of the treatment, we re. idly cool the heated ore preferably by quenc ing i in a suitable medium, such as water. This es the ore in its modified state. It is possible to cool the ore in air fairly rapidl but in order to secure a maximum rate 0 .cooling we prefer to use a liquid quenching medium. The maximum reactivity of the ore is secured by quenching it from the molten state. The effect of quenching upon the reactivity is less 0 if the ore is heat treated at lower temperatures. We have found-that beryl may be heated as for example, in a recupefatlve oil fired furnace, or in an electric furnace, above the r fusion point so that it forms a free flowing molten liquid and, therefore, the heatin can be carried out if desired in a furnace 0 such character that the molten beryl will continuously run out directly into a quenching me- 199 dium such as water. Or if preferred, the beryl can be melted in a furnace and poured at intervals into the quenching medium.

After modification of the beryl by any-of the above methods, the beryl may be treated with a suitable reagent to attac the beryllium and aluminum content of the beryl. While it is possible to use hydrochloric acid, nitric acid, an aqueous solution of sodium hydroxide or other bases, and other reagents, to extract the aluminum and beryllium in beryl that has been modified by our improved process, we prefer to employ one of the mineral acids, and especially sulphuric acid, as the reagent.

To facilitate the reaction between the beryl and the reagent selected, said modified beryl can be comminuted, as in a suitable grinding mill. The said reagent is preferabl one which will render the aluminum and llium content of the beryl soluble, but which will leave the silica content thereof in insoluble condition. The said reagent may be mixed with said be:- 1 and heated to a tem- Eerature sufliciently igh and for a time sufciently long to render said aluminum and beryllium soluble, as by the conversion thereof to soluble salts.

It may be noted that in general the more complete the modification of the beryl, the greater is the reactivity thereof. Thus, the strength of reagent and the time and temperature required for the reaction between the beg:i and reagent varies with the degree of mo cation of the beryl, which in turn varies, within limits, with-the temperature to which the beryl has been heated, the length of heating and the rapidity of the cooling of said he if it is desired to specially cool the beryl. n this connection, it may be noted that the density of the beryl appears to be an indication of the degree 0 modification thereof. Thus the more complete the modification of the beryl, the lower appears to be the density thereof. For example, the density of one grade of crude beryl has been found to be 2.69, and be 1 that has been melted but not quenched as a density of 2.57. Beryl melted in a pot and poured into water was found to have a density of 2.49, while the beryl melted in a furnace and run constantly over a hot lip into water had a still lower density of 2.46.

As above indicated, we have found that sulphuric acid, preferably somewhat diluted, such as concentrations between 46 to 63 degrees Baum is a suitable rea eat to render soluble the aluminum and/0r ryllium content of be rl. Thus, for example sulphuric acid may mixed with modified beryl to an amount slightly greater than that theoretically required to react with the aluminum and beryllium and the mixtureheated in a suitable vessel, such as, for example, an open lead pot or even an iron pot. Thus for example, we have found that the reaction be tween the modified beryl and sulphuric acid may be substantially completed by heating for a relatively short time, such as an hour or less at substantially atmospheric pressure. It will be understood that the reaction between the beryl and sulphuric acid may be carried out by heating the reaction mixture for longer or shorter times, do udin in part upon the temperature emp oyed. TVe have'discovered that the temperature and pressure at which the treatment of the modified ore with the acid or other rea at is carried out are important factors a acting the degree of extraction of the beryllium and aluminum contents of the ore. Indeed the effect of increasin sure in treating the ore with sulphuric acid, for example, is so marked that the treatment under pressure may under some conditions be a major consideration in the practice of our process. Furthermore, we have found that theincreased activit secured by treatment under pressure holds true in the case of raw or unheated beryl as well as in the case of heat treated ore. Treatment of the ore under pressure can be carried out with the temperature and pressulphuric acid, for example, in a closed tubeor, on a larger scale, in a lead lined autoclave or other suitable container. At a later point in the description we shall refer further to the treatment under pressure in connection with the drawings.

