Hydrometallurgical leaching of nickeliferous ores

Abstract

Process for extracting nickel from a feed ore comprising a mineralized form of iron and a mineralized form of nickel.

Description

BANIQL 3013654.004HYDROMETALLURGICAL LEACHING OF NICKELIFEROUS ORES CROSS REFERENCE TO RELATED APPLICATIONS

[0001] The present application claims benefit of U. S. Provisional Patent Application Serial No. 63 / 719,878, filed on November 13, 2024 and U. S. Provisional Patent Application Serial No. 63 / 779,825, filed on March 28, 2025. The entire contents of the aforementioned applications are hereby incorporated by reference.FIELD OF THE DISCLOSURE

[0002] The present disclosure generally relates to a process for acid leaching of ores rich in iron, e.g., laterite ores, to recover nickel and / or cobalt.BACKGROUND OF THE DISCLOSURE

[0003] Annual increases in stainless steel production and the rapid development of batteries, new materials, and other industries have boosted market demand for nickel and cobalt resources. In general, nickel ores are classified as oxides or sulfides. Oxides include laterite, where the principal mineral mixtures are nickeliferous limonite, and garnierite (a mixture of various hydrous nickel and nickel-rich silicates). Nickel sulfides commonly exist as solid solutions with iron in minerals such as pentlandite and pyrrhotite. With the continued depletion and dilution of nickel sulfide ore, the main development direction for the exploitation and utilization of nickel resources has gradually focused on laterite nickel ores.

[0004] Laterite ores, mainly found in Australia, the Philippines and Indonesia, typically comprise three fractions: the limonite fraction beneath surface soil, the saprolite fraction above the bed rock, and ores in the transitional zone between limonite and saprolite. The nickel-containing mineral in limonite is typically goethite and / or hematite. The nickel-containing minerals in saprolite are mostly coarse siliceous phases such as serpentine, garnierite, chlorite, nontronite, and smectite. The ore in the transition zone typically contains both limonite and saprolite. Although nickel ore with different properties is distributed in layers, there is no obvious boundary between the layers. With the undulation of terrain, it is difficult to separate the nickel ore having a specific property from others during mining, resulting in the mixing of nickel ore having different properties, which also brings a challenge to stability of the treatment process.BANIQL 3013654.004

[0005] Numerous routes to process nickel laterite ores have been proposed, including hydrometallurgical routes such as high-pressure acid leaching, atmospheric pressure acid leaching and heap leaching, each of which offers its respective advantages and disadvantages that are dependent, at least in part, upon ore mineralogy. For example, in US Patent Publication No. 2023 / 0227326A1, Li et al. proposed an integrated process for extracting nickel from a mixture of ores having different mineralogy the following steps: (1) sorting the laterite nickel ore to obtain lump ore and sediment ore; (2) crushing the lump ore, and then performing heap leaching, to obtain a crude nickel sulfate solution A; (3) separating the sediment ore to obtain high chromium ore, low iron, high magnesium ore, and high iron, low magnesium ore, and drying, roasting, reducing, and sulfurating the low iron, high magnesium ore to obtain low nickel matte; (4) blowing and performing water extraction on the low nickel matte, and then performing oxygen pressure leaching, to obtain a crude nickel sulfate solution B; (5) performing pressure leaching on the high iron, low magnesium ore to obtain a crude nickel sulfate solution C; and (6) performing extraction on the crude nickel sulfate solution A, the crude nickel sulfate solution B, and the crude nickel sulfate solution C, and then evaporating and crystallizing, to obtain battery-grade nickel sulfate. Li et al., US Patent Publication No. 2023 / 0227326A1 at

[0017] -

[0024] ,

[0006] Although the approaches proposed to date for extraction of nickel from laterite and other nickeliferous ores enable the extraction of nickel from a range of ores, significant room for improvement remains.SUMMARY OF THE DISCLOSURE

[0007] Among the various objectives of the present disclosure is a process for producing battery-grade nickel from nickeliferous ores such as laterites having differing mineral content (e.g., low, medium or high iron content) that provides one or more of the following advantages: low production costs, environmental friendliness, high recovery rates of nickel and / or cobalt, and effective utilization of nickel ore resources.

[0008] Briefly, therefore, one aspect of the present disclosure is the provision of a process for extracting nickel from a feed ore comprising a mineralized form of iron and a mineralized form of nickel, the process comprising (i) treating theBANIQL 3013654.004feed ore with an acid system comprising a source of phosphate and a mineral acid other than phosphoric acid to form a leached ore and a leachate comprising nickel extracted from the phosphoric acid treated ore and (ii) separating the leachate from the leached ore. In one such embodiment, the phosphate source is phosphoric acid.

[0009] A further aspect of the present disclosure is the provision of a process for extracting nickel from a feed ore comprising a mineralized form of iron and a mineralized form of nickel, the process comprising (i) treating the feed ore with an acid system comprising a source of phosphate and a mineral acid other than phosphoric acid at a pressure less than 2 standard atmospheres ( / .e., less than 1520 mm Hg) to form a leached ore and a leachate comprising nickel extracted from the phosphoric acid treated ore and (ii) separating the leachate from the leached ore. In one such embodiment, the phosphate source is phosphoric acid.

[0010] A further aspect of the present disclosure is the provision of a heap leaching process for extracting nickel from a feed ore comprising a mineralized form of iron and a mineralized form of nickel, the process comprising (i) treating the feed ore with an acid system comprising a source of phosphate and a mineral acid other than phosphoric acid to form a leached ore and a leachate comprising nickel extracted from the phosphoric acid treated ore and (ii) separating the leachate from the leached ore. In one such embodiment, the phosphate source is phosphoric acid.[ooii] Without being bound to any particular theory, and based upon experimental evidence obtained to date, the ratio of nickel and / or cobalt relative to iron obtained in the leachate of a hydrometallurgical reaction mixture of the present disclosure may be modulated during a leaching step, at least in part, by the (i) inclusion of a source of phosphate in the reaction mixture (see, e.g., FIGs. 1 and 4), (ii) the inclusion of a source of ammonia / ammonium in the reaction mixture (see, e.g., FIGs. 2 and 5), and / or (iii) controlling the pH of the reaction mixture to a pH value in the range of 0.8 to 4.5; for example, in one such embodiment the pH of the reaction mixture is at a value of 1 to 4.5 (see, e.g., FIGs.3 and 6).

