PREPARATION of COPPER-BERYLLIUM ALLOYS from INDIAN BERYL by C

B. A. R. C.-794

GOVERNMENT OF INDIA ATOMIC ENERGY COMMISSION

PREPARATION OF COPPER-BERYLLIUM ALLOYS FROM INDIAN BERYL by C. M. Paul, B. P. Sharma, K. S. Sibba Rao, M. G. Rajadhyaksha and C. V. Sundaram Metallurgy Division

BHABHA ATOMIC RESEARCH CENTRB BOMBAY. INDIA 1975 B.A.Tt £.-794

GOVERfflff?*r OP INDIA ATOMIC ENERGY COMMISSIOH

OP COPPER-ffiRYLLIUM ALLOYS FROM INDIAN BEKYL

CM. tail, B.P. Shanua, K.S. Subba Rao, M.G. Rajaihyaksha and C.V. Sundaram Metallurgy

BHAEHA ATOTIC RESEARCH CEFTRE BOMBAY, TTOIA 1975 IWIS Subject Category * B?1

Descriptors >

BERYLLIUM ALLOYS

Cfo»FSH BASS ALLOYS

ALUMINIUM BASE AU.OYS

RP:RYI

BERYLLIOH OXIDES

BERYLLIUM FLUORIDES

FLOWSHEETS

CHEMICAL EREPAHATION

SIWTEKINC

SC5DIUM TVJORimS

MAGNESIUM

REDUCTION

HEALTH HAZARDS

TOXICIPY ABSTRACT

The paper present* the results of laboratory scale investigations on the preparation of oopper-beiylllum and aluminium beryllium master alloys starting from Indian beryl and adopting the fluoride process* The flowsheet involves.(1) oonvarsion of the Be-values in beryl Into water soluble sodi.ua beryllium fluoride, (?) preparation of beryllium hydroxide by alkali treatment of aqueous Na-BeF., (3) conversion of Be(OH). to (HH.)? BeF. by treatment with HH.HF-, (4) thermal decomposition of (HH,)_ BeF. to BeF. and (5) magneeiust reduction of BeF- (with the addition of copper/aluminium) to obtain beryllium alloys*

The method has been successfully employed for the preparation of Cu-Be •aster alloys containing about BjL Be and free of Kg on a 200 go scale. An overall Be-recovery of about 80# has been achieved* Al-8^ Be master alloys have also bean prepared by this oethod*

Toadoity and health hasards associated with Be are discussed

and the steps taken to ensure safe handling of Be are described* OF copraR-BEHrLLiui.t AI i.ara FMV INDIAN EJHY

CM. Paul, B.P. Shanna, K.S. Subba Rao, M.3. Rajadhyakaha and C.V, Sundaram

1. IfffROWCTION

Beryllium has oome to be recognised aa an important atrategic material with growing applications in the fields of electronics, spaoe-

? science, roaketery, nuclear power generation and aeronautics^ ' '*'s Tha major use of the metal is In tha form of copper-beryllium alloys (0«25-2.05$ Ba) whloh have ezoellent meohanioal and physical properties, namely oruperior fatigue and tensile strength, high thermal and electrical oonduotivity and good realotanoe to oorroeion and wear* Copper-beryllium alloys are extensively used in tha eleotronlo, electrical and other industries for the manufacture of springs, diaphragms, electrical oontacta, switches, non-sparking tools, dies, bearings, marine propellers etc*

Beryllium oxide has a high melting point (255O*C), large specific heat (O.JO oals/gm at 1OO*C), exceptional thermal conductivity, good thermal shook resistance and superior electrical resistance. It finds largest use in the eleotronlo industry aa a heat sink, and also in the manufacture of various ceramice.