By taking advantage of the differential reactivities of the beryllium and aluminum compounds as existing in the modified beryl and of the various factors affecting the activit of the sul huric acid in converting the bery 'um and a uminum compounds of such her I into soluble sulphates, the beryllium and aluminum may either be extracted successively or simultaneously, as desired. For example, if a melted beryl, such as is found in South Dakota, is treated with sulphuric acid of about the concentration of chamber acid and at a temperature of about 200 (3., a good extraction of the her llium from the treated beryl is obtained. ith the said acid at a higher temperature, such as 250 C. for instance, the aluminum is also attacked, and it will thus be seen that variation of the temperature afi'ords a method for the separate extraction of the beryllium and aluminum contained in the ori 'nal beryl. Beryls from other deposits may ave both the beryllium content and aluminum content rendered soluble even by the first of these two treatments and therefore the amount of action or the activity of the acid in attacking the beryllium and aluminum compounds of the beryl will have to be diminished if it be desired to extract the beryllium and aluminum successively, as will be more fully explained. And beryls from still other deposits, on the other hand, may need to have the activity of habits the acid increased, de ending upon the composition of thebery The ber 11mm and aluminum mayeitherbe extracte successifvely or simultaneously, as desired, depending upon the degree of modification of the beryl, the concentration of the acid used and t e tem rature and time of reaction between the aci and the comminuted beryl.

When the beryllium and aluminum contents of the beryl are attacked to form the soluble aluminum and beryllium sulphates, the silica is left as a silicic acid completely dehydrated if the temperature of treatment is sufliciently high.

The product of the reaction between the beryl and a suitablereagent, such as, for example, sulphuric acid, may be treated with water or other liquid, the soluble aluminum and beryllium com unds dissolved therein, the solutiomfiltered to remove insoluble ma-: terial andjxthe aluminum and beryllium compounds recovered from such filtrate, by methods hereinafter described.

Dependent on the composition of the natural beryl, there may be also considerable quantities of iron sulphate in the sulphate solution. After removin the aluminum and beryllium, a final mother 'quor with the iron content therein remains.

In carrying out our process, after treatment of the modified beryl with sulphuric I acid we prefer to extract'the sul hates with water from the sulphated material so as to make an aqueous solution of the sulphates. From this solution the aluminum sulphate maybe completely separated by converting it into an alum, for example, ammonia alum, by adding a suflicient amount of ammonium sulphate, and subsequently remoying the alum by crystallization. It has been known that a major portion of the aluminum can be separated from the other sulphates as an alum, but heretofore it has never been possible to secure a complete separation. According to the present invention a complete separation may be attained 'by eitherof two methods,

both of which are based on the discovery that an alum, such for example as ammonia alum or potassium alum, is substantially insoluble in an aqueous solution, of suitable concentration and temperature, containing a mixture of bezllium sulphate and an alkali sulphate, sue for example as ammonium sulphate or potassium sulphate.

A saturated solution of beryllium sulphate dissolves some ammonia aluin at room ternperature. If, however, ammonium sulphate is added the solubilit of ammonia alum in this solution rapidly ecreases and is practically zero at about 18 (3., when the amount of ammonium sul hate a proaches about 6% L of the wei ht 0 cr stalllne beryllium sul phate in so ution. I the beryllium sulphate solution is not saturated a greater amount of ammonium sulphate has to be added. Also if the temperature of the beryllium sulphate solution is increased, more ammonium sulphate has to be added. For practical purposes it is preferable to use an amount of ammonium sulphate equal to 10-20% of the weight of the crystalline beryllium sulphate present in order to secure a wider usable ran e of concentrations and temperatures.

fiery high percenta es of ammonium sulphate can also be used, but it is, of course, preferable to use as little ammonium sulphate as practically possible. If the amount of ammonium sul hate is less than about 6% of the weight 0 the crystalline beryllium sulphate the alummay still be completely separated by cooling the solution to temperatures lower than ordinary room temperatures.

