Micronutrient supplement made from copper metal

Abstract

A micronutrient supplement which is made by reacting together copper metal and either hydrochloric acid and/or cupric chloride under oxidizing conditions.

Claims

1. A method of making a micronutrient supplement from copper metal which method consists of the steps of: a) providing as reactants: i) copper metal; ii) one of hydrochloric acid and/or cupric chloride; and iii) an oxidizing agent; and b) conducting a reaction by reacting together reactants i), ii) and iii) according to one of the following chemical equations:
i) 2Cu+HCl+2H.sub.2O.sub.2.fwdarw.Cu.sub.2(OH).sub.3Cl+H.sub.2O,
ii) 3Cu+CuCl.sub.2+1.5O.sub.2+3H.sub.2O.fwdarw.2Cu.sub.2(OH).sub.3Cl,
and
iii) 2Cu+O.sub.2+H.sub.2O+HCl.fwdarw.Cu.sub.2(OH).sub.3Cl, wherein the reaction of step b) produces tribasic copper chloride (Cu.sub.2(OH).sub.3Cl) without any byproducts which would preclude use of the tribasic copper chloride as a pharmaceutically acceptable micronutrient supplement that can be added to animal feed mixtures and fed to animals.

2. A method of making a micronutrient supplement according to claim 1, wherein the copper metal comprises stock copper.

3. A method of making a micronutrient supplement according to claim 1, wherein the copper metal comprises scrap or waste copper.

4. A method of making a micronutrient supplement according to claim 1, wherein in step b) the reactants are reacted in accordance with reaction equation ii) or iii) with the copper metal and one of hydrochloric acid and cupric chloride forming a reaction mixture and the oxygen being injected into the reaction mixture.

5. A method of making a micronutrient supplement according to claim 4, wherein the injection of the oxygen inhibits the copper metal from settling during the reaction.

6. A method of making a micronutrient supplements according to claim 1, wherein the reaction in step b) is conducted at a temperature of about 180 F.

7. A method of making a micronutrient supplements according to claim 1, wherein the reaction in step b) is conducted while stirring the reactants.

8. A method of making a micronutrient supplements according to claim 1, wherein the formed tribasic copper chloride comprises a slurry.

9. A method of making a micronutrient supplements according to claim 8, wherein the slurry is spray dried.

Description

DETAILED DESCRIPTION OF THE DRAWINGS AND THE PRESENTLY PREFERRED EMBODIMENTS

(1) The present invention is directed to micronutrient supplements and methods of preparing the micronutrient supplements. The micronutrient supplements of the present invention can be administered directly to humans or animals as a solid, a suspension or an admixture containing other nutrients such as vitamins, minerals, and food or animal feeds to enhance the survivability, growth, health and/or reproductivity of humans and animals. The basic salt in the micronutrient supplement includes a divalent cation of an essential metal, a pharmaceutically acceptable anion, and a hydroxyl moiety. The micronutrient supplement of the present invention provides good bioavailability of the essential metal in that it is readily absorbed or taken up in a biologically-effective amount. The micronutrient can be combined with other nutrients, particularly vitamins, to provide a premixed supplement. The premixed supplement that includes the basic salt according to the present invention can be stored for extended periods of time without significant decrease in the bioactivity of the included vitamin(s).

(2) An essential metal is defined for the purposes of this invention as a pharmaceutically acceptable metal whose uptake by humans or other animals in a biologically effective amount increases their survivability, growth, health and/or reproductivity. The mode of action of the essential metal is not critical for the present invention. For example, the essential metal can act as a co-factor or a catalyst in a metalloenzyme or metalloprotein; it can be absorbed by a variety of tissues.

(3) Alternatively, the essential metal or a metabolite thereof can inhibit growth of bacteria or other pathogens detrimental to the survivability, growth, health and/or reproductivity of the animal.

(4) According to the present invention the basic metal salt, tribasic copper chloride (Cu.sub.2(OH).sub.3Cl), includes a divalent copper cation, a hydroxyl group and a monovalent chlorine anion. In the microstructure that makes up the basic salt, the copper cation includes a hydroxyl group in its coordination sphere.

(5) The chlorine anion of the basic metal salt is a pharmaceutically acceptable anion. Pharmaceutically acceptable anions are well known in the art. See, for example, S. M. Berge et al. J. Pharmaceutical Sciences, 66:1-19, 1977 for a listing of pharmaceutically acceptable anions, which is incorporated herein by reference.