The principal aouroe material for beryllium is the mineral beryl (3 BeO.AlJX,. 6S10,) whioh ooours in granite pagmatites and 1B recovered aa a co-product or by-produot with feldspar, sioa, lithium, tantalitc, oolumbite and oassiterite. The world production^ cf beryl (equivalent to 11$ BeO) has been estimated at about 8,000 tonnes in 1969, the main producer countries being Braail, India, U.S.S.B., Argentina, South Africa, Uganda and Rawanda. -2-

India has fairly large depoaita of beryl in Bihar, Bajaathan, Andhra Pradesh and Tamil Nadu, tha analysis of a typical grade being as follows!

BeO • 11*21 X

SiO2 - 63*66 X

A12O, - 18*60 X

fe2Oj - 2*29 X CaO - 0.45 X

mgO - 0*28 X

0*1} X

Considering the raw material resouroee in the oountry and the present and projeoted indigenous requirement of Cu-Be alloys, Be-oatal and beryllium oompounda in the electronic and eleotrloal industries, and space resesroh and nuclear energy programmss, a development programme on the preparation of beryllium metal and ita alloys and oompounda has bean undertaken at tha Bhabha Atomlo Reeearoh Centre, Bombay* The paper describes the development of the prooesa flow sheet for the preparation of BeO, Be?2 and Qu*£e and Al-Ba master alloya - atarting from beryl.

2* IR0CS33 SELECTION AITD PLOW SHEET The first steps in the extraction of beryllium from ita ore are

(1) treatment of the ore for the preparation of Be(Cti)2 and (2) conversion of Be(0fl)2 to a suitable intemediate followed by reduction to metal or alloy* For opening up the ore, 2 methods have found industrial aooaptanoe - (i) the sulphate process involving sulpburto aaid digestion of thermally treated (heating and ojoenohing) or chemically treated (fusion or sintering with alkali or alkaline earth oarbonates) V.1UM EEP.YL

JAW CRUSHING

BALL MILL GRIITMNO OVEH, SIZF. CLASSIFICATION WATER FILTRATION

DRYING SODIUM BILICOFLUORIDE f' 3ODA ASH MIXING

BRIQUETTINO

IRON JAW CRUSHING CRYOLITE -»l BALL MILL GRINDING WATKR RED MUD LEACHING (WASTE) FILTRATE FILTRA- CAUSTIC '*- (WASTB) 4-4 TIOH SODA FRECIPITATIOH FEEHIC —i SHBCIPI- •FILTRATE FILTRATION SOLFKATE TATION • I CALCINATION I : CAKE DISSOLUTION I CHALK POWDER BERYLLIUM OXIDB AWOHIUM HFUJORIDE FIIffRATION SOLUTION -53? BVAPORA- HYDROFLOO-* CRYSTALLISATION RIC ACID TI(m SCRUB- AMMONIUM ^ RESIDUE WATER —'- DECOMPOSITION FIODBUfi 1 FILTRATION i -#(WASTE) MAGNESIUM SUd WATER WATER (ALLOYING ADDITION REDUCTION LEACHING

BBBYLUUM BERYLLIUM PEBBLES MASTER ALLOY FLUORIDE t i SLUK^ MTTJ.TNG ALLOYING I OASTINOi DRYING : I COPPER BERYLLIUM VACUUM INDUCH ALD3Y {** 25? Be ) TION MELTING

ICASTING I i CAST BERYLLIUM METAL (99.556 Be) FIG.-1 i P10T SHBBT FOR THE PROIJUCTION OP BERYHiIUM MBTAIi AND ALLOYS. -4-

beryl followed by purification of the sulphate solution and

conversion to Be(0H)2» & (ii) the fluoride process involving sintering of beryl with

and N»2C0- followed by extraction of the Be-valuea by aqueous +r leaching of the sinter and oonvereion of - extract to Be(0H)2*