[0012] Other objects and features will be in part apparent and in part pointed out hereinafter.BANIQL 3013654.004BRIEF DESCRIPTION OF THE DRAWINGS

[0013] To facilitate further description of the embodiments of this disclosure, the following drawings are provided to illustrate and not to limit the scope of the disclosure.

[0014] FIG. 1 is a compilation of test results of Examples 1-18 and, more specifically, shows the relationship between (i) the weight ratio of Ni to Fe obtained in leachate and (ii) the pH of the leachate (at the 4 hour mark) under the various experimental conditions.

[0015] FIG. 2 is a compilation of test results of Examples 1-18 and, more specifically, shows the relationship between (i) the weight ratio of Ni to Fe obtained in leachate and (ii) the mole ratio of phosphate to the combined amount of iron and aluminum in the tested ore (prior to leaching) under the various experimental conditions.

[0016] FIG. 3 is a compilation of test results of Examples 1-18 and, more specifically, shows the relationship between (i) the weight ratio of Ni to Fe obtained in leachate and (ii) the mole ratio of the ammonia source in the leachate to nickel in the tested ores (prior to leaching) under the various experimental conditions

[0017] FIG. 4 is a compilation of test results of Examples 1-18 and, more specifically, shows the relationship between (i) the percentage of nickel extracted from the tested ores and (ii) the pH of the leachate (at the 4 hour mark) under the various experimental conditions.

[0018] FIG. 5 is a compilation of test results of Examples 1-18 and, more specifically, shows the relationship between (i) the percentage of nickel extracted from the tested ores and (ii) the mole ratio of phosphate to the combined amount of iron and aluminum in the tested ores (prior to leaching) under the various experimental conditions.

[0019] FIG. 6 is a compilation of test results of Examples 1-18 and, more specifically, shows the relationship between (i) the percentage of the nickel extracted from the tested ores and (ii) the mole ratio of the ammonia source in the leachate to nickel in the tested ore (prior to leaching) under the various experimental conditions.BANIQL 3013654.004DEFINITIONS

[0020] As used herein, the term “acid phosphate” refers to phosphoric acid that has been buffered or partially neutralized by a mineral salt such as calcium, magnesium, potassium or sodium

[0021] As used herein, the term “leachant” refers to a liquid used to leach metals from a nickeliferous ore.

[0022] As used herein, the term “leachate” refers to a leachant that has been combined with an ore and contains components, e.g., nickel, that have been leached from the ore.

[0023] As used herein, the term “mineral acid” is an acid derived from one or more inorganic compounds and includes hydrogen halides, chloric acid, nitric acid, nitrous acid, phosphoric acid, sulfuric acid, boric acid, and perchloric acid.

[0024] As used herein, the term “ore” means a naturally occurring or other solid material from which a metal or valuable mineral can be extracted.

[0025] As used herein and unless otherwise indicated by the context, the term “phosphate” refers to an anion selected from the group consisting of orthophosphate [PO4]3-; hydrogen phosphate [HPO4]2-; or dihydrogen phosphate [H2PO4]-or to a salt or ester of phosphoric acid from which one or more of such anions may be derived. For example, such an anions may be derived by the removal of one, two or three protons from phosphoric acid or from a salt thereof.

[0026] When introducing elements of the present disclosure or the preferred embodiments(s) thereof, the articles "a", "an", "the" and "said" are intended to mean that there are one or more of the elements. The terms "comprising", "including" and "having" are intended to be inclusive and mean that there may be additional elements other than the listed elements.

[0027] As used herein, all percentages are percentages by weight unless otherwise indicated.DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0028] In general, the reaction mixture of a hydrometallurgical process of the present disclosure comprises nickeliferous ore and an aqueous leachant,BANIQL 3013654.004wherein the nickeliferous ore may be any composition, naturally occurring or otherwise, containing nickel and iron and from which nickel may be extracted (i.e., leached). For example, in one embodiment, the nickeliferous ore is a limonite type laterite (or oxide type) that is highly enriched in iron. In another embodiment, the nickeliferous ore is a saprolite laterite (or silicate type) ore. In a further embodiment, the nickeliferous ore is a mixture of limonite and saprolite laterites. In an alternative embodiment, the nickeliferous ore may be a magmatic sulfide, such as pentlandite or a mixture of a magmatic sulfide and an oxide type ore.

[0029] In accordance with one aspect of the present disclosure, the nickeliferous ore is leached with a leachant comprising a phosphate (e.g., phosphoric acid) and an acid system comprising a mineral acid other than phosphoric acid. Exemplary mineral acids include hydracids such as hydrochloric, hydroiodic, hydrobromic, or hydrofluoric acid, or an oxyacid such as sulfuric, nitric, perchloric, or boric acid. In one embodiment, the leachant comprises a mineral acid selected from the group consisting of hydrochloric acid (HCl), sulfuric acid (H2SO4), nitric acid (HNO3), and the combinations thereof. For example, in one such embodiment, the acid system comprises a mineral acid selected from the group consisting of hydrochloric acid, sulfuric acid and a combination thereof. By way of further example, in one such embodiment the acid system comprises sulfuric acid. Although generally less preferred, in addition to at least one of hydrochloric, sulfuric and nitric acids, the acid system may also comprise (i) one or more mineral acids other than hydrochloric, nitric, phosphoric, and sulfuric, (ii) one or more organic acids, e.g., formic, acetic, citric, etc., or (iii) a combination of one or more other mineral acids and one or more organic acids.

[0030] In general, the amount of mineral acid comprised by a reaction mixture is, at least in part, a function of the mineralogy of the ore, the species of mineral acid(s) included in the acid system, and the process parameters of the type of hydrometallurgical process employed. In some embodiments, the concentration of the mineral acid(s) in the reaction mixture will be in the range of 0.01 to 2 M. For example, in one such embodiment, the concentration of the mineral acid(s) in the reaction mixture will be in the range of 0.5 to 1.75 M. In another such embodiment, the concentration of the mineral acid(s) in the reaction mixture will be in the range of 0.75 to 1.5 M. For clarity, when the acid system comprises a single mineral acidBANIQL 3013654.004other than phosphoric acid, e.g., sulfuric acid, the concentration of the mineral acid(s) in the reaction mixture equals the concentration of sulfuric acid in the reaction mixture, and when the acid system comprises a mixture of two or more mineral acids other than phosphoric acid, e.g., sulfuric and hydrochloric acids, the concentration of mineral acid(s) in the reaction mixture equals the sum of the concentrations of sulfuric and hydrochloric acid in the reaction mixture.