One of the two separation methods referred to consists in separating the alum by adding to the sulphate solution obtained by leaching the sulphatized ore an excess of ammonium sulphate whereby the ammonia alum formed becomes substantially insoluble in the solution and the beryllium sulphate remains entirely soluble. The excess of ammonium sul phate used depends to some degree on the concentration of the sulphate solution. In order entirely to remove all the ammonia alum, it is preferable to carry out the crystallization in'such a way that also some beryllium sulphate is or stallized out together with the ammonia alum. After separating the ammonia alum by filtration or otherwise, the beryllium sulphate content of the alum may be washed out and the washngs returned to the aqueous sulphate solution obtained from the leaching of the ore. The

mother liquor obtained after separatin the alum contains practically all the bery ium sulphate together with the iron content of the ore. By evaporation and crystallization of the beryllium sulphate from this mother liquor most of the iron is left in the mother liquor and a crystalline beryllium sulphate containing very little iron obtained.

The other method of separating the alum consists in adding to the sulphate solution obtained by leaching the sulphated ore enough ammonium sulphate to form ammon'a alum and then crystallizing out beryllium sulphate and ammonia alum together. After separation of the mixed crystals these crystals are leached with a suitable solution containing beryllium sulphate and ammonium sulphate. Such a leaching solution may contain, for example, 250 ams of crystalline beryllium sulphate per liter anl fiO g'rams of ammonium sulphate per liter. A solution of this concentration is capable of extracting about 570 grams of beryllium sulphate per liter at 20 C. from a mixture of beryllium sulphate and alum without dissolving the alum. The leaching process is carried out by stirring the mixed crystals preferably at room temperature or lower temperatures with the leaching solution. By this treatment all of the beryllium sulphate crystals are dissolved and the ammonia alum crystals left. The ammonia alum is further separated from the solution by filtration or otherwise and the beryllium sulphate in the filtrate recovered by evaporation and crystallization. The remainingmother 1i uor containing ammonium and beryllium su phates ma then be used a ain for leaching purposes a ter proper dilution with water.

a It will be s'een that whichever of the two procedures for separating the alum is used there is involved essentially the use of a solution of beryllium sulphate and an alkali sulphate which contains an amount of the alkali sulphate suflicient to render the alum completely insoluble in the solution of the concentration and temperature employed.

In each of the above described methods of separating the aluminum content the beryllium suiplhate formed generally contains some iron.

is beryllium sulphate is purified by recrystallization.

In all of the crystallizing operations herein described in which iron is present it should preferably be in the ferrous state and such condition-can be insured b any ,well known method, such as the intro notion of sulphur dioxide or barium sulphide.

The iron which remains in the mother liq uor obtained from the crystallization of b ryllium sulphate in the first described method of separating the aluminum content -or from the crystallization'of the mixed crystale of beryllium sul hate and ammona alum in the second metho may be lar ely removed therefrom in any one of severa ways, such as, for example by further concentrationof the solution and .crystallizing out of ferrous ammonium sulphate. The final mother liquor remaining from the iron crystallization contains substantially all the excess free acid and is sufliciently reduced in iron content to permit its use as a reagent for subsequent treatment of additional beryl, or it may be added to the sulphate solution obtained by leaching the sulphatizedore;

If the sulphate solution obtained by leaching the ore contains much free acid, ammonia may be added instead of ammonium sulphate. It will thus be seen that by the use of ammonia the excess sulphuric acid may be recovered as ammonium sulphate and thereby utilined in the process for the formation of ammonia alum. 1

The beryllium sulphate produced by our above described method can be decomposed into sulphur trioxide and beryllium oxide by heating to temperatures such as 800 to 1000 C. The sulphur trioxide may be converted to sulphuric acid for use in the process. Also the ammonia alum roduced 1n the process me. be decomposed into ammonium sulphate an aluminum sulphate, for example, by the ammonia alum bemg recovered. The aluininum sulphate produced in this'manner may in turn e decomposed into aluminum oxide and sulphur trioxide in the same manner as the beryllium sulphate. If desired, the mixed crystals of beryllium sulphate and ammonia alum may be converted into the mixed oxides of her llium and aluminum.

