Notes on the precipitation of gold from cyanide solution

Transcription

1 Scholars' Mine Bachelors Theses Student Research & Creative Works 1910 Notes on the precipitation of gold from cyanide solution Charles Adrian Burdick Harry Wade Connelly Follow this and additional works at: Part of the Mining Engineering Commons Department: Mining and Nuclear Engineering Recommended Citation Burdick, Charles Adrian and Connelly, Harry Wade, Notes on the precipitation of gold from cyanide solution (1910). Bachelors Theses This Thesis - Open Access is brought to you for free and open access by Scholars' Mine. It has been accepted for inclusion in Bachelors Theses by an authorized administrator of Scholars' Mine. This work is protected by U. S. Copyright Law. Unauthorized use including reproduction for redistribution requires the permission of the copyright holder. For more information, please contact scholarsmine@mst.edu.

2 A The sis ror the Degree o BACHELOR of' SOIENCF.; IN 1:1 I N I N G ENG I NEE R I N G. T '? r NOTES ON OF GOLD FROM THE PRECIPITATION CYANIDE SOLUTION. C. A. Burdick. H. W.. Connelly'. Approved

3 Notes on the Precipitation of Gold From. Cya..'lide Solu t1ons. This work was to determine the Potassium Cyanide and tile Zinc oonsumed in the precipitation of Gold rro cyanide solutions by zinc dust. Writers on the zino dust method give much deta.ill but ami t data. on the consumption of potaasiujn cyanide and of zinc in tho process. JUlian and Smart in their book, Oymliding of Gold and Silver Ores, Bay that in the treating of 15 tons or strong cyanide solution, oarrying 6.0 oz. gold par ton 19 lb. zinc dust were used, and for 14 tone of weak solution, 17 lb. of zino duet were used, making 36 lb. of zino dust added for 29 tons of solution or 1.24 lb. zinc duet per ton of solution. They do not say whether there 'a.s zina in the preci.pita.te. The above solutions were reduoed to 2 dwt. of gold plue silver per ton of solution. For our work the preoipitation was in each 0&S6 made in 300 c.c. of solution. A gold cyanide solution was used which contained per o.e mgm. of gold ( oz. per ton o solution) and O.0012 KON. To obtain or eaoh test the desired varying amounts of

4 2 gold and of potassium oyanide, a solution, with no gold, but oontaining 7.3 KeN was added to the above mentioned gold solution as required. In the first experiment the amount of zinc duet and of potas8in cyanide was kept constant while the gold was varied from 1.00 oz. per ton to oz. per ton of solution. The Bo1ution contained O.20 of potassium oyanide and 0.18 lb. of zino dust was used par ton of solution. The zino consumed was 0.19 to 0.23 lb. per ton of solution. The zinc consumed inoreased slightly with the increase of gold in the solution. By plotting the oz. gold per ton of solution and tho pounds of zino ooneumad we get & straight line. See curve No. The KON consumed ranges from 0.62 to O.AO lb. per ton of solution. Plotting the potassium cyanide against the gold we get a straight line. See ourve No. The percentage gold recovered rapidly Increased until the solution oontaining 0.30 oz. of' gold per ton of solution was reached. At this point the recovery under our condition is a maximum (77.%) From here the recovery decreaded slightly as the solutions lncreass 1n gold. See ourva No. In the seoond experiment the amount of zino and of gold in the _olution are kept constant, whila the amount of potassium oyanide was va.ried from a 1.OO

5 3 solution to a O.005 solution. The gold solution was 0.50 oz. gold par ton and lb. of' zino duet was used per ton or solution. The gold extracted increased rapidly up to the O.05 KeN solution and it remained oonstant at 78% as the solution increased in percent of potassium oyanide. See curve No. The zinc oonsumed was fairly constant between 0.21 lb. and lb. per ton of solution. See ourve No. The amount of potassium cyanide consumed inoreased more as the solution grew stronger potassium cyanide. slowly In experiment three the atrenght of the solution in potassium oyanide and in gold was kept constant at O.20 and 0.50 oz. respectively. To this solution varying amounts or ammoniaoal sapper hydroxide were added. The preoipitation in each 0&S6 was made with 0.46 lb. of zino dust per ton of solution. Increasing the amount of oopper decreasea the amount of gold precipitated, but there was no regularity in the deorease o the gold reoover1. There was oonsumed from 2.9 lb. to 3.9 lb. of potassium oyanide per ton or solution treated. See ourve No. The zino consumption, as might be expeoted tha solution was made stronger in copper. In order to determine how high increased regularly as See ourve No. peroent the extraotion o gold oould be made with varying amounts

6 4 of gold d O.20 KON solution, solutions.1milar to those in experiment No.1. were made and 3.0 lb. of zino per ton of solu'tion was used in the preoipitation. The axeaab zino was washed onto the ilter and the solution passed thru 80 8S to bring the solution into most intimate oontaot with the zino. It was round that the solutions oould thus be reduoed to oz. per ton of solution.