[0031] In one embodiment, the reaction mixture comprises an acid system of the present disclosure (e.g., at least one mineral acid other than phosphoric acid) and nickeliferous ore in a weight ratio of at least 1: 100, respectively (weight ratio of mineral acid(s) other than phosphoric acid to nickeliferous ore comprised by the reaction mixture). For example, in heap leaching processes, the reaction mixture may contain the mineral acid(s) other than phosphoric acid and nickeliferous ore in a weight ratio of at least 1: 10 or even at least 1:4. Atmospheric acid leaching processes tend to employ greater amounts of mineral acid; for example, in an atmospheric acid leaching process, the reaction mixture may contain mineral acid other than phosphoric acid and nickeliferous ore in a weight ratio of at least 5: 100, at least 10:100, at least 15:100, at least 20:100, at least 25:100, at least 30:100, at least 35:100, or even at least 40:100, respectively (i.e., weight ratio of mineral acid other than phosphoric acid to nickeliferous ore comprised by the reaction mixture). Typically, however, the weight ratio of mineral acid other than phosphoric acid to nickeliferous ore comprised by the reaction mixture in an atmospheric leaching process will be less than 1:2, respectively.

[0032] As exemplified herein, selectivity for nickel and / or cobalt over iron may be increased in a reaction mixture containing (i) phosphoric acid, and (ii) at least one mineral acid other than phosphoric acid wherein the mineral acid(s) other than phosphoric are the predominant acid. Stated differently, selectivity for nickel and / or cobalt over iron may be increased by treating the ore with an acid system comprising phosphoric acid but in which the amount of phosphoric acid comprised by the acid system is less than 50 wt% of the total combined amount of acids comprised by the acid system. For example, in one such embodiment, the acid system comprises phosphoric acid and the weight ratio of acids other than phosphoric acid to the amount of phosphoric acid comprised by the acid system exceeds 1:1, respectively. By way of further example in one embodiment, the acid system comprisesBANIQL 3013654.004phosphoric acid and the weight ratio of acids other than phosphoric acid to the amount of phosphoric acid comprised by the acid system exceeds 2:1. By way of further example in one embodiment, the acid system comprises phosphoric acid and the weight ratio of acids other than phosphoric acid to the amount of phosphoric acid comprised by the acid system exceeds 2.5:1. By way of further example in one embodiment, the acid system comprises phosphoric acid and the weight ratio of acids other than phosphoric acid to the amount of phosphoric acid comprised by the acid system exceeds, 3:1. By way of further example in one embodiment, the acid system comprises phosphoric acid and the weight ratio of acids other than phosphoric acid to the amount of phosphoric acid comprised by the acid system exceeds 3.5:1. By way of further example in one embodiment, the acid system comprises phosphoric acid and the weight ratio of acids other than phosphoric acid to the amount of phosphoric acid comprised by the acid system exceeds 4:1. By way of further example in one embodiment, the acid system comprises phosphoric acid and the weight ratio of acids other than phosphoric acid to the amount of phosphoric acid comprised by the acid system exceeds 4.5:1. By way of further example in one embodiment, the acid system comprises phosphoric acid and the weight ratio of acids other than phosphoric acid to the amount of phosphoric acid comprised by the acid system exceeds 5:1. By way of further example in one embodiment, the acid system comprises phosphoric acid and the weight ratio of acids other than phosphoric acid to the amount of phosphoric acid comprised by the acid system exceeds 5.5:1. By way of further example in one embodiment, the acid system comprises phosphoric acid and the weight ratio of acids other than phosphoric acid to the amount of phosphoric acid comprised by the acid system exceeds 6:1, respectively. In general, however, the weight ratio of acids other than phosphoric acid to the amount of phosphoric acid comprised by the acid system is less than 10:1 and, in some embodiments is less than 9:1, 8:1, 7:1, or even 6:1, respectively.

[0033] In general, the reaction mixture of the present disclosure may comprise any of a range of phosphate sources. In one embodiment, the phosphate source is phosphoric acid. In another embodiment, the phosphate source is a phosphate salt, e.g., an inorganic phosphate salt. Exemplary inorganic phosphate salts include sodium phosphate salts (e.g., mono, di or trisodium phosphate),BANIQL 3013654.004potassium phosphate salts (e.g., mono, di or tripotassium phosphate), calcium phosphate salts (e.g., dicalcium or tricalcium phosphate or hydroxapetite), ammonium phosphate salts (e.g., mono, di or triammonium phosphate), ammonium calcium phosphate, magnesium phosphate salts (e.g., di or trimagnesium phosphate), mixed anion phosphates (e.g., phosphate sulfates), superphosphates (e.g., single superphosphate or triple superphosphate), other phosphate-bearing compositions or naturally occurring minerals, or combinations thereof. For example, in one such embodiment the reaction mixture comprises a phosphate source selected from the group consisting of phosphoric acid, ammonium phosphate salts, ammonium calcium phosphate, magnesium phosphate salts, mixed anion phosphates, superphosphates and combinations thereof and a mineral acid selected from the group consisting of hydrochloric acid and sulfuric acid and combinations thereof. By way of further example, in one such embodiment the reaction mixture comprises a phosphate source selected from the group consisting of phosphoric acid, monoammonium phosphate, diammonium phosphate, single superphosphate, and triple superphosphate.

[0034] In general, the amount of phosphate comprised by a reaction mixture of the present disclosure is, at least in part, a function of the mineralogy of the ore, the phosphate source, and the parameters of the hydrometallurgical process employed. In some embodiments, the concentration of phosphate in the reaction mixture will be in the range of 0.01 to 1 M. For example, in one such embodiment, the concentration of phosphate in the reaction mixture will be in the range of 0.05 to 0.5 M. In another such embodiment, the concentration of phosphate in the reaction mixture will be in the range of 0.1 to 0.35 M. For clarity, when the acid system comprises a single phosphate source, e.g., phosphoric acid, the concentration of phosphate in the reaction mixture equals the concentration of phosphoric acid in the reaction mixture, and when the acid system comprises a mixture of two or more phosphate sources, e.g., phosphoric acid and diammonium phosphate, the concentration of phosphate in the reaction mixture equals the sum of the concentrations of phosphoric acid and diammonium phosphate in the reaction mixture.