An indicative of the modification of beryl by our method of heat treating the same, we have shown in Fig. 1 of the drawing a series of curves indicating the effect of the heat treatment of the beryl upon the recovery of the beryllium content by our method of treatment. the beryllium content, in terms of the percent of beryllium oxide extracted, is plotted vertically against the time of the heat treatment of the beryl, the curves representing heat treatments at the difierent temperatures. The extractions of the modified beryl were made with 100% excess of 63 B6. sulphuric acid at 236 C. in a closed tube, the time of the acid treatment in each case being 15 hours. i

It will be observed onreferring to the curves that for this particular acid treatment the effect of heat treatment at 1000 C. u on the reactivity of the beryl was measurable ut relatively small. The eflect of the heat treatment at 1200 C. is still reater but the increase is not'marked. owever, when the heat treatment of the beryl is carried out at 1300 C. the recovery of the beryllium con:

tent is markedly increased, being nearly It will be noted that the recovery of p in turn is fully double that for the treatment at 1300 C. The data for the treatment at 15.00" C. is not so full but it will be noted that the increasein the recovery for the treatment at 1500 C. is markedly reater than that for 1400 (1.; and, finally, w en the ore was heated to the melting point and rapidly cooled in air the recovery was'increased to about eighty percent. By quenchin' the melted ore in water we have been ab e to attain a beryllium recovery of nearly 99%.

In Fig. 20f the drawings we resent data which indicate the efi'cct both 0 acid treatment under pressure andoi the heat treatment of the ore. This figure represents treatment of heat treated beryl with 46 B6. sulphuric acid at 251 C. (approximately 118 C. above the boiling point'of the acid) for 19'hours, and the percent of beryllium oxide extracted is plotted "vertically against a-one-hour heat treatment *of the ore at various temperatures. On comparing Fig. 2 with Fig. 1 it will be observed that the effect of the acid treatment of the are under pressure is to verysubstantially increase the extraction of beryllium oxide both from the raw ore and the heat treated ore. Even in the case of the raw ore the extraction is increased by the use of pressure from a very few percent to upwards of 50%. Also, it will be seen from a comparison of these two figures that the increase in the recovery of beryllium oxide from the ore incident to the increase in the temperature of the ore treatment is even more marked when the acid treatment is carried out under substantial pressure than when it is carried out at atmospheric pressure. From Fig. 2 it will be noted that a heat treatment of the ore as low as 935 gives the relatively high extraction of beryllium oxide of 76+ if the heat treatment of the ore is sufliciently prolonged, thus bringing out the influence of the time of heat treatment of the ore.

Considering both Figs. 1 and 2, it will be seen, as we pointed out earlier in the description, that while the heat treatment of the ore at temperatures below 1000 C. somewhat increases the reactivity of the ore, the rate of increase of the reactivity with increase of temperature up to about 1000 C. is relatively slight while heat treatment of the ore at temperatures above about 1000 C. increases its reactivity more and more rapidly up to the maximum efi'ect which is secured at the melting temperature of the ore.

Fig. 3 of the drawing is a series of curves representing extraction of beryllium oxide from raw beryl by 17 hours treatment with sulphuric acid of various concentrations at various temperatures above the boiling point of the acid, the treatments being carried out in a closed container. The extraction of beryllium oxide is plotted vertically against the temperature of the acid treatment and each curve represents a particular acid concentration. This series of curves shows that the beryllium oxide extraction increases with decrease in the concentration of the acid and with increase in the temperature of the acid treatment, both of which factors correspond to increase in the pressure. The data in this figure also shows the effect of the time factor in the acid treatment, the extraction of beryllium oxide by 46 B. acid at 265 C. being increased from about 66% to about 76% by prolonging the acid treatment from 17 hours to 46 hours.

The beryl found in diiferent deposits varies somewhat in composition and we have found that the differences in the composition of the ore cause it to behave somwhat diflerentlv in the application of our improved method. Our study of ores of different composition has resulted in the discovery that it is possible, in the case at least of some of the ores, to improve their adaptability to our process by the addition to them of suitable substances. In particular, we have found that by the addition to the beryl of suitable substances in very small amounts it is possible, without interfering with the successful carrying out of the various steps of our process, to ver substantially lower the meltlng point of t e ore and thus permit a modification of the ore b our improved heat treatment at a markedly ower temperature than would otherwise be possible, thus realizing substantial economic gains in the process.