In the present investigations! the second method - the fluoride process - was ohosen for the following reasons • (1) Comparative ooat estimates available in the literature* •?* on the production of Be(OH). indicate that this route is the more eoonomioal* (2) The process does not involve high temperature operations* (3) The process is more selective in that only the beryllia content of beryl is attacked, leaving behind the major constituents •dklgO, and SiO. •- .fhioh account for about 90J& of the ore. There are two methods available for the preparation of Cu-Be master alloys starting from Be(OH). 1 (i) oarbothermio reduotion of BeO at temperatures above 2000*C in presenoe of copper in an arc furnace, and (11) magnesiothermio reduction of anhydrous BeF» (in presenoe of coppar). The method of magnesiothermic reduotion was preferred in the present investigations as i (1) Not only Cu-Be, but also Be-metal and Al-Be master alloys can be produced by this method, (2) The operation is comparatively dust-free and hence less hazardous, (3) The reduotion Is carried out at relatively lower temperatures (1300 - 14OO»C), -b-

(4) Cu-Be master alloy a containing 8?£ and more of beryllium can be prepared by this method (alloys containing upto only 4# Be are obtained by the first method)* The integrated flow sheet - shown in Pig* 1 - consists of the following main operations 1- (1) Conversion of the beryllium values in beryl to water soluble sodium beryllium fluoride, (2) Preparation of Be (OH), by HaOH treatment of Na-BeF. solution,

(3) Conversion of Be(OH)_ to (HH*^ BeFA ^ treatment with

(4) Thermal decompoeltion of(NH.)2 BeF. to (5) Production of Be-oetal and its alloys by magnesium reduction of BeF_.

3* SXPERIKKHTA1

(i) Conversion of the Be-values of beryl to water soluble double fluoride The opening up of beryl by sintering with sodium silioofluoride has been the subjeot of quite a few investigations in the past ' . The reaction proceeds aooording to the equation

3 BeO.AlgOj.6 SiO2 + 2

• A12O3 * C02

It has been reported that the addition of HSgCO^ to the charge reduces the consumption of NagSiFg and prevents the loss of fluorine as SiF^. Froa s, number of tests oarried out in the laboratory the optimum oonditions for maximum NeJBeF. reoovery were established as follows 1 -6-

1* Charge composition Beryl i HajSUg i NagCOj - 11.15 i 8.1 i 0*95 2. Sintering temperature • 700*0 % Sintering tine - 4 bra. Beryl containing about 11£ BeO (50-70 •••• al«e) waa first crushed

In a jaw oruaher to a alee of about 6 m.n4 and then vet ground In a ball mill to -200 mash powder. The powder after dr/lng waa mixed with NaJBlF* and Ha^CO, In the above ratio and ooopaoted at a preasure of 5 tons/sq. In* into 2,5 one dia x 2*5 ova long briquettes* The briquettee were then charged In salamander oruolblea and sintered In a vertioal tube eleotrlo reslatanoe furnace* The charge was then heated at the rate of 400*C/hr and aoaksd at the operating temperature of 700^0 for 4 hre* After ooolingf the briquettes were taken out and wet ground in a ball Bill to a aiae of about -200 nosh. The ground sinter (slurry) was then loaohed thriee, each tine for & hr with watei at room tempera* ture In lISI-3161 atainlesa ateel vessels keeping a fluo-aalt to water ratio of 1 • 7 in order to extract the soluble beryllium values* After eaoh leach, the solids were allowed to settle and the-solution is separated by deoaatation and filtration.

(il) Preparation of Be(OH)./BeO The oonversion of FagBeP. into BeO Involves (a) precipitating the Be-values as hydroxide using NaOH, (b) filtering and washing the hydroxide free of fluoride, and (o) drying and oaloinlng the hydroxide* -7-

Ourlng Initial investigations the hydroxide was prepared by the addition of stoiohlonetrio amount of NaOH Into a oold Na-BeF. solution containing about 4-5 gme of BeO/lltre. The hydroxide obtained by thla method was slimy and difficult to filter.