[0035] In one embodiment, the amount of phosphate in the reaction mixture is proportional to the amount of iron comprised by the nickeliferous ore in theBANIQL 3013654.004reaction mixture. For example, in one such embodiment the molar ratio of phosphate to iron (comprised by the nickeliferous ore) in the reaction is at least 1:50, respectively. By way of further example, in one such embodiment the molar ratio of phosphate to iron (comprised by the nickeliferous ore) in the reaction mixture is at least 1:40, at least 1:30, at least 1:20, at least 1:10, at least 1:7.5, at least 1:5, at least 1:4, at least 1:3, at least 1:2, or even at least 1:1, respectively (i.e., moles of phosphate to moles of iron in the nickeliferous ore comprised by the reaction mixture); typically, however, the molar ratio of phosphate to iron (comprised by the nickeliferous ore) in the reaction mixture will be less than 1:5, respectively. By way of further example, the molar ratio of phosphate to iron (comprised by the nickeliferous ore) in the reaction mixture will typically be less than 1:6, less than 1:7, or even less than 1:10, respectively (i.e., moles of phosphate to moles of iron in the nickeliferous ore comprised by the reaction mixture).

[0036] In one embodiment, the amount of phosphate in the reaction mixture is proportional to the combined amount of iron and aluminum comprised by the nickeliferous ore in the reaction mixture. For example, in one such embodiment the molar ratio of phosphate to the combined amount of iron and aluminum (comprised by the nickeliferous ore) in the reaction is at least 1:50, respectively. By way of further example, in one such embodiment the molar ratio of phosphate to the combined number of moles of iron and aluminum (comprised by the nickeliferous ore) in the reaction mixture is at least 1:40, at least 1:30, at least 1:20, at least 1:10, at least 1:7.5, at least 1:5, at least 1:4, at least 1:3, at least 1:2, or even at least 1:1, respectively (i.e., moles of phosphate to the combined number of moles of iron and aluminum in the nickeliferous ore comprised by the reaction mixture); typically, however, the molar ratio of phosphate to the combined number of moles of iron and aluminum (comprised by the nickeliferous ore) in the reaction mixture will be less than 1:5, respectively. By way of further example, the molar ratio of phosphate to the combined number of moles of iron and aluminum (comprised by the nickeliferous ore) in the reaction mixture will typically be less than 1:6, less than 1:7, or even less than 1:10, respectively (i.e., moles of phosphate to combined number of moles of iron and aluminum in the nickeliferous ore comprised by the reaction mixture).

[0037] In one embodiment, the reaction mixture optionally comprises a source of ammonium. In one embodiment, the ammonium source is an ammoniumBANIQL 3013654.004base or an ammonium salt. For example, in one such embodiment the ammonium source is an ammonium base such as ammonia or ammonium hydroxide. In another embodiment, the ammonium source is an organic or inorganic ammonium salt such as ammonium phosphate (e.g., mono, di or triammonium phosphate), ammonium calcium phosphate, ammonium chloride, ammonium sulfate, ammonium nitrate, or a combination thereof. Typically, the concentration of the ammonium source in the reaction mixture will be in the range of 0.01 to 1 M. For example, in one such embodiment, the concentration of the ammonium source in the reaction mixture will be in the range of 0.05 to 0.75 M. In another such embodiment, the concentration of ammonium source in the reaction mixture will be in the range of 0.075 to 0.5 M. For clarity, when the reaction mixture comprises a single ammonium source, e.g., ammonia, the concentration of ammonium in the reaction mixture equals the concentration of ammonia in the reaction mixture, and when the reaction mixture comprises a mixture of two or more ammonium sources, e.g., ammonia and diammonium phosphate, the concentration of ammonium in the reaction mixture equals the sum of the concentrations of ammonia and diammonium phosphate in the reaction mixture.

[0038] In one embodiment, the amount of ammonium source in the reaction mixture is proportional to the amount of nickel comprised by the nickeliferous ore in the reaction mixture. For example, in one such embodiment the molar ratio of ammonium source to nickel (comprised by the nickeliferous ore) in the reaction is at least 0.5:1, respectively. By way of further example, in one such embodiment the molar ratio of ammonium to nickel (comprised by the nickeliferous ore) in the reaction mixture is at least 0.75:1, at least 1:1, at least 2:1, at least 3:1, at least 5:1, at least 10:1, or even at least 15:1, respectively (i.e., moles of ammonium to moles of nickel in the nickeliferous ore comprised by the reaction mixture); typically, however, the molar ratio of ammonium to nickel (comprised by the nickeliferous ore) in the reaction mixture will be less than 15:1, respectively. By way of further example, the molar ratio of ammonium to nickel (comprised by the nickeliferous ore) in the reaction mixture will typically be less than 10:1, less than 5:1, less than 2:1, or even less than 1:1, respectively (i.e., moles of ammonium to moles of nickel in the nickeliferous ore comprised by the reaction mixture).BANIQL 3013654.004

[0039] As previously noted, the ratio of nickel and / or cobalt to iron in the leachate resulting from a hydrometallurgical process of the present disclosure may also be influenced, at least in part, by the pH of the reaction mixture. In general, and based upon experimental evidence to date, selectivity for nickel tends to increase as a function of increasing pH for pH values within the range of pH 1 to pH 4.5. For example, in one embodiment the pH of the reaction mixture is at least pH 1.5, at least pH 1.8, at least pH 2, at least pH 2.2, at least pH 2.4, at least pH 2.6, at least pH 2.8, or even at least pH 3. Typically, however, the pH of the reaction mixture will be less than pH 5; for example, the pH of the reaction mixture in some embodiments will be less than pH 4.5, less than pH 4, or even less than pH 3.5. The pH may adjusted, for example, by addition of acids or bases to the reaction mixture that adjust the pH to a value in excess of pH 1. Exemplary acids and bases include hydroxide bases such as sodium hydroxide, potassium hydroxide or calcium hydroxide, carbonate bases such as calcium carbonate, sodium carbonate and sodium bicarbonate, acidic ammonium salts such as ammonium chloride, ammonium nitrate, and ammonium sulfate, and ammonium hydroxide.

[0040] In one embodiment, prior to the leaching step the process of the present disclosure involves classifying the ore into separate fractions, based upon (i) particle size, (ii) iron or other elemental or mineral content, and / or (iii) ore type, e.g., limonite and saprolite fractions. For example, the ore may be sieved to separate the ore into multiple fractions based upon size, e.g., a > 2.5 cm fraction, a 500-2,000 pm fraction and a less than 500 pm fraction. Alternatively, or additionally, the ore may be divided into two or more fractions based upon iron content, e.g., a fraction having an iron content of > 25 wt% iron and a fraction containing less than 25 wt% iron. Alternatively, or additionally, the ore may be separated into limonite and saprolite fractions.