(6) The chlorine anion that is used in the present invention imparts significant biological effects in its own right. In general specific examples of biologically significant anions include, but are not limited to: iodide, chloride, and phosphate (phosphorus). These biologically significant anions can also be considered as micronutrients, with chlorine anion being particularly useful for purposes of the present invention. Thus, it is within the scope of the present invention to provide basic salts of essential elements that may not necessarily be considered metals such as chloride.

(7) Basic metal salts that are used as micronutrients are generally water insoluble, but their solubility can depend upon pH. Typically, the basic metal salts have some solubility at a low pH, i.e., pH less than about 2.0 to about 0.1. In addition, certain basic metal salts dissolve in water at a high pH, typically at a pH greater than about 7.5 or 8 to about 11.

(8) The basic reaction for producing the micronutrients according to the present invention involves reacting copper metal with hydrochloric acid or cupric chloride (CuCl.sub.2) under oxidizing conditions.

(9) The copper metal can be any type of stock copper or scrap or recyclable copper such as, but not limited to, copper rod mill scale, wire chop, copper filings, copper millings, etc. The copper provided as a powder, in granular form or chopped pieces (e.g. chopped wire), or any form, it being noted that increasing the surface area of the copper such as by reducing the particle size, will increase the reaction rate.

(10) In laboratory bench scale testing, the necessary oxygen was supplied by adding hydrogen peroxide to the reaction mixture. In larger scale testing and commercial applications oxygen can be supplied by injecting oxygen into the reaction mixture. Any suitable conventional oxygen injection system can be used. A particularly suitable oxygen injector system developed during the course of the present invention referred to as a pipeline oxidizer is described below in reference to the working examples.

(11) For the embodiment of the invention in which copper metal is reacted with hydrochloric acid under oxidizing conditions the overall reaction for producing tribasic copper chloride is:
2Cu+O.sub.2+H.sub.2O+HCl.fwdarw.Cu.sub.2(OH).sub.3Cl

(12) The present inventors theorize that the overall general reaction proceeds as follows:

(13) Copper dissolves forming cupric chloride:
Cu+2HCl+O.sub.2.fwdarw.CuCl.sub.2+H.sub.2O(i)

(14) Cupric chloride dissolves more Cu forming cuprous chloride:
CuCl.sub.2+Cu.fwdarw.2CuCl(ii)

(15) Cuprous chloride is oxidized to form tribasic copper chloride and cupric chloride returns to dissolve more copper in step (ii):
12CuCl+3O.sub.2+6H.sub.2O.fwdarw.4CuCl.sub.2+4Cu.sub.2(OH).sub.3Cl(iii)

(16) This reaction can be carried out in a reactor in which the copper metal is added to a mixture of hydrochloric acid and water. Oxygen is added/injected into the reaction mixture and continuously added/injected throughout the reaction.

(17) The reaction mixture is heated to and maintained at a temperature of about 180 F. To prevent metal copper from settling to the bottom of the reaction mixture a mixer of any conventional type that can inhibit material from settling in the bottom of the reactor and/or an oxygen injector that can mix/flush copper metal from the reactor bottom as discussed herein is provided and operated during the reaction.

(18) For the embodiment of the invention in which copper metal is reacted with cupric chloride under oxidizing conditions the overall reaction for producing tribasic copper chloride is:
3Cu+CuCl.sub.2+1.5O.sub.2+3H.sub.2O.fwdarw.2Cu.sub.2(OH).sub.3Cl

(19) The reaction can be carried out in a reactor in which the copper metal is added to a mixture of the cupric chloride and water. As in the reaction above, oxygen is added/injected into the reaction mixture and continuously added/injected throughout the reaction.

(20) The reaction mixture is heated to and maintained at a temperature of about 180 F. and a mixer of any conventional type that can inhibit material from settling in the bottom of the reactor and/or an oxygen injector that can mix/flush copper metal that might otherwise settle in the bottom of the reactor as discussed herein is provided and operated during the reaction.

(21) Either of the reactions can be conducted in a batch mode, semi-batch mode or in a continuous manner.

(22) Each reaction produces a solid slurry of tribasic copper chloride crystals which can be spray dried or processed in any manner to recover the tribasic copper chloride crystals. According to one embodiment a digestible binder can be added to the solids slurry and the resulting slurry can be agglomerated by spray drying or other means of agglomeration to form agglomerates of the micronutrient crystals as taught in U.S. Patent Application Publication No. 2013/0064963.