It has been reportedv ; that the hydroxide precipitated in a hot alkaline medium is granular end easily filterable. This has been confirmed In the laboratory eoale investigation*. Por best results the entire quantity of NaOR (20£ solution) was taken in an AISI J16 stainless steel vessel and treated with 2Oj6 of the stoiohionstrlo amount of Na^BeF. solution (4*5 gas of BeO/lltre) required for the reaction

HaJSeF. + 2 HaOH r Be(CH)> • 4 Hd?« The resultant alkalino eolation was heated to about 95-100#C and granular Be(OH). was precipitated from the solution, under continuous agitation, by the progressive addition of the remaining 80£ of the double fluoride solution* The slurry was then allowed to settle and the hydroxide was repulped and filtered to remove last traces of fluorides* The dried hydroxide was oaloined at 900-1000 *C In beryllia lined salanandnr (olay bonded graphite) orucible. The filtrate froii the hydroxide filtration contains valuable fluorine (as HaF) which is recovered and reoyoled In the prooess. It is mentioned In the literature that fluorine oan be reoovered as iron oryolite by the reaotion

6 Ha? + PeOlj •Jra5rsV6 * 3 HaC1

In the present work the filtrate (Ha?-25 gm/Utre) was aoldified to a pH of 4 with BS1 and treated at room temperature with stoiohlometrio amount of PeOl. (JO wtjt aqueous solution). The fluorine present In tne solution was reoovered as Insoluble N -0-

(iii) Preparation of anhydroua BeP^ from Bo (OH),.

Owing to the low volatility, high hygroaooploitqr and hydrolytio nature of Be?2, ita preparation in a pure and anhydroua fora toy tha fluorinatlon or hydrofluorlnation of the oxide la difficult* The aooepted method for the preparation of BeFg in the anhydroua and pure fora froa BeCGB), la baaed on the following re act lone

n 2 H Be(CB)2 • 2 FH4HP2 wA $#*i * 2°

(!O4)8BeF4 900*0 rBoF= • 2 HH^

The hydroxide oake was transferred Into high denalty polythene veeaele and agitated with atolohlometrlo amount of a 50jt eolation of HH.HFj for the formation of (HHjjBeF.. The (HH^gBeF. aolutlon formed was filtered and evaporated on water bath In high denalty polythene Teeaels to oxyetalllBe out the double fluoride salt* The oryatala were filtered out fro» the mother liquor, and dried before being fed to the subsequent decomposition stage* The deooBposltion of (NH^JeF. is an lntrloate step in the flow sheet for Be-oetal produotion on aooount of the corrosive nature of the molten salt *&d its tendency to excessive frothing during dsooBposl- tion* In the earlier preliminary investigations when gram quantities of the double fluoride were decomposed in batohas in platinum dish, it waa observed that the fluoride frothed excessively during decomposition resulting la the over-flow of the material. In order to overcome this problem, a graphite assembly was developed for the later investigations* The design of the deoomposltion aHOOmbly was nuoh as to porralt the continuous removal of the fluoride from the hot »ona, in order to eliminate frothing due to bubbling of NH.F vapours through molten BeP^. The assemoiy oonniated essentially of an induction heatod graphite tube (3* I.D., 1' long) kept inclined to the horizontnl. The double fluoride was fed at the top end of the tube and the molten BeF- flowing out through the other end was cast in a graphite mould. The by-produot NH.P was collected in a water oooled 4 AI3I-J16 stainless steel oondenaer conneoted at the top end of the graphite tube. (iv) Preparation of beryllium and its alloys by the magnesium reduction of BeF, Possible reducing agents for BeF~ are sodium, potassium, oaloium and magnesium. Out of these, sodium and potassium are more difficult to handle, while oaloium combines with Be to form a stable intermetallio -). Magnesium is however the most suitable metal for the reduction of BeF2<9,1O.11.i2)#

