Nov 26 2014 The paper concerns a hydrometallurgical method for selective recovery of copper from lowgrade electric and electronic wastes The following consecutive stages were proposed smelting of the scraps to produce CuZnAg alloy leaching of the alloy in ammoniacal solution and selective copper electrowinning CuZnAg alloy was a polymetallic and fivephase system
Ammonium sulfate byproduct is marketed as fertilizer other workers12 precipitated copper by adding ammonium bisulfite to cuso4 solution in another process13 14 it was suggested to add sodium bisulfite or magnesium bisulfite instead of ammonium sulfite to the copper sulfate leach solution and heat to 80 c to precipitate chevreuls salt
Ammonium carbonate being 03 m for the system with a leaching time of 120 minutes giving them over 98 of copper recovery highest recovery for ammonia alone was 53 with only 5 of copper being recovered when using ammonium carbonate the increase in recovery of copper from the malachite was also due to the
Thiosulfate leaching of natural acanthite ore in copperammoniaammonium sulfate medium by yueh yves lai bsc university of alberta 2014 a thesis submitted in partial fulfillment of the requirements for the degree of master of applied science in the faculty of
Thus precipitation of copper does not occur during leaching because ammonium sulfate solutions have mildly acidic character ferric ions fe 3 passing into the solution during the leaching process precipitate in the form of feoh 3thus a high purity solution can be obtained
Copper etching reactions the circuit board etching step takes the solid copper metal from the pcb into solution as copper ions cu2 the chemical reaction causing the metal to dissolve is a corrosion reaction involving the persulfate ion and the copper atoms on the board the sodium
Copper and copper alloys suffers rapid attack by concentrated solution of ammonium hydroxide to form a soluble complex of copperammonium compound in some cases the corrosion of copper exposed to dilute solution of ammonium hydroxide is low copper specimen submerged at room temperature for one week in 001n ammonium hydroxide solution
Ammonia leaching abstractof the disclosure an improved process for obtaining copper from a copper sulfide in which the copper sulfide is treated with oxygen and an aqueous leaching solution of ammonium carbonate to form a leach liquor which contains ammonia complexes of copper sulfate and copper carbonate the leach liquor is heated to form gaseous ammonia and carbon dioxide the leach
Processes for recovering gold from coppergold ores thiosulfate leaching or gold ores copper catalyzed thiosulfate leaching using ion exchange technology are disclosed the processes include subjecting the goldbearing and copperbearing thiosulfate solution to a ph andor temperature adjustment to reduce tetrathionate concentration in the thiosulfate solution prior to contacting with an ion
Ammonia leaching phelps dodge corporation 21081979 preferably the leaching step is carried out with an ammonium carbonate solution containing a molar excess of ammonium carbonate relative to copper eg 2050 preferably about 30 molar excess of ammonium carbonate and containing free ammonia eg 1050 grams of ammonia per liter of leaching solution preferably about 25 grams
The leaching speed of copper in an ammonia solution containing ammonium chloride was higher than that in an ammonia solution containing ammonium sulfate key words copper dissolution ammonia solution waste leaching hydrometallurgical process 1 introduction the metals recovery from waste materials is important for
Aug 03 2010 abstract the leaching of copper from the tailings of baifang copper mine in hunan province in china by aqueous ammoniaammonium chloride solutions has been studied the tailings belong to a lowgrade and highalkaline copper ore the effect of leaching time the concentration of ammonia solidliquid ratio and temperature were investigated
Jul 18 2013 the general feasibility of ammoniacal percolation leaching of copper sulphide ores has been demonstrated the rates are comparable to those of conventional ferric sulphatesulphuric acid systems but without the attendant problems of carbonate or iron dissolution for the ore column heights studied the copper leaching rate increased approximately as the square root of the total nh 3
The best leaching efficiency for copper in their feasibility of copper leaching from an industrial sludge using ammonia solution this present work will develop the effect of nitric acidammonia ratio on the leaching of rich cobalt copper oxidised ore it will also evaluate the effect of key parameters time ammonia concentration and ph
Corpus id 39194869 ammonia nitric acid leaching of coppercobalt oxidized ore inproceedingstshilomboammonian titleammonia nitric acid leaching of coppercobalt oxidized ore authork g tshilombo and a mulababafubiandi