(23) The micronutrient supplements of the present invention can be admixed with other nutrients. Nutrients include both micro- and macronutrients. Examples of micronutrients include vitamins and minerals. Examples of vitamins useful for the present invention include: vitamin A, vitamin D.sub.3, vitamin E (tocopherol), vitamin K (menadione), vitamin B.sub.12 (cyanocobalamin), vitamin B.sub.6, vitamin B.sub.1, vitamin C (ascorbic acid), niacin, riboflavin, thiamine mononitrate, folic acid, calcium pentothenate, pyridoxine, choline chloride, biotin, known pharmaceutically acceptable derivatives of these vitamins and mixtures thereof. Examples of minerals or metal salts useful for the present invention include copper sulfate, iron sulfate, zinc oxide, manganese, iron, iodine, selenium, amino acid complexes of the trace metals and mixtures thereof. The macronutrients that can be used in the present invention include any of the common feed ingredients such as, for example, grain, seeds, grasses, meat meal, fish meal, fats and oils.

(24) Features and characteristics of the present invention will be exemplified by the following examples which are provided as a non-limiting example for illustrative purposes only.

(25) The following Examples include laboratory bench trials and pilot scale trials.

(26) The laboratory bench trials were conducted in glass beakers on heated, magnetic stir plates or in some cases top mounted mixers were employed. In all cases the chemistry and recipes were similar in that copper was added to a mixture of HCl and water, at or near stoichiometric ratios to produce basic copper chloride. The mixtures were mixed and heated to about 180 F. For all the laboratory trials 30% hydrogen peroxide was used as the oxygen source. The hydrogen peroxide was added incrementally throughout the trials as needed to convert Cu.sup.+ to Cu.sup.++. The target recipe for the mixtures were designed to yield 50% by weight solids slurries of tribasic copper chloride crystals which was determined to be suitable for spray drying.

(27) The pilot scale trials were conducted in cone bottom, fiberglass mix tanks equipped with live steam injection for temperature control. The recipes used in the pilot trials were similar to those used in the laboratory bench trials however gaseous oxygen was utilized as the oxygen source rather than hydrogen peroxide. The O.sub.2 gas is more efficient both from a cost and processing standpoint. The oxidation was accomplished through a pipeline oxidizer. This set up consisted of a pump which draws from the top of the tank (to avoid inclusion of large copper pieces) and pumps through 100 coil and then back into the bottom of the tank. Oxygen is injected inline just before the coil. Static mixers were provided at the beginning and end of the coil to provide intimate mixing of the oxygen with the liquid stream. The concept is to provide good contact and residence time under pressure to yield high oxidation efficiencies. The discharge of the pipeline oxidizer entering the bottom of the cone provided two functions: 1) Mixing/flushing action to any copper pieces that may have settled to the bottom of the cone to prevent plugging; and 2) Providing a Cu.sup.++ rich solution to any settled copper in the bottom of the reactor to continue to drive the reaction. Also any unreacted oxygen gas has a second chance to oxidize Cu.sup.+ inside the mix tank increasing oxidation efficiency.

Example 1

(28) In this Example basic copper chloride was produced by reacting fine copper metal powder with hydrochloric acid and hydrogen peroxide according to the following reaction.
2Cu+HCl+2H.sub.2O.sub.2Cu.sub.2(OH).sub.3Cl+H.sub.2O

(29) The reactants are added at or near their stoichiometry amounts. HCl was added at a slight excess to assist in driving the reaction. 61 ml of water was first added to a 250 ml beaker followed by 46 ml of 32% HCl. While mixing, 53.57 g/1 of copper powder was added to the beaker. The temperature of the beaker was maintained at or near 180 F. Throughout the trial 30% hydrogen peroxide was added incrementally to convert Cu.sup.+ as it formed to Cu.sup.++. The reaction was allowed to proceed for a total of 24 hours. During the reaction time the mixture transitioned from clear to dark brown (cuprous chloride) solution to dark brown solution with white crystals of cuprous chloride, and then finally to a thick slurry of bright green crystals (tribasic copper chloride). At the end of the 24 hour period there was no visible copper present. A sample of the slurry was dried and analyzed by XRAY Diffraction to determine crystal structure. The results showed that the material was 99.1% basic copper chloride (defined as atacamite and clinoatacamite) and 0.1% cuprous chloride. The solids content of the slurry was about 50% solids, which was determined to be suitable for purposes of spray drying.