Ifagneeius in the fora of ahlps (25 mm x 25 as x 25 am) was taken In a graphite eruoible and tte base metal (Cu or 11) - also in the form of chips - (25 mm x 25 ma x 3,5 ma) was placed over it. Anhydrous BeFg was then charged over the metals and the oruoible was finally oovered with a graphite lid. The oruoible containing the oharge waa then heated In a 12 k.w* induotion furnace and held at 11OO*C for i hour for the completion of the reduotion reaotion* The temperature is finally raised to 1300-1400 *C and held for another i hour to Increase the fluidity of the MgFg slag and effect elag-oatJLl separation. During this period the oharge was kept agitated for 15 minutes with a graphite stlrrer and then oast in a oold -10-

graphite mould* After separating th« alley, unreaoted P«P? In th« slag was leached out with water and recovered for recycling* The alloys after ratnelting were oaat and their miorostructures examined* Similar experiments were also carried out for the preparation of Al-Be alloys* In the eleotronio and eleotrloal industries Cu-Be alloys containing about 2jC Be (with minor alloying additions like Co, Hi, Sn, in eto) are used in the fora of folia, wires and rods* The master alloy was therefore diluted with the required amount of copper in an induction furaaoe* The diluted alloy was then oaat in graphite moulds end hot rolled at 790*C after encasing In mild steel* The alloy waa then unsheathed and further oold rolled to si me with intermittent solution treatments at 79O*C for 1 hour*

4* BJBSULTS AITS DISCUSSION

(a) Sintering of beryl In a aeries of sintering experiments (on a scale of 1.25 gms of oontalned BeO)* the lnfluenoa of time and temperature on the reoovery of beryllium values of beryl as water soluble HagBeP. was examined (Table 1). It will be observed from the Table that a maximum reoovery of 96£ was obtained whan the sintering was oarried out at 700 *C for 4 hours* With ths inoreaae in sintering temperature, the maximum reoovery oame down owing probably to tha formation of insoluble Be-oompounds and also the dsoomposltlon of silloofluoride resulting in ths loss of fluorine as SIP.* On a soale of 50 gm of oontained BeO however marginal dsorease in the reooveries was observed - 94»9# and 92«5# for 700*0 (4 hours) and 750*0 (2 hours) respectively. • -n-

(b)

(c)

Plate 1 - Photomicrographs Of «8 cast master alloys of Cu-Be and Al-Be etched in aqueoue.1-3 «t* PeCl^ solution (a) Cu-3.9* Be; B.P.t x 200 (b) Cu-Qit Be; B.P.j x 560 (o) Cu-24.2.< Be and 1.25^ Mg; B.P.j x 100 (d) AX-9.5235 Be ftrtl 0.24# Hg; B.P.; x 560 -12-

("b) Preparation of anhydrous BoFg

Easily flltrable gramlar Ba(GB)2 oould ba pr*par»d by tha progressive addition of tha doubla fluorlda (HaJBeF-) aolatlon Into a hot alkaline solution containing atolohloaatrlo mount of NaOH and

Na2Be0. formed by the addition of 20£ of the total doubla fluorlda solution. The recovery was 97#» Fluorine preaent aa He? In tha hydroxide filtrate oould be recovered aa Na.FeFg at a reoovezy of about 90ft, Decomposition of (HH.)gBeF. waa atudled on both batoh and oontlououa prooesa. Batoh operations were rendered dlffloult on account of exceaelve frothing during daoonpoeition* Qontlnuoua decomposition of (HH.) JaF. was however found to work aatlafaotorlly and with the graphite aaeeably aet^up for the purpose it waa possible to obtain BeVg ** *he rate of 500 gn/hr at a recovery of 975*.

(o) Preparation of Be-alloya In tha preparation of Cu-Be alloy a, tha influence of exoess BeF, in tha charge on tha residual Mg«oontent In tha final alloy waa Invostlgated* The residual Hg-oontent In tha alloy waa found to daoreasa from 2jC to traces (Table 2) when tha Be?2 excess waa Taxied from 6£ to about 25# in tha ohaxga* Under the aaaa conditions with tha BeF* oontant of the charge fixed at 2596 exoeaa of the atoiohitnatrlo requirement, aa tha baxylllua loading in the final alloy waa inoreaaed froa about QfL to 2jf> (on tha basis of Mg-oharged) Ba-reoovery waa found to deorease fron 85»8 to 77.8JC (Table "> )• Residual Mg-oontent In tha alloys containing more than 6jt Ba haa bean found to ba around 0«5£. It oan ba seen that tha Be-^reoovery In -13-

