Low energy method of preparing basic copper carbonates

Abstract

A method of forming basic copper carbonates includes providing an aqueous solution comprising copper (II) ammonia, and carbonic acid; and adding sufficient carbon dioxide to precipitate a basic copper carbonate from the aqueous solution.

1 .- 10 . (canceled) 
   
   
       11 . A method of forming basic copper carbonate comprising: contacting copper (II) hydroxide with an aqueous solution comprising an amine and a sufficient amount of carbonic acid to convert at least one fourth of the copper hydroxide to basic copper carbonate; under conditions where the copper hydroxide is converted to basic copper carbonate; and recovering the basic copper carbonate. 
   
   
       12 . The method of  claim 11 , wherein the amine is ammonium hydroxide. 
   
   
       13 . The method of  claim 12 , wherein the copper hydroxide is formed by contacting copper metal with an oxidant and an aqueous solution comprising ammonium hydroxide under conditions that the copper metal is converted to copper hydroxide. 
   
   
       14 . (canceled) 
   
   
       15 . The method of  claim 11 , wherein the basic copper carbonate is one selected from the group consisting of azurite, malachite, and mixtures thereof. 
   
   
       16 . A method of preparing basic copper carbonate comprising:
 (a) providing a solution of copper (II), the solution comprising copper (II), an amine, carbonic acid, and water in a reaction vessel,   (b) adjusting the pH of the solution until basic copper carbonate is formed; and   (c) recovering the basic copper carbonate.   
   
   
       17 . The method of  claim 16 , wherein the temperature of the solution ranges from about 20° C. to about 100° C. 
   
   
       18 . The method of  claim 16 , wherein the temperature of the solution is from about about 25° C. to about 80° C. 
   
   
       19 . The method of  claim 16 , wherein reaction vessel is a spray chamber, a stirred tank reactor, a rotating tube reactor, or a pipeline reactor. 
   
   
       20 . The method of  claim 16 , wherein the pH is adjusted by increasing or decreasing the CO 2  concentration. 
   
   
       21 . The method according to  claim 16 , wherein step (b) is carried out at ambient pressure. 
   
   
       22 . The method of  claim 16 , wherein the pressure in the reaction vessel during step (b) ranges from about 0 psig to about 1500 psig. 
   
   
       23 . The method of  claim 22 , wherein the pressure in the reaction vessel during step (b) ranges from about 20 psig to about 500 psig. 
   
   
       24 . The method of  claim 23 , wherein the pressure in the reaction vessel during step (b) ranges from about 80 psig to about 250 psig. 
   
   
       25 . The method of  claim 16 , wherein step (b) is carried out in a batch reaction vessel. 
   
   
       26 . The method of  claim 16 , wherein the method is carried out as a continuous process. 
   
   
       27 . The method of  claim 16 , further comprising introducing a copper metal-containing material into the solution of step (a), the latter being introduced into the reaction vessel. 
   
   
       28 . The method of  claim 16 , further comprising introducing a copper metal-containing material into the solution which remains after the removal of BCC in step (c) to provide a replenished copper solution. 
   
   
       29 . The method of  claim 28 , further comprising oxidizing the copper metal-containing material, and introducing the oxidized copper metal into the solution which remains after the removal of BCC in step (c) to provide a replenished copper solution. 
   
   
       30 . The method according to  claim 28 , wherein the replenished copper solution is introduced into the reaction vessel. 
   
   
       31 . The method according to  claim 29 , wherein the replenished copper solution is introduced into the reaction vessel. 
   
   
       32 . The method of  claim 27 , wherein the copper metal-containing material is bronze, copper alloys, copper clads, or copper compounds. 
   
   
       34 . The method according to  claim 16 , wherein during step (b) the molar ratio of ammonia to copper (II) in the reaction vessel ranges from about 2.7 to about 3.8; the temperature of the solution in the reaction vessel ranges from about 48° C. to about 80° C.; and the pressure in the reaction vessel ranges from about 20 psig to about 500 psig. 
   
   
       35 . The method according to  claim 36 , wherein during step (b) the molar ratio of ammonia to copper (II) in the reaction vessel ranges from about 2.7 to about 3.2; the temperature of the solution in the reaction vessel ranges from about 60° C. to about 75° C.; and the pressure in the reaction vessel ranges from about 80 psig to about 250 psig. 
   
   
       36 . The method of  claim 28 , wherein the copper metal-containing material is bronze, copper alloys, copper clads, or copper compounds. 
   
   
       37 . The method of  claim 28 , wherein the method is carried out as a continuous process. 
   
   
       38 . The method of  claim 31 , wherein the method is carried out as a continuous process. 
   
   
       39 . The method of  claim 34 , wherein the method is carried out as a continuous process. 
   
   
       40 . A method of forming azurite comprising: contacting copper metal with an aqueous solution comprising: an amine; carbonic acid; and oxygen, under conditions where the copper metal is converted into azurite; and recovering the azurite. 
   
   
       41 . The method of  claim 40 , wherein the amine is ammonia. 
   
   
       42 . The method of  claim 41 , wherein the amount of copper metal is such that there is at least one mole of copper for every two moles of ammonia. 
   
   
       43 . The method of  claim 42 , wherein the amount of copper metal is such that there is at least 1.2 moles of copper metal for every mole of ammonia. 
   
   
       44 . The method of  claim 41 , wherein the ammonia is present in the aqueous solution in an amount of about 15 g/L calculated as NH 3 . 
   
   
       45 . The method of  claim 40 , wherein the pH of the composition is between 8 and 10. 
   
   
       46 . The method of  claim 40 , wherein the temperature of the composition is between 25° C. and its boiling temperature. 
   
   
       47 . The method of  claim 40 , wherein the process is a batch or a continuous process, and wherein the aqueous solution at the beginning of the reaction further comprises between 0.1 to 15 grams of soluble copper ions per liter of soluble copper. 
   
   
       48 . A method of forming basic copper carbonate having the formula: (CuCO 3 ) x (Cu(OH) 2 ) y , wherein y is 1 and x is greater than 1 comprising: contacting copper metal with an aqueous solution comprising: an amine; carbonic acid; and oxygen, under conditions where the copper metal is converted into basic copper carbonate having the formula: (CuCO 3 ) x (Cu(OH) 2 ) y , wherein y is 1 and x is greater than 1; and recovering the basic copper carbonate having the formula: (CuCO 3 ) x (Cu(OH) 2 ) y , wherein y is 1 and x is greater than 1. 
   
   
       49 . The method of  claim 48 , wherein the amine is ammonia. 
   
   
       50 . The method of  claim 49 , wherein the amount of copper metal is such that there is at least one mole of copper for every two moles of ammonia. 
   
   
       51 . The method of  claim 50 , wherein the amount of copper metal is such that there is at least 1.2 moles of copper metal for every mole of ammonia. 
   
   
       52 . The method of  claim 49 , wherein the ammonia is present in the aqueous solution in an amount of about 15 g/L calculated as NH 3 . 
   
   
       53 . The method of  claim 48 , wherein the pH of the composition is between 8 and 10. 
   
   
       54 . The method of  claim 48 , wherein the temperature of the composition is between 25° C. and its boiling temperature. 
   
   
       55 . The method of  claim 48 , wherein the process is a batch or a continuous process, and wherein the aqueous solution at the beginning of the reaction further comprises between 0.1 to 15 grams of soluble copper ions per liter of soluble copper.