Furthermore, we have found that by the addition of a suitable substance or substances it is possible to not only thus lower the melting point of the ore but also to increase the reactivity of the ore, in a manner which we do not fully understand but which we believe essentially involves a retardation of the recrystallization of the melted ore.

Among the substances which may be added to the ore for the purposes specified are compounds oxides for example, of iron, calcium and sodium. All of these substances when added to the ore in smallamounts have the effect of lowering its melting point and iron, for example, also has the marked added effect of increasing the reactivity of the ore when melted and quenched, this latter effect being due, we believe to a retarding efl'ect upon the recrystallization of the melted ore, thus insuring the preservation to a higher degree of the modifying eflect of the heat treatment. The addition to the ore of any one or more of the substances above mentioned obviously will not interfere with any of the several steps of our rocess of treatment. Two of the ores whic we have used one from New Ham shire and the other from South Dakota, will serve to illustrate the efl'ect of the composition of the ore which we have just been de- Of these two ores, that from South Dakota was found to have a lower melting point than that from New Hampshire but the latter ore, on the other hand, after melting and rapid cooling was found to have a higher reactiv1ty to the acid treatment. By the addition of a small amount of iron oxide to the South Dakota ore we found it possible to increase its reactivity to the acid treatment, as well as somewhat further lowering its melting point, thus illustrating the efl'ect of modifying the composition as above described.

As illustratin the character of our process we give the 0 owing specific example, in which sulphuric acid is employed as reagent:

100 lbs. of beryl, which has been melted and quenched as above explained and ground to pass a Tyler 200-mesh sieve, is mixed with 120 lbs. 63 B. sulphuric acid, which is about 10% excess of the acid. The mixture is then heated in an iron container. As soon as the acid becomes slightly warm the reaction starts, and the temperature increases rapidly. Steam and gases go ofi, and the mixture seems to boil. After about hour the reaction slows down. The container is then covered and heated up to 250300 C. for about 24 hours, to dehydrate the silica formed. After cooling, the white sulphated material is broken up in lumps and leached with water. The insoluble residue is separated by filtration and the filtrate concentrated to a specific gravity of about 1.32 at 20 C.

The filtrate or solution now has a volume of about 117 liters, and contains about:

35 grams BeO per liter 49 A1 0 per liter 3 F8203 per liter in the form of sulphates.

The extracted yield of beryllium oxide is about 90%.

In order to separate the aluminum from the beryllium, ammonium sulphate is added to the solution, and ammonia alum separated by crystallization. The solution above contains 5740 grams A1 0 as aluminum sulphate. It would require 7400 grams ammonium sulphate to form ammonia alum. However, about 25% excess ammonium sulphate. or 9400 grams, is used. It may be dissolved in waterto a saturated solution and added directly to the cold sulphate solution. The ammonia alum crystallizes quickly and is separated by filtration. The mother liquor has a volume of about 104 liters and a specific gravity of about 1.21 at 15 C.

It contains about:

33 grams BeO per liter .32 ALO, 2.9 c Z :c 19 i free (NHQ SO, per liter.

The acidity of the solution is 1.5 to 2.0 normal in sulphuric acid.

For removal of the last part of the aluminum present. this mother liquor is concentrated to a specific gravity of 1.32 at boiling temperature, or to a volume of about 60 liters, and then crystallized by cooling to room temperature. The crystals consisting of ammonia alum and some beryllium sulphate are separated by filtration. The filtrate is now free from aluminum according to test carried out by the 8-hydroxyquinoline separation method by Berg, as modified by Kolthotl' and Sandell (JournalAmerican Cbimical So ciety. 50, 1900 (1929) It has a specific gravity of about 1.30 at 20 C. and contains about:

73 grams BeO per liter and 10 F os i in the form of sulphates.