the preparation of Cu-9jS Be alloy 1B only 85.P# even though the alloy Is almost free of reeitaal Mg. The following possible reaoone can be attributed to this - (1) oxidation and volatilisation of Mg during reduotlon. (2) reduced Be remaining in the slag without getting dissolved in solten copper and (3) carbide formation (by reaction with orucible material) and oxidation of rwduoed Be. After recovering the unreacted BeF_ from the sl*^ by aqueous leaohing the Be-reooveries based on beryl and BAF. were found to be about and 9Oj6 respectively in the preparation of 9f> Be master alloys* The higher beryllium recovery observed in the preparation of the 8# alloy oan be attributed to the better Blag-metal separation resulting from the larger difference in the densities of the alloy and the slag* It oan also be observed froo the photo-miorographs (Plate 1 ) that the 8$ alloy is more uniform in composition as compared to the 2% alloy* This is possibly due to the eutectoid reaction that takes place in this composition range* In view of the above, the preparation of &fd Be-maater alloy appears to be more attractive for commercial exploitation* By employing similar techniques it was possible to prepare Al-Be master alloys containing about 8# Be and 1.2J» residual magnesium on a 100 ga soale at a recovery of 90£ (on the basis of Kg charged) by the

reduotlon of BeF2 (taken 25$ excess) with Mg in presence of Al at 1100-1400*0, The possibility of preparation of copper-beryllium alloys at •uoh lower temperature with the incorporation of magnesium chloride flux in the charge was examined and it was possible to obtain alloys analysing about 8£ Be and free of magnesium at a recovery of B4.5J& by reduotlon of a -14- oharge oontalning 25$ exoeas BeP and HgClg (MgFj i MgClg * * 1OOO *C for | hour. In this oaoa the selective recovery of unxeaoted BuP. from the slag by water leaohing la not possible as both UgCl, and BeF» are soluble in water* However, Be oan be selectively preolpitated as Be(GB)2 and recovered, by treataent of the leaoh liquor with WH.OH.

In the preparation of Al-Se alloys with a oharge oontalning

100 eas of Al, HgCl2 flu, (Mg?2 • MgClg i i 1ii), 2# «xoe8a BeP? and Mg adjusted to give 9# Be loading in the final alloy, as the reduction teoperature «aa lnoreased froa 1000*C to IJQO'C the Be-loading inoreaaad from 4J( to about 8^ and the Be-reoovery (on the basie of Mg-«harged) in the alloy froa 41 to 9O.5?t. This is attributed to the inoreaso in the liquid solubility of Be in il with temperature,

(d) Fabrication of Cu-Be allccr strips A 12 SB thiok oast alloy oontalning about 1.6^ Be and 0.5$ Co was rolled to a final thlokneas of 0*216 am. The alloy encaaed in mild steel was first hot rolled at 790*C to a thlokneas of 3 ma, unsheathed and further cold rolled to the final thiokneaa* luring oold work when the hardness roes to 200 V.P.I,, it was solution treated (79O*C for 1 hour) prior to further oold working* The sheet on age-hardening gave a hardness of 270 V«PVB*

5. TOKXCITT AND HAHBLIBG OF BBRTUIIIM

Berylliun and its oompounds are ottrenely toxlo and if deposited in the body, especially in lungs, oause extensive local damage. When deposited in lungs they oause reduction in respiratory oapaoity and -15-