Example 2

(30) The process and recipe for this Example were exactly the same as in Example 1 however the copper source was a bare bright, copper wire chop. The copper was of a size and density that would not allow it to be evenly dispersed through the solution as was the copper powder in Example 1. The copper remained in the bottom of the beaker and was being moved around by the mixing action. During the trial the same transitions were observed throughout the trial as were in Example 1 however at a much slower rate. After 24 hours it was visually estimated that about 50% of the copper had been converted to basic copper chloride. After about 32 hours of reaction time the contents of the beaker had turned to the typical green color of basic copper chloride however there was still unreacted copper metal still visible on the bottom of the beaker. Analysis showed a 70% conversion of the copper into basic copper chloride.

Example 3

(31) In this Example basic copper chloride was produced from copper rod mill scalea byproduct from copper rod manufacturing. The copper rod mill scale was granular and included about 50 wt. % copper with a balance of cuprous oxide and cupric oxide. The copper assay on the material used was about 87.46 wt. % copper.

(32) In this Example 70 ml of water was first added to a 250 ml beaker followed by 45.1 ml of 32% HCl. While mixing, 68.05 g/1 of copper rod mill scale was added to the beaker. The temperature of the beaker was maintained at or near 180 F. Throughout the trial 30% hydrogen peroxide was added incrementally to convert Cu.sup.+ as it formed to Cu.sup.++. The reaction was allowed to proceed for a total of 24 hours. During the reaction time the mixture transitioned from clear to dark brown (cuprous chloride) solution to dark brown solution with white crystals of cuprous chloride, and then finally a thick slurry of bright green crystals (basic copper chloride). At the end of the 24 hour period there was no visible copper present. A sample of the slurry was dried and analyzed by XRAY Diffraction to determine crystal structure. The results showed that the material was 95.7% basic copper chloride (defined as atacamite and clinoatacamite) and 4.3% cuprous oxide.

Example 4

(33) In this Example a pilot scale trial was performed to convert copper chop to basic copper chloride using cupric chloride in place of HCl. The basic copper chloride was produced by reacting cupric chloride with copper metal by the following reaction:
3Cu+CuCl.sub.2+1.5O.sub.2+3H.sub.2O=2Cu.sub.2(OH).sub.3Cl

(34) This pilot trial was performed in a 5000 gallon, cone bottom fiberglass mix tank equipped with a pipeline oxidizer as described above. The recipe was designed to yield about 11,000 lbs of basic copper chloride assuming a 100% completion of reaction.

(35) The cupric chloride used in this trial contained 188 g/l of Cu and 1.34N free hydrochloric acid. 844 gallon of this solution was transferred to the mix tank along with 715 gallon of water. While mixing, 5229 lbs of copper wire chop was added incrementally over 12 hours at a rate of 110 lb/15 min. After the first addition of copper, the pump was started to send flow through the pipeline oxidizer. Oxygen injection into the pipeline was also started at this time. Progress was monitored by measuring total copper and density of the mixture. The reaction rate slowed dramatically after 24 hours and after 48 hours seemed to have almost completely stalled. After 48 hours of reaction a total of 77.4% of the copper had been converted to basic copper chloride.

(36) The basic metal salts of this invention can be used to enhance the survivability, growth rate, health and/or reproductivity in humans and other animals. While not to be bound by any theory, it is thought that the basic metal salts are more readily absorbed and/or exhibit an increased bioavailability over minerals, inorganic metal salts or other nutrients containing the corresponding essential metals. It has been determined the preferred embodiments of the basic metal salts of this invention significantly reduce the growth of bacteria, thus indicating the use of preferred forms of this invention can effectively enhance the growth and health of humans and other animals. Furthermore, the preferred basic metal salts of this invention demonstrate an enhanced efficacy against certain bacteria, thereby allowing for the use of smaller amounts and/or lower concentrations of the essential metals to provide substantially equal or equal potent effects on animals.

(37) Although the present invention has been described with reference to particular means, materials and embodiments, from the foregoing description, one skilled in the art can easily ascertain the essential characteristics of the present invention and various changes and modifications can be made to adapt the various uses and characteristics without departing from the spirit and scope of the present invention as described above and set forth in the attached claims.