Kinetics of leaching of copper metal in copperiiammonium sulphate solutions as determined by the rotating disc method hydrometallurgy 1978 3 3 233248
Ammonia leaching without oxidants therefore it makes a focus that how to extract bornite in ammoniacal solution persulfate is known to be a strong oxidant in the basic solutions and has been used as a leaching agent for the recovery of metal in alkaline solutions 2021 the dissolution of lowgrade copper ore in ammonia
Various leaching and bioleaching processes for the sarcheshmeh copper concentrate have been studied 13 the main disadvantages of these processes are their slow kinetics and low copper recovery use of ammonia as an attractive alternative is favorable due to its high complexation
The gallcopper process was recorded as being used during the song dynasty 9601271ad copper was precipitated from solution by dipping iron into the blue vitriol solution a process identified as early as 150 bc in china 6 therefore presumably the recognition of a natural copper leaching process can be identified as early as that date
Mar 01 2014 the present work describes an investigation of a chemical process for the recovery of copper and iron from malachite ore for the dissolution of copper and iron h 2 so 4 was employed as well as h 2 o 2 as an oxidizing agent the effects of reaction temperature and time acid concentration liquidtosolid ratio and agitation rate on the copper and iron percentage were investigated
Jun 24 2004 in this study the leaching kinetics of malachite cuco3 cuoh2 an oxidized copper ore was investigated in water saturated with ammonia gas in the experiments the ammonia concentration of the solution the particle size of the ore the temperature the stirring speed and the solidtoliquid ratio were chosen as parameters it was determined that the leaching rate of malachite
Feb 22 2011 ammonium is added on a regular basis to produce uniform and lustrous deposits and to improve anode corrosion excess ammonium can cause copper i to form which hinders adhesion but ammonium is easily lost by evaporation oxalate is a buffer operation copper pyrophosphate baths are difficult to control
Optimum leaching conditions were found as follows aps concentration is 200 g l 1 ammonium carbonate concentration is 200 g l 1 leaching time is 180 min leaching temperature is 60 c solidliquid ratio is 0 04 g ml 1 and stirring speed is 400 rev min 1 under these conditions copper extraction yield was obtained at about 72
The experiments of agitation leaching were carried out in aqueous ammoniaammonium carbonate solution to recover copper from the flotation tailings of waste copper oxide residue the main copper minerals contained in the flotation tailings are chrysocolla malachite and cuprite with the copper
In this process ammonia leaching of sulfide minerals of copper nickel cobalt and iron was conducted at a temperature of about 105 c and air pressure of 8 atm under these conditions copper
Susumu morioka kazuyoshi shimakage studies on the ammonia pressure leaching of metallic nickel and copper powders transactions of the japan institute of metals 102320matertrans196012197 12 3 197205 1971
Copper ions passing into the solution form copper amine complexes with ammonia the formation reactions of the copper amine complexes can be written as follows 2 2 cu 2 nh cu nh332 2 22 cu nh 2 nh cu nh33 324 3 thus precipitation of copper does not occur during leaching
Jan 01 2005 copper recoveries for 5 30 120 and 140 min of leaching by nh 4 ohnh 4 2 co 3 solution are given in fig 3these results indicate that the copper recoveries increase with increasing leaching times for each ammoniaammonium concentrations that is for 5 m nh 4 oh03 m nh 4 2 co 3 leaching conditions the copper recovery is 49 at the end of 5 min of leaching and it
Nov 14 2013 recovery of zn cu and fe from the copper smelter slag was studied slag was treated with nh 4 cl at 320 c and product was subjected to water leaching metal recoveries to the solution were 915 zn 897 cu and 883 fe
Copper corrosion in home plumbing systems is a common phenomenon which can have many causes besides actual piping failure the telltale blue stains the oxidized copper leaves on sinks tubs and fixtures can identify copper corrosion often laundry and even blonde hair can be tinted blue copper can be toxic and watercontaining levels over
Aug 03 2014 the leaching behavior of a copper flotation concentrate was investigated using ammonium persulfate aps in an autoclave system the decomposition products of aps active oxygen and acidic medium were used to extract metals from the concentrate leaching experiments were performed to compare the availability of aps as an oxidizing agent for leaching of the