«eneral debility (beryllloBls) terminating in tuberouloeis or daath in severe exposure•• In oase of skin contamination severe skin oloers and granule**, are observed particularly on hands and face. 1 1 1 In view of this, adequate precautions' 3» *» 5) ^^ ^9n taken in the laboratory while handling beryllium and beryllium compounds. The laboratory oonelets of two rooms (each 20* x 20* floor area and 12' height) for tho handling of beryllium, and a ohange room (10* x 20' floor area and 12* height) all located at one end of the top most floor (3rd floor) of a building. The walls and roof of the laboratory are epoxy painted to minimise accumulation of powder and the floors are oovered with FTC tiles to facilitate easy decontamination. All operations involving handling of berylliua compounds* have been carried out under fuaehoods and inside glove boxes connected to a common ventilation gystems. The laboratory is equipped with 6 laboratory type fume hoods (4V x 2£* area }£• height) and a special walking type fume hood (10* x 5» area x 10* height) all having glass shutters, a oonopy hood (2* x 21) and a glove box (31 x 5* area x 5* height)* The change room accommodates a washing machine (for the laundry of work olothss) an emergency shower and raoks and store-wells for keeping protective wears and olothings* The laboratory is eonneoted to a ventilation system (located on the terrace) which provides an air-velooity greater than 150 ft/mln at all hood openings and the laboratory air is passed through a system of soughing and absolute filters assembled In a filter house, before letting out into the atmosphere. The air discharge rate is 250 m'/min

* Of tht compounds of beryllium.beryl is non-toxic and hence a facility existing outBide tht laboratory (in the Ore Dressing Seotion of the Metallurgy Division) has been mads use of for the crushing and grinding of beryl. -16-

which haa been achieved by means of a centrifugal blower having a dleoharge head of 150 mm of water. This also provides about 30 air ohangea per hour in the laboratory. Samples of in-plant and envirenmental air are taken periodically to determine the concentration of beryllium. The daily average ln^plant air ooncentratlon of beryllium haa been maintained at leaa than 2 mlorograms per a while the environmental contamination haa not been allowed to exoaed 0*01 micrograma per m , in aocordanoe with Health Physios Regulations. 2 a surfaoe contamination toleranoe level of 10 mlorograma per m haa been adhered to, Stepa have been taken to ensure that the effluents discharged into publio atreama do not have a beryllium ooncentratlon exceeding 1 ppnu In view of the extreme toxicity of beryllium, the diapoaal of wastes from beryllium industry has assumed greater Blgnifionnoe. In the laboratory the solid wastes sealed in polythene bogs and packed In mild steel drums are disposed of by ground burial* The liquid wastes on the other hand, after the removal of Be-values by chemical treatment are dlaoharged to oommon drains at safe discharge levels (1 ppffl)* A thorough house keeping routine haa been strictly enforced for the protection of personnel and to limit the spread of contamination* The entry and exit to the laboratory la strictly through the ohange room whioh la separated from the main laboratory by means of a barrier* All the operational staff in the laboratory are provided with over-coat a, gloves, over-shoes and respirators* Vacuum oleaning and wst mopping are employed to reduce the dust level in the laboratory* Laboratory coats and over shoes are changed once in three daya and laundered in the Trashing maohlne Bat up for the purpose* -17-

A striot medical supervision has been kept on all working personnel. Bnch worker Is examined for body contamination by urine

analysis* An initial sftdical examination and six-monthly chest X-rays

screenings, vital oapacity teats and weight checks have been conducted

on all personnel working in the laboratory.

6 • COHCWSIOIf

The produotion of Cu-SjG Be master alloys starting from Indian beryl has been successfully demonstrated on a laboratory scale adopting

• flowsheet that incorporates (i) opening up of beryl by the silico-

fluorlde route* and (il) preparation of master alloys by the magneciothermio

reduction of BeP« in presence of oopper. The overall beryllium recovery

has been observed to be around «#.

Cu*<*£ Be alloy shapes required in the electronic industry have

been suooessfully prepared by dilution of the master alloy followed by

rolling* Suoh shapes have been tested by the actual users and found

aooeptable.