[0041] In certain embodiments, the ore is subjected to a particle size reduction step prior to leaching. For example, the ore may be fed to a unit such as a crusher, shredder, grinder, pulverizer, jet mill, pin mill, or ball mill to adjust the ore particle size. For example, in one such embodiment, the ore will have a particle size of greater than 2.5 cm after the particle size reduction step. By way of further example, in one such embodiment, the ore will have a particle size of less than 2.5 cm after the particle size reduction step. By way of further example, in one suchBANIQL 3013654.004embodiment, the ore will have a particle size of less than 1 cm after the particle size reduction step. By way of further example, in one such embodiment, the ore will have a particle size of less than 5000 micrometers after the size reduction step. By way of further example, in one such embodiment the ore will have a particle size of less than 3350 micrometers (US Standard Sieve 6 mesh) after the size reduction step. By way of further example, in one such embodiment the ore will have a particle size of less than 2820 micrometers (US Standard Sieve 7 mesh) after the size reduction step. By way of further example, in one such embodiment, the ore will have a particle size of less than 2380 micrometers (US Standard Sieve 8 mesh) after the particle size reduction step. By way of further example, in one such embodiment, the ore will have a particle size of less than 2000 micrometers (US Standard Sieve 10 mesh) after the particle size reduction step. By way of further example, in one such embodiment, the ore will have a particle size of less than 1680 micrometers (US Standard Sieve 12 mesh) after the particle size reduction step. By way of further example, in one such embodiment, the ore will have a particle size of less than 1410 micrometers (US Standard Sieve 14 mesh) after the particle size reduction step. By way of further example, in one such embodiment, the ore will have a particle size of less than 1000 micrometers (US Standard Sieve 18 mesh) after the particle size reduction step. In general, the ore will have a particle size of at least 105 micrometers (US Standard Sieve 140 mesh), at least 125 micrometers (US Standard Sieve 120 mesh), or even at least 149 micrometers (US Standard Sieve 100 mesh). For example, in certain embodiments, the ore will have a particle size in the range of 125-250 micrometers (+120 mesh / -60 mesh US Standard Sieve), or even in the range of 500-2,000 micrometers (+35 mesh / -10 mesh US Standard Sieve). In general, the ore will have a particle size of at least 125 micrometers (US Standard Sieve 1),

[0042] In certain embodiments, the ore has been subjected to a reductive roast or a calcining roast prior to leaching. For example, the ore may be roasted in a rotary kiln at a temperature in the range of 300 °C to about 800 °C.BANIQL 3013654.004Low Pressure Leaching

[0043] In one embodiment, the leaching step is carried out at low pressure (< 2 standard atmospheres), e.g., atmospheric pressure, and a temperature less than 120 °C, e.g., a temperature in the range of 80 °C to 100 °C. As previously noted, the low-pressure leaching process of present disclosure may be used to recover nickel and / or cobalt from ores containing oxide minerals such as limonitetype laterite ores, and / or ores containing silicate minerals such as saprolites.Limonite-type laterites tend to be highly enriched in iron due to the environmental leaching of magnesium and silica and typically contain at least about 25 wt% iron. In contrast, saprolite-type laterite ores typically contain greater amounts of magnesium and silica and relatively lesser amounts of iron, generally ranging from 5 to 20 wt% Fe. Irrespective of whether the ore is characterized as limonite, saprolite, or lateritic, the process of the present disclosure may be used to recovery nickel and / or cobalt from nickel and / or cobalt containing ores also containing at least 2.5 wt% iron, 5 wt% iron, at least 10 wt% iron, at least 15 wt% iron, at least 20 wt% iron, at least 25 wt% iron, at least 30 wt% iron, at least 35 wt% iron, or even at least 40 wt% iron.

[0044] In certain embodiments, the feed ore is classified by (i) size, (ii) iron or other elemental or mineral content, and / or (iii) ore type, or calcined as previously discussed and combined with an acid system in reaction vessel with agitation. In certain embodiments, the feed ore is leached in stages, e.g., in a first stage with a first acid system in a reaction vessel and then in a second stage with a second acid system in the same or different reaction vessel. For example, in one such embodiment the ore is treated in a first stage with a reaction mixture comprising a first acid system wherein phosphoric acid is the predominant mineral acid and in a second stage in a second reaction mixture comprising a second acid system in which mineral acid(s) other than phosphoric acid, in combination, are the predominant mineral acid. Stated differently, in one such embodiment the weight ratio of phosphoric acid in the first acid system to the combined amount of mineral acid(s) other than phosphoric acid comprised by the first acid system exceeds 1:1, respectively, and the weight ratio of phosphoric acid in the second acid system to the combined amount of mineral acid(s) other than phosphoric acid comprised by the second acid system is less than 1:1, respectively. By way of further example in one such embodiment the weight ratio of phosphoric acid in the first acid system to theBANIQL 3013654.004combined amount of mineral acid(s) other than phosphoric acid comprised by the first acid system exceeds 2:1, and the weight ratio of phosphoric acid in the second acid system to the combined amount of mineral acid(s) other than phosphoric acid comprised by the second acid system is less than 1:1, 3:1, 4:1, 5:1, or even 10:1, respectively. By way of further example in one such embodiment the weight ratio of phosphoric acid in the first acid system to the combined amount of mineral acids other than phosphoric acid comprised by the first acid system exceeds 3:1 and the weight ratio of phosphoric acid in the second acid system to the combined amount of mineral acids other than phosphoric acid comprised by the second acid system in the subsequent stage is less than 1: 1, 3: 1, 4: 1, 5: 1, or even 10:1, respectively. By way of further example in one such embodiment the weight ratio of phosphoric acid in the first acid system to the combined amount of mineral acid(s) other than phosphoric acid comprised by the first acid system exceeds 4:1 and the weight ratio of phosphoric acid in the second acid system to the combined amount of mineral acid(s) other than phosphoric acid comprised by the second acid system in the subsequent stage is less than 1:1, 3:1, 4:1, 5:1, or even 10:1. By way of further example in one such embodiment the weight ratio of phosphoric acid in the first acid system to the combined amount of mineral acid(s) other than phosphoric acid comprised by the first acid system in the first stage exceeds 5:1 and the weight ratio of phosphoric acid in the second acid system to the combined amount of mineral acid(s) other than phosphoric acid comprised by the acid system in the subsequent stage is less than 1:1, 3:1, 4:1, 5:1, or even 10:1. By way of further example in one such embodiment the weight ratio of phosphoric acid in the first acid system to the combined amount of mineral acid(s) other than phosphoric acid comprised by the first acid system in the first stage exceeds 6:1 and the weight ratio of phosphoric acid in the second acid system to the combined amount of mineral acid(s) other than phosphoric acid comprised by the second acid system in the subsequent stage is less than 1:1, 3:1, 4:1, 5:1, or even 10:1, respectively. By way of further example in one such embodiment the weight ratio of phosphoric acid in the first acid system to the combined amount of mineral acid(s) other than phosphoric acid comprised by the first acid system in the first stage exceeds 10:1 and the weight ratio of phosphoric acid in the second acid system to the combined amount of mineral acid(s) other than phosphoric acid comprised by the second acid system in the subsequent stage is less than 1: 1, 3: 1, 4: 1, 5: 1, or even 10:1, respectively.BANIQL 3013654.004