For separation of the beryllium from the iron the filtrate is concentrated to about 1.45- 1.46 specific gravity at boiling temperature,

nausea and the solution crystallized by cooling, hav ing preferably first reduced the iron with sulphur dioxide. The crystals formed contain 01% of Fe O By recrystallization of the beryllium sulphate formed the iron content of the crystals is only .002 to 003%. In other words, the beryllium sulphate is practically chemically pure.

It will be understood that the beryllium sulphate produced canbe treated in various known ways to convert the beryllium content to different forms. For example, the sulphate can be converted to beryllium oxide by heating it to drive off sulphur trioxide; and the beryllium oxide, in turn, can be converted into various other compounds such as fluorides and chlorides suitable for electrolysis.

As further illustrating the practice of our improved process, We give the following example using hydrochloric acid as reagent:

A suitable amount of beryl modified, as previously explained, by melting quenching and ground to pass a ZOO-mesh sieve. is mixed with concentrated hydrochloric acid largely in excess of the amount theoretically necessary to react with the silicates of the ore. WVe have found that an excess of 100% is suitable which is equivalent to a ratio of 4 cc. of the concentrated acid to one gram of beryl like that of the first example above given. i

The mixed beryl and acid when heated react to form a solution of beryllium, alumiumn and iron chlorides and with the heating conducted at 84 C. for about 19 hours the yield of beryllium chloride is approximately 66% and of the aluminum and iron chlorides combined approximately 67%.

The separation of the chlorides is effected by treatment of the solution in known ways. For example, the solution can be treated with hydrochloride acid gas at low temperatures to effect separation of the chlorides, as described by Gooeh in his Methods in Chemical Analysis, first edition, pages 214 to 216.

It is recognized that it is known to heat beryl with oxides of alkalis and alkaline earths and with magnesium oxide in order to decompose the beryl and render the formed materials soluble in sulphuric acid. It is also known to sinter or use aluminum silicates containing considerable amounts of alkalis, such as feldspar, in order to render them soluble in sulphuric acid. Furthermore, it is known to heat aluminum ores. such as clay, to temperatures below 900 C. to ren der.them more reactive to sulphuric acid. However, the present process is distinguished in that the heat treatment increases the reactivity of the beryl to reagents, such as sulphuric acid, by effecting a change in the physical structure of the ore and Without any substantial change in its chemical composition, and in that this increase in reactivity is secured in an ore which contains no and i significant amount of alkalis. The result, in the present process, is to make the ore beryl, heretofore considered highly resistant, subject to direct attack by reagents, such as sulphuric acid, which would not attack the nat ural beryl.

The present application constitutes a con tinuation in partof our earlier filed applications Serial No. 5169, filed January 27, 1925, and Serial No. 123,593, filed July 19, 1926. In the present application we do not claim the hereindisclosed method of treating the beryl with a reagent under superatmospheric pressure nor the addition of an oxide to the beryl to facilitate the modification thereof nor the methods of recovering the beryllium and aluminum from the ore after it has been treated with sulphuric acid or other reagent, these several methods or features and certain features incidental thereto being claimed in our copcnding application Serial No. 536,518, filed May 11, 1931, as a division of the present application.

To those skilled in the art it will be apparcut that our invention can be practiced with a variety of modifications and in various differing embodiments without departing from the spirit and scope thereof as defined in the appended claims.

What we claim is:

1. The process of extracting beryllium from beryl which comprises modifying the physical structure of the beryl by heating it at a temperature above 1000 C. and thereby increaslng its reactivity without the necessity of addition of reagents, and thereafter treating the modified beryl with a reagent adap ed to transform its beryllium content into a soluble form.

2. The process of extracting beryllium from beryl which comprises modifying the physical structure of the beryl by heating it at a temperature above 1000 C. and thereby increasing its reactivity without the necessity of addition of reagents, and thereafter treating the modified beryl with a mineral acid 0 a temperature and a concentration adapted to trans 'rm its beryllium content into a soluble form.

3. The process of extracting beryllium from beryl which comprises modifying the physical structure of the beryl by heating it at a temperature above 1000 C. and thereby increasing its reactivity without the necessity of addition of reagents, and thereafter treating the modified beryl with sulphuric acid of a. temperature and concentration to transform its beryllium content into beryllium sulphate.