7* AOKHOfLBDOBJERTS

The authors wish to express their sinoere thanks to Dr. V.K,

Xoortby, Haad, Mrtalluxigy Division, B.A*R.C., for his valuable suggestions

and for the keen interest «vlnoed by him in the projeot. The authors are

particularly indebted to Dr. M. Shankar Das and Dr. C.9.P. Iyer of the

analytical Chemistry Division, B.A.H.C., for getting the various samples

analysed. Our •psolftl thanks are also due to Dr. A.K. Ganguly, Direotor,

Chmioal Group and Shri S.D. Soman, Head, Health Rxysics Division for their

valuable guidance in the setting up of the Beryllium Laboratory and

organising the regular Health Ihysice surveillance programme. -I-1-

RBFEREHCSS

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2. Proceedings of the Beryllium Conference, Vol.1, NMAB-272, National Academy of Sclenoea - National Academy of Engineering, Washington, D,C, (July 1970).

3« Beryllium Technology, 2, Gordon and Breach, Solenoe Publishers, Inc., New York, (W)

4. Minerals Year Book, 1-2, U.S. Govt. Printing Office, Washington, (1971).

5» D»A. Everest, B. Napier and R.A. Wells, Bull* Inst. Min. Met., 74» (1965), 869.

6, G.B. Darwin and J»H. Buddery, Beryllium, Butterworths Soientifio Publication, London, (i960).

7. Extraction and Refining of the Rarer Metals, The Institution of Mining and Metallurgy, London, (1957), 310.

8* D.W. White and J«S, Burke, The Metal Beryllium, The American Society for Metals, Ohio (1955).

9, Advances in Extractive Metallurgy, Blsevier Publishing Co. ltd., Essex, (1967), 551-71.

10. T. Banerjee and P.3. Chakravarti, Symposium on Rare Metals, The Indian Institute of Metals, Calcutta, (1957), 124*

11* H.A, Slomen, C.B. Sawyer, Field Information Agency, Technical, U.S. Group Control Counoil for Germany Final Report No* 522. British Intelligence Objective Sub-£ommittee, London (1946;*

12* H.H. Hausner, Beryllium, Its Metallurgy and Properties, University of California Press, Berkeley, (1^)

15. SJ>« Soman, P.H« Kamath, B.A.R.O* Report, A«S.B,T«/H«P./SM/7, (1960),

14, H, Stokinger, Beryllium Its Industrial Hygiene Aspeots, Academio Press, New York, (1966)*

15* A. Bamamurthy, S«B« Tedak, A.J. Aga and K.S* Somayaji, National Conference on Bnvironmental Pollution and XII Annual Conference of Indian Association of Occupational Health, Bombay (1971)* TaMe 1

INFLUENCE OF SINTERING TIME AND TEMFBRATURE ON BERYLLIUM R3C0V.JE7

Charge composition i Beryl (11.21$ BeO) i RaoSiF, i fla-CO-

i i 11.15 i 8.1 i 0.95

Scale of operation i 1«25 go of contained BeO

Sintering Recovery of BeO * tine hra r

Sintering i 1 -13P 2 3 4 5 temperatureil

700 55-5 .7 88.0 91*4 95.4 96.0 94.4 750 65.8 85.'6 86.7 93.8 93.1 92.0 78.7 800 69.8 86.6 85.6 Table 2

INFLUENCE OF EXCESS T3eP? ON THE RS3ID0AI Mg-CONTRNT IN THS AI10Y

Conditions* Scale of operation 200 gm of copper Reduction temperature « 1100*0

Duration i hour Final temperature 1400*0

Maximum Excess BeP- possible charged Alloy ooaapoaition Be-loading based on % Mg charged Be $ • Mg£

9.00 25 7.93 Traces 10.86 15 9.45 1.49 10.86 10 9.42 1.52 10.86 6 2.02 Table

IHFLnENCE OF Be-LOADING ON Be-BECOVERY

Conditional

Scale of operation ~ 200 cm of oopper

BePj - 25?o excess over etoichiometric

Heduotlon temperature - 11OO°C

Duration - £ hour

Final temperature - 1400*0

Maximum Alloy Alloy composition Be-recovery possible Rooovery based on Be-loadlng Be $ Mg-charged based on Kg-oherged

9 97.5 7.93 Traces 85.8 15 88.1 13.93 0.61 81 «,3 20 87.5 17.90 0.60 78.2 25 85.4 22.79 0.51 77.8