7 TABLE (NO.1 Amul2t 01 Au COY2staJ2t... ZI2 I{CN Sol 1111 oz. pey o;z Au?f{ecl ojcau Lbs ZI2 -CO%ol Zt2. GOY2-101(CN 1J No. l3efove Af6cv oz / 'toi2 f(egovy l3efoye Afte v surn.plloyl J3efove IF F' - O/ot Y I. 00 O,Z6 O.7Lf O.ZD Z. 0,80 0.'20 0,6.0 7S.O I' 0,2,'27 0,233 'I J Olf o..cr () Z 13 ' O,3{)B 77.0 'I 0.2.& 0 0.;94 If I S I o.is , 0,257 tj. t:o:j., G. 0, /,0 IT O,6J 0./97 'I 7. 0, ,0 O.2CJ 0./97 ' S O.O/S D./97 9. O.OZ 0.0/68 o.oojz /6.0., O.2h7 O. / g:s. /0. 0.0/ O.OOg ,/ (J. Z6Cj 0./ cr / IT /1. o OOS {).o049 o OOiJ/ Z.O,/ /93..

8 Tfif3L[ NO.K /lmout2t ofau Corzs toot.,,. Zn KeN Va Sol. A-v oz pey toj2 liufftfd ;4u Lbs ZYl pey ion ZJ'2 (Of/.- %(cn l Jri. 13 e f< ore A -Iter. 'AfJ.rt tjz/{oi2 /fegoy'y lje ore tey sump/tot{ l3e(oyff 4. J I, O,SO :590 78,t} 0.46 tj.zi& O.?.L! Z I. 00 Z., 0./08 O.J9Z 78.Z./ O.ZJ8 o.zz / D, los 0.39S 79.0 O.Z O.GO /6 0, tj.220 0,40 S 0./08 O,39Z 78'. Z O.Z G. 0./06 0,394 78,8 ().Z68 0/92 0./0 7. O,IOS O,S9S 79,0 I' 0,290 {J, / ,/09 O,J8S 71.0 O,3o:J 0,IS7 tj.os 9.., O,ZOO &0. 0 If O,31S tj./l/s tj, OS /0. II tj,22s 0, Z7S' Jj.O II tj,j4s tj.l1 S (J. 0/ 1I,, ) 0,/ O.JQO (), 070 ooos

9 TABLE NO III. A mouni 't of Av [.on..5(oin..( ZYl J({N Cu Va VI/I'21 00/ Au oz fey ioy2 Z 12.. /6 fy 'ton KeN /(G. I bsfyr; rt. No!3efoye Afler!Jef'ore Afley 0/ {ffovf2 A(lev I ,40 0.4/ o 'Z/0 (J,'z 0,'2.. -e... Z Z. '1 0.3/ It o.z36 '3./4 't 3. / tj. Z4S '1 ::: '1 - tj. ZSS s-. '/ - h {).'Z6S J.se It G,.' O.9Z O.Z7G 0, 3,71 7, 0.9 f3 I, O,Z9ie I, 3,84 B ().JoZ '.,. -0 J.9Lf '.

10 b..... tl ri ----a-. tl - T O / bs c: iv I?,t Jj,s Z!'Z /,(l /bs li{/v,-io-- a _'I'S -,:-6?_Z_{) a-:-r._j 6_._Z_t2 _...,. f\(.c::.. 'b. C) (> c.., c:: '. I' '' -(:) N,. 1 N.... () ;...' / -..,...,..

11 r-'; /(C'.:::oveYr' :,(; tjz/i/./fpterl o - N. <::. I:'''''''''''''''''''''''' + \).,..., i\s.. I.. (J

12 !:,; 'N....= '-= =L..r--...:::!_-:-..:-..,l::::i-:--...,.-''':'' - _ /bs /len f?f' ioa..$o/n..... 'T'.j., j! \ ii

13 ...

14 ...,,.,.

15 .2.8,..C\.. <:::> ;:s c:: ----c c ;..,. <. : C)...