[0045] In general, the amount of phosphoric acid employed in the first reaction mixture is sufficient to convert at least a portion of mineralized iron comprised by the ore into iron oxide phosphate phases that are sparingly soluble in subsequent acid extractions relative to nickel. For example, in one such embodiment, the weight ratio of phosphoric acid to ore in the first reaction mixture will be at least 1:100, respectively. By way of further example, in one such embodiment the weight ratio of phosphoric acid to ore in the first reaction mixture will be at least 1:50, respectively. By way of further example, in one such embodiment the weight ratio of phosphoric acid to ore in the first reaction mixture will be at least 2:50 (i.e., at least 1:25), respectively. By way of further example, in one such embodiment the weight ratio of phosphoric acid to ore in the first reaction mixture will be at least 1:20, respectively. By way of further example, in one such embodiment the weight ratio of phosphoric acid to ore in the first reaction mixture will be at least 1:10, respectively. By way of further example, in one such embodiment the weight ratio of phosphoric acid to ore in the first reaction mixture will be at least 1:5, respectively. In general, however, the weight ratio of phosphoric acid to ore in the first reaction mixture will not exceed 1:5, respectively. For example, in one such embodiment the weight ratio of phosphoric acid to ore in the first reaction mixture will not exceed in 1:7.5, respectively. By way of further example, in one such embodiment the weight ratio of phosphoric acid to ore in the first reaction mixture will not exceed 1:10, respectively. By way of further example, in one such embodiment the weight ratio of phosphoric acid to ore in the first reaction mixture will not exceed 1:15, respectively. By way of further example, in one such embodiment the weight ratio of phosphoric acid to ore in the first reaction mixture will not exceed 1:20, respectively.

[0046] In general, the combined amount of mineral acids other than phosphoric acid, e.g., hydrochloric acid, sulfuric acid, nitric acid, or combinations thereof in the second reaction mixture is sufficient to dissolve at least a portion of mineralized nickel and / or cobalt comprised by the ore as the corresponding salt into the leachate while leaving behind insoluble iron oxide phosphate phases. For example, in one such embodiment, the weight ratio of the combined amount of mineral acids other than phosphoric acid in the second reaction mixture will be at least 1:1, respectively. By way of further example, in one such embodiment theBANIQL 3013654.004weight ratio of the combined amount of mineral acids other than phosphoric acid in the second reaction mixture will be at least 2:1, respectively. By way of further example, in one such embodiment the weight ratio of the combined amount of mineral acids other than phosphoric acid in the second reaction mixture will be at least 3: 1, respectively. By way of further example, in one such embodiment the weight ratio of the combined amount of mineral acids other than phosphoric acid in the second reaction mixture will be at least 4:1, respectively. By way of further example, in one such embodiment the weight ratio of the combined amount of mineral acids other than phosphoric acid in the second reaction mixture will be at least at least 5:1, respectively. In general, however, the weight ratio of the combined amount of mineral acids other than phosphoric acid in the second reaction mixture will not be in excess of 10:1, respectively. For example, in one such embodiment the weight ratio of the combined amount of mineral acids other than phosphoric acid in the second reaction mixture will not be in excess of 9:1, respectively. By way of further example, in one such embodiment the weight ratio of the combined amount of mineral acids other than phosphoric acid in the second reaction will not be in excess of 8:1, respectively. By way of further example, in one such embodiment the weight ratio of the combined amount of mineral acids other than phosphoric acid in the second reaction will not be in excess of 7:1, respectively. By way of further example, in one such embodiment the weight ratio of the combined amount of mineral acids other than phosphoric acid in the second reaction will not be in excess of 6:1, respectively.

[0047] In certain embodiments, the ore is leached in a single stage wherein the acid system in this single stage compositionally comprises phosphoric acid (or other phosphate source) and a mineral acid other than phosphoric acid as previously described. For example, in one such embodiment the weight ratio of phosphoric acid in the acid system to mineral acids other than phosphoric acid comprised by the acid system is in the range of 1: 10 and 1:2. By way of further example, in one such embodiment the weight ratio of phosphoric acid to the combined amounts of mineral acids other than phosphoric acid is in the range of 1:7.5 and 1:2.5, respectively. By way of further example, in one such embodiment the weight ratio of phosphoric acid to the combined amounts of mineral acids other than phosphoric acid is in the range of 1:6 and 1:3, respectively. By way of furtherBANIQL 3013654.004example, in one such embodiment the weight ratio of phosphoric acid to the combined amounts of mineral acids other than phosphoric acid is in the range of 1:5 and 1:3, respectively.

[0048] Regardless of the number of stages, it is generally preferred that the reaction mixtures be under a relatively low-pressure atmosphere. For example, in one embodiment, the first and / or second reaction mixtures are under an atmosphere having a pressure of less than 2 standard atmospheres ( / .e., less than 1520 mm Hg). By way of further example, in one such embodiment the first and / or second reaction mixtures are under an atmosphere having a pressure of less than 1.75 standard atmospheres. By way of further example, in one such embodiment the first and / or second reaction mixtures are under an atmosphere having a pressure of less than 1.5 standard atmospheres. By way of further example, in one such embodiment the first and / or second reaction mixtures are under an atmosphere having a pressure of less than 1.25 standard atmospheres. By way of further example, in one such embodiment the first and / or second reaction mixtures are under an atmosphere having a pressure of less than 1.1 standard atmospheres. By way of further example, in one such embodiment the first and / or second reaction mixtures are under an atmosphere having a pressure of not in excess of 1 standard atmospheres (i.e., 760 mm Hg), e.g., ambient atmospheric pressure.