4. The process of extracting beryllium from beryl which comprises modifying the physical structure of the beryl by heating it at a temperature above 1000 C. and thereby increasing its reactivity without the necessity of addition of reagents, rapidly cool ing the heated beryl to fix it in its modified form, and thereafter treating the modified product with a reagent adapted to transform its beryllium content into a soluble form.

5. The process of extracting beryllium from beryl which comprises melting the beryl, rapidly cooling the melted material and thereafter treating the same with a mineral acid of a temperature and concentration to transform the beryllium content of the beryl into a soluble form.

6. The process of extracting beryllium from beryl which comprises melting the beryl, rapidly cooling the melted material and thereafter treating the same with sulphuric acid of a temperature and concentration to transform the beryllium content of the beryl into beryllium sulphate.

7. In a process of extracting beryllium from beryl, the step which consists in heating the beryl without the addition of reagents at a temperature above 1000 C. to change its physical structure and thereby increase its reactivity to reagents.

8. In a process of extracting beryllium from beryl, the step which consists in melting the beryl.

9. In a process of extracting beryllium from beryl, the steps which consist in heating the beryl and rapidly cooling the same from its heated state. 10. In a process of extracting beryllium from beryl, the steps which consist in melting the beryl and rapidly cooling the same from its molten state.

11. The process of extracting beryllium from beryl, which comprises modifying the beryl by heating it sufiiciently, without the addition of reagents, to cause the beryllium to become soluble in sulphuric acid, and treating the thus modified beryl with sulphuric acid of a temperature and concentration to form a solution containing beryllium.

12. The process of extracting beryllium and aluminum from beryl which comprises modifying the beryl by heating it sufficiently, without the addition of reagents, to cause the beryllium and aluminum to become soluble in sulphuric acid, and treating the thus modified beryl with sulphuric acid of a temperature and concentration to form a solution containing beryllium and aluminum.

13. The process of extractin beryllium from beryl, which comprises Ireating the beryl sufficiently, without the addition of reagents, to modify it and thereby increase its reactivity to sulphuric acid and subjecting it to a sulphuric acid solution of a concentration of 63 Baum or less and at a temperature suflicient to dissolve substantially all of the beryllium.

14. The process of extracting beryllium and aluminum from beryl which comprises modifying the physical structure of the beryl by heating it, without the addition of reagents, and treating the modified beryl with a strong mineral acld of a concentration and at a temperature to dissolve the beryllium and aluminum and to leave the silica content of the beryl insoluble.

15. As a new and useful "product, beryl which has been heated at a temperature above 1000 C. and rapidly cooled and thereby had its reactivity substantially increased.

16. As a new aiid useful product, beryl which has been heated to the melting point and rapidly cooled.

In testimony whereof we hereunto afiix our signatures.

CHARLES H. SAWYER. BENGT KJELLGREN,

CHARLES E. SAWYER. BENGT KJELLGREN- CERTIFICATE or CORRECTION.

Patent No. 1,823,864. Granted September 15, I931, to

CHARLES B. SAWYER ET AL.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 1, line 1, strike out "i have filed applications for this patent" and insert instead We have filed applications; page 2, line 88, for "activity" read reactivity; page 3, line 100, for the misspelled word "washngs" read washings; page 4, line 77, for "An" read As; page '5, line 92, after "believe" insert a comma, page 6, line 100, for "84" read 84; and that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 15th day of December, A. D. 1931.

M. J. Moore. (Seal) Acting Commissioner of Patents.

CERTIFICATE OF CORRECTION.

Patent No. 1,823,864. Granted September 15, 1931, to

CHARLES B. SAWYER ET AL.

it is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 1, line 1, strike out "I have filed applications for this patent" and insert instead We have filed appiications; page 2, line 88, for "activity" read reactivity; page 3, line 100, for the misspelled word "washngs" read washings; page 4, line 77, for "An" read As; page 5, line 92, after "believe" insert a comma, page 6. line 100, for "84" read 84; and that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this l5th day of December, A. D. 1931.

M. J. Moore, (Seal) Acting Conunissioner of Patents.

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