USOO741 1 080B2 (12) United States Patent (10) Patent No.: US 7.411,080 B2 Zhao (45) Date of Patent: Aug. 12, 2008 (54) DIRECTSYNTHESIS OF COPPER 3,635,668 A 1/1972 Barker ......................... 23,147 CARBONATE 4490,337 A 12/1984 Richardson ....... ... 423/43 4,944.935 A 7, 1990 Langner et al. ... ... 423f604 (75) Inventor: Gang Zhao, Sumter, SC (US) 6,596,246 B2 * 7/2003 Huato et al. .................. 423/42 2004/0191143 A1* 9, 2004 Richardson et al. ........... 423/32 (73) Assignee: retro-Ich. Inc., Ridgefield Park, NJ * cited by examiner Primary Examiner P. Nazario Gonzalez (*) Notice: Subject to any disclaimer, the term of this (74) Attorney, Agent, or Firm—Christopher G. Hayden; patent is extended or adjusted under 35 Hayden Stone PLLC. U.S.C. 154(b) by 267 days. (57) ABSTRACT (21) Appl. No.: 11/436,528 A basic copper salt selected from basic copper carbonate, (22) Filed: May 19, 2006 basic copper Sulfate, basic copper acetate, basic copper cit rate, and basic copper nitrate is manufactured by contacting (65) Prior Publication Data copper metal with an aqueous Solution having ammonia; an US 2007/O269362 A1 Nov. 22, 2007 acid selected from carbonic acid, Sulfuric acid, acetic acid, • 1-1-9 nitric acid, or citric acid; and oxygen, under conditions where (51) Int. Cl. the copper metal is converted to the basic copper salt; and then C07F I/08 (2006.01) recovering the basic copper salt. The most economical COIB 2/06 (2006.01) embodiment is where the ammonia is present in the aqueous COIB 3L/30 (2006.01) solution is in an amount between about 6.7 g/l and about 15 g/1 (52) U.S. Cl. S56/114 calculated as NH, and the pH of the composition is between 58) Field of c - - - - - ificati- - - - - -s - - - - - - - h- - - - - - - - - - - - - - - - - - - - 556/114 8 and 10, and the temperature of the composition is between (58) Field of Classification "s/352.46.426 2 517 25° C. and 100° C. The method is particularly useful if the S lication file f let s h hi t • 1s basic copper salt is basic copper carbonate. The basic copper ee appl1cauon Ille Ior complete searcn n1Story. carbonate produced has the formula: (CuCO), (Cu(OH), (56) References Cited where y is 1 and X is between 0.1 to less than 1; or where y is 1 and X is 1, or where y is 1 and X is between 0.5 to less than U.S. PATENT DOCUMENTS about 0.95, or where y is 1 and X greater than 1. 2,536,096 A 1/1951 Rowe .......................... 23,147 2,536,097 A * 1/1951 Percy ......................... 423,517 24 Claims, No Drawings US 7,411,080 B2 1. 2 DIRECT SYNTHESIS OF COPPER ions from the first salt and the anions from the second salt CARBONATE form a precipitate. This is extremely inefficient. First, the copper metal must be converted into a soluble salt, which is CROSS-REFERENCE TO RELATED typically copper chloride, copper nitrate, or copper Sulfate. APPLICATIONS Second, the mixture of the two salts in water results in a large amount of waste brine (with residual copper) which must be None treated prior to disposal. Third, the resulting copper salt invariably has a large amount of contamination from the STATEMENT REGARDING FEDERALLY anions and/or cations present in the two salts. SPONSORED RESEARCH ORDEVELOPMENT 10 Basic copper carbonate (Cu(OH)2CO) (hereafter “BCC) is used in a variety of applications, for example in NFA. pigments, pyrotechnics, insecticides, fungicides, astringents, and even as a feed additive. The traditional route to producing INCORPORATION-BY-REFERENCE OF BCC is by adding Sodium carbonate to a solution of copper MATERIAL SUBMITTED ON A COMPACT DISC 15 Sulfate, followed by filtering, washing, and drying. There are two inefficiencies in this method. First, copper sulfate must be NFA. prepared from copper metal or from other sources, and sec ond, the washing of the solution in an attempt to remove the SEQUENCE LISTING residual Sulfates is expensive and produces a considerable amount of waste water requiring treatment before disposal. NFA. The formula for basic copper carbonate can be represented as CuCO Cu(OH), and while the theoretical amount of cop FIELD OF THE INVENTION per in basic copper carbonate is 57.48%, under manufactur ing methods used today 56.0% is as high as conventionally The present invention relates to the direct formation of 25 practical. Generally, basic copper carbonate manufactured by basic copper salts such as basic copper carbonate, basic cop this method has a high sodium content and a high Sulfate per Sulfate, basic copper acetate, and basic copper nitrate. content that can not be readily reduced by simple washing. There are a number of other basic copper salts that are BACKGROUND OF THE INVENTION useful. Basic copper acetate is used as a pigment, insecticide, 30 fungicide, mildew preventative, and as a mordant in dyeing. Scrap and recycled copper metal is a plentiful