[0049] In general, and independent of the number of stages, it is generally preferred that the leaching reaction(s) be carried out a temperature less than boiling point of the reaction mixture. For example, it is generally preferred that the first and / or second reaction mixtures be at a temperature not in excess of 120 °C. By way of further example, it is generally preferred that the first and / or second reaction mixtures be at a temperature not in excess of 110 °C. By way of further example, it is generally preferred that the first and / or second reaction mixtures be at a temperature not in excess of 100 °C. By way of further example, it is generally preferred that the first and / or second reaction mixtures be at a temperature not in excess of 95 °C. By way of further example, it is generally preferred that the first and / or second reaction mixtures be at a temperature not in excess of 90 °C. By way of further example, in certain embodiments the first and / or second reaction mixtures are at a temperature in the range of 60 to 100 °C, more typically in the range of 70 °C to 95 °C.BANIQL 3013654.004

[0050] After leaching for a period of time, the leached solids are separated from the leachate. In certain embodiments, a cationic flocculent may be added to the reaction mixture to consolidate the solids to ease separation.Heap Leaching

[0051] In one embodiment, the ore is subjected to heap leaching. In general, heap leaching provides a low-cost method for extracting metal values from relatively low-grade metal-bearing materials and has found particular application in the processing of nickeliferous ores. During mining, the nickeliferous material, also referred to herein as feed ore, may progress through multiple stages as it is extracted, transported, and processed. In one embodiment, the feed ore may be classified by (i) size, (ii) iron or other elemental or mineral content, and / or (iii) ore type, or calcined as previously discussed, prior to leaching. Alternatively, the feed ore, as extracted at the mining site and leached as run-of-mine ore; that is, ore that is produced by, for example, blasting, open pit mining, and other surface and subterranean ore extraction techniques without further treatment prior to leaching.

[0052] Run-of-mine (or “ROM”) ore includes ore of various sizes from ore as small as powder up to and including boulders. After mining, the ROM ore is transported to a heap location where it is stacked onto an impervious pad without any intermediary extraction enhancement treatments, such as crushing or agglomeration. This lack of energy intensive pre-treatment renders ROM heap leaching a low-cost processing method relative to other mineral processing methods such as crushed ore heap leaching.

[0053] Independent of whether the ore is ROM ore or has otherwise been classified or calcined, an acid system is dispensed onto the heap to dissolve the metal ions from readily soluble minerals to form a nickel-bearing leachate. The nickel-bearing leachate trickles (percolates) slowly through the heap under the force of gravity until it reaches a collection pad or other collection device at the base of the heap. The collection device or pad typically has a sloped base to allow the leachate to flow into collection drains, which discharge the leachate into a leach pond or tank, for further processing, such as by conventional, solvent extraction / electrowinning (SX / EW) or direct electrowinning (DEW).BANIQL 3013654.004

[0054] For effective metal extraction, the ore is preferably leached for an amount of time, typically ranging from several weeks to several months, or more. After the ore has been leached for a sufficient period, the flow of acid onto the heap is shut off and the leach pad may be allowed to partially dry out. Optimization of leach heaps typically involves constant monitoring as many variables are preferably controlled to maximize metal recovery, including acid content, permeability, particle size distribution, temperature, and oxygen content and, as the slow kinetics of leaching reactions occur over an extended period, monitoring and prediction models are beneficial for the success of the leaching process.Neutralization

[0055] Following leaching, the pH of the leachate may be adjusted and a neutralized precipitate containing impurity elements is separated to thereby obtain a post-neutralization solution containing nickel and / or cobalt. More specifically, in the neutralization step, neutralizers such as limestone and / or hydrogen peroxide may be added to the leachate to neutralize the surplus acid in the leachate while the oxidation of the separated leachate is suppressed such that the pH of the postneutralization solution obtained is adjusted to 4 or less, preferably 3.0 to 3.5, and more preferably 3.1 to 3.2, and impurity components such as trivalent iron and aluminum in the leachate are obtained as a neutralized precipitate. In the neutralization step, the neutralized precipitate generated in this way is subjected to sedimentation and separation to generate a post-neutralization solution serving as a mother liquor for recovering nickel.

[0056] Following neutralization, electrolytic nickel and / or cobalt may be obtained by electrowinning, using a neutralized solution containing the separated leachates which, in turn, contain sulfates or other salts of nickel and / or cobalt.Preferably, the electrowinning process is tuned to maintain impurity metals such as magnesium and manganese in the neutralized solution during electrowinning.Alternatively, nickel and / or cobalt may be coprecipitated by adding sodium hydroxide to obtain a mixed hydroxide precipitate.

[0057] In further embodiments, enumerated as Embodiments 1 - 131 below, the present disclosure comprises the following.BANIQL 3013654.004

[0058] Embodiment 1. A process for extracting nickel from a feed ore comprising a mineralized form of iron and a mineralized form of nickel, the process comprising (i) treating the feed ore with a leachant in a reaction mixture to form a leached ore and a leachate comprising nickel extracted from the ore wherein the leachant comprises a phosphate and an acid system, the acid system comprising a mineral acid other than phosphoric acid, and (ii) separating the leachate from the leached ore.

[0059] Embodiment 2. The process of Embodiment 1 wherein the process is carried out at a pressure of less than 2 standard atmospheres.

[0060] Embodiment 3. The process of Embodiment 1 wherein the process is carried out at a pressure of at least 2 standard atmospheres.

[0061] Embodiment 4. The process of Embodiment 1 wherein the process is a heap leaching process in which the acid system is dispersed onto a heap of the feed ore and the nickel-bearing leachate trickles (percolates) slowly through the heap under the force of gravity until it reaches a collection pad or other collection device at the base of the heap.

[0062] Embodiment 5. The process of Embodiment 1 wherein the process is an agitated atmospheric process carried out in a reaction vessel.

[0063] Embodiment 6. The process of any of Embodiments 1 - 5 wherein the weight ratio of the combined amount of mineral acid(s) other than phosphoric acid comprised by the acid system to the amount of phosphoric acid comprised by the acid system is greater than 1:1, respectively.

[0064] Embodiment 7. The process of any of Embodiments 1 - 5 wherein the weight ratio of the combined amount of mineral acid(s) other than phosphoric acid comprised by the acid system to the amount of phosphoric acid comprised by the acid system is greater than 1.5:1, respectively.

[0065] Embodiment 8. The process of any of Embodiments 1 - 5 wherein the weight ratio of the combined amount of mineral acid(s) other than phosphoric acid comprised by the acid system to the amount of phosphoric acid comprised by the acid system is greater than 2:1, respectively.BANIQL 3013654.004

[0066] Embodiment 9. The process of any of Embodiments 1 - 5 wherein the weight ratio of the combined amount of mineral acid(s) other than phosphoric acid comprised by the acid system to the amount of phosphoric acid comprised by the acid system is greater than 2.5:1, respectively.