and inexpen The chemical formula for basic copper acetate include blue sive form of copper. While some of this metal is simply verdigris, Cu(CHCOO).Cu(OH) and green verdigris, 2Cu smelted to form copper stock, another valuable use of this (CHCOO), Cu(OH). Note that informulas provided herein copper is the production of copper salts. Copper salts, of waters of hydration are typically not included. Basic copper varying purity, are used as a Supplement in animal feed, are 35 sulfate (CuSO-3Cu(OH)) is also extensively used in indus used in fungicides, are used as pigments, and are used in a try, as a fungicide, and as a micronutrient for plants. Basic variety of other chemical processes. copper nitrate is also useful. Commercial preparation of these It is known to produce copper hydroxide in a two-stage materials in each case requires the reaction of two dissolved process from a previously produced copper salt, such as cop salts to form the relatively insoluble product, and as a result per Sulfate, copper carbonate or copper oxychloride, in a 40 there are costs associated with manufacturing the reactant process in which alkali are added to effect a precipitation of salts and in removing contaminants. copper hydroxide at a temperature below 20°C., as described What is needed is a method of directly forming a variety of in for example U.S. Pat. Nos. 3,635,668 and 4,490,337. There basic copper salts from copper metal. are also known methods of forming copper hydroxide directly from scrap metal. U.S. Pat. No. 2.536,096 discloses a single 45 SUMMARY OF THE INVENTION stage process in which copper hydroxide is produced directly from Scrap copper in a solution of ammonia in concentrations In a broad aspect the invention encompasses a novel in excess of 10 g/l of soluble ammonium and preferably in method of synthesizing selected basic copper salts including excess of 30 g/l. U.S. Pat. No. 4,944.935 describes a process basic copper carbonate, basic copper Sulfate, and basic cop wherein copper metal is treated at a temperature of 0° to 40° 50 per acetate directly from copper metal using water, an amine with an aqueous solution which contains 0.1 to 10 g/l ammo (preferably ammonia), an oxidizing source (preferably oxy nium salt or ammonium hydroxide (calculated as NH) with gen), and a source of anions. Advantageously the reaction stirring and with a simultaneous introduction of an oxygen takes place in a single reactor. Advantageously the oxidant is containing gas, and the particulate copper(II) hydroxide reac a gas comprising oxygen, Such as Oxygen, an oxygen/inert gas tion product is separated from the copper metal. This patent 55 mixture Such as oxygen and nitrogen, air, or any combination Suggests using in the dissolution material 0 to 5 g/l copper(II) thereof. The reaction process can be a batch process or a salt to make the reaction uniform. continuous process. For a batch process, the reaction is con Basic copper chloride (copper oxychloride) can beformed tinued until the desired conversion of copper to basic copper by treating copper carbonate with hydrochloric acid. The salt is achieved. For continuous processes, advantageously production of basic copper chloride via a reaction of copper 60 the liquid in the reaction vessel is circulated with sufficient metal and a chlorine source is known. Basic copper chloride Velocity to carry the basic copper salt particles as a slurry, and may be manufactured either by the action of hydrochloric this slurry is cycled to a separation unit (Such as a filter, a acid on copper metal or by the air oxidation of cuprous chlo centrifugal separator, or a settling tank) where the particles of ride Suspensions. basic copper salt are recovered. For the manufacture of basic However, to make other basic copper salts, heretofore the 65 copper Sulfate, the preferred sources of sulfate are ammonium method of production has been to mix a first soluble copper sulfate and/or sulfuric acid. Acid is more preferred over the salt with a second salt, under conditions where the copper ammonium salts. The anion source should contain Sufficient US 7,411,080 B2 3 4 acidity (Sulfuric acid as opposed to ammonium sulfate) to preparation (from metal or other sources), the cost of sodaash control the pH to the desired set point, where the degree of as well as the washing step to remove the sodium Sulfate incorporation of the anion into the basic copper salt depends by-product. on this pH set point. Using only ammonium sulfate would The invention includes a method of forming basic copper provide an undesirable excess of ammonia in the composi salt selected from basic copper carbonate, basic copper Sul tion, and the pH would be such that very little if any of the fate, basic copper acetate, and basic copper nitrate, the anion would be incorporated into the salt.