[0067] Embodiment 10. The process of any of Embodiments 1 - 5 wherein the weight ratio of the combined amount of mineral acid(s) other than phosphoric acid comprised by the acid system to the amount of phosphoric acid comprised by the acid system is greater than 3:1, respectively.

[0068] Embodiment 11. The process of any of Embodiments 1 - 5 wherein the weight ratio of the combined amount of mineral acid(s) other than phosphoric acid comprised by the acid system to the amount of phosphoric acid comprised by the acid system is greater than 4:1, respectively.

[0069] Embodiment 12. The process of any of Embodiments 1 - 5 wherein the weight ratio of the combined amount of mineral acid(s) other than phosphoric acid comprised by the acid system to the amount of phosphoric acid comprised by the acid system is greater than 5:1, respectively.

[0070] Embodiment 13. The process of any previous enumerated Embodiment wherein the weight ratio of the combined amount of mineral acid(s) other than phosphoric acid comprised by the acid system to the amount of phosphoric acid comprised by the acid system is less than 10:1, respectively.

[0071] Embodiment 14. The process of any previous enumerated Embodiment wherein the weight ratio of the combined amount of mineral acid(s) other than phosphoric acid comprised by the acid system to the amount of phosphoric acid comprised by the acid system is less than 9:1, respectively.

[0072] Embodiment 15. The process of any previous enumerated Embodiment wherein the weight ratio of the combined amount of mineral acid(s) other than phosphoric acid comprised by the acid system to the amount of phosphoric acid comprised by the acid system is less than 8:1, respectively.

[0073] Embodiment 16. The process of any previous enumerated Embodiment wherein the weight ratio of the combined amount of mineral acid(s) other than phosphoric acid comprised by the acid system to the amount of phosphoric acid comprised by the acid system is less than 7:1, respectively.BANIQL 3013654.004

[0074] Embodiment 17. The process of any previous enumerated Embodiment wherein the weight ratio of the combined amount of mineral acid(s) other than phosphoric acid comprised by the acid system to the amount of phosphoric acid comprised by the acid system is less than 6:1, respectively.

[0075] Embodiment 18. The process of any previous enumerated Embodiment wherein the weight ratio of the combined amount of mineral acid(s) other than phosphoric acid comprised by the acid system to the amount of phosphoric acid comprised by the acid system is less than 5:1, respectively.

[0076] Embodiment 19. The process of any previous enumerated Embodiment wherein the weight ratio of phosphoric acid to feed ore in the reaction mixture is at least 1: 100, respectively.

[0077] Embodiment 20. The process of any previous enumerated Embodiment wherein the weight ratio of phosphoric acid to feed ore in the reaction mixture is at least 1:50, respectively.

[0078] Embodiment 21. The process of any previous enumerated Embodiment wherein the weight ratio of phosphoric acid to feed ore in the reaction mixture is at least 1:25, respectively.

[0079] Embodiment 22. The process of any previous enumerated Embodiment wherein the weight ratio of phosphoric acid to feed ore in the reaction mixture is at least 1:20, respectively.

[0080] Embodiment 23. The process of any previous enumerated Embodiment wherein the weight ratio of phosphoric acid to feed ore in the reaction mixture is at least 1:10, respectively.

[0081] Embodiment 24. The process of any previous enumerated Embodiment wherein the weight ratio of phosphoric acid to feed ore in the reaction mixture is at least 1:5, respectively.

[0082] Embodiment 25. The process of any previous enumerated Embodiment wherein the weight ratio of phosphoric acid to feed ore in the reaction mixture does not exceed 1:5, respectively.BANIQL 3013654.004

[0083] Embodiment 26. The process of any previous enumerated Embodiment wherein the weight ratio of phosphoric acid to feed ore in the reaction mixture does not exceed 1:7.5, respectively.

[0084] Embodiment 27. The process of any previous enumerated Embodiment wherein the weight ratio of phosphoric acid to feed ore in the reaction mixture does not exceed 1:10, respectively.

[0085] Embodiment 28. The process of Embodiments 1-14 wherein the weight ratio of phosphoric acid to feed ore in the reaction mixture does not exceed 1:15, respectively.

[0086] Embodiment 29. The process of Embodiments 1-14 wherein the weight ratio of phosphoric acid to feed ore in the reaction mixture does not exceed 1:20, respectively.

[0087] Embodiment 30. The process of any previous enumerated Embodiment wherein the mineral acids other than phosphoric acid comprised by the acid system are selected from the group consisting of hydrochloric acid, nitric acid, sulfuric acid and combinations thereof.

[0088] Embodiment 31. The process of any previous enumerated Embodiment wherein the mineral acids other than phosphoric acid comprised by the acid system are selected from the group consisting of hydrochloric acid, sulfuric acid and combinations thereof.

[0089] Embodiment 32. The process of any previous enumerated Embodiment wherein the mineral acids other than phosphoric acid comprised by the acid system is sulfuric acid.

[0090] Embodiment 33. The process of any previous enumerated Embodiment wherein the feed ore comprises at least 5 wt% iron.

[0091] Embodiment 34. The process of any previous enumerated Embodiment wherein the feed ore comprises at least 10 wt% iron.

[0092] Embodiment 35. The process of any previous enumerated Embodiment wherein the feed ore comprises at least 15 wt% iron.

[0093] Embodiment 36. The process of any previous enumerated Embodiment wherein the feed ore comprises at least 20 wt% iron.BANIQL 3013654.004

[0094] Embodiment 37. The process of any previous enumerated Embodiment wherein the feed ore comprises at least 25 wt% iron.

[0095] Embodiment 38. The process of any previous enumerated Embodiment wherein the feed ore comprises at least 30 wt% iron.

[0096] Embodiment 39. The process of any previous enumerated Embodiment wherein the feed ore comprises at least 35 wt% iron.

[0097] Embodiment 40. The process of any previous enumerated Embodiment wherein the feed ore comprises at least 40 wt% iron.

[0098] Embodiment 41. The process of any previous enumerated Embodiment wherein the feed ore comprises at least 45 wt% iron.

[0099] Embodiment 42. The process of any previous enumerated Embodiment wherein the feed ore comprises no more than 3.5 wt% nickel.

[0100] Embodiment 43. The process of any previous enumerated Embodiment wherein the feed ore comprises no more than 3 wt% nickel.

[0101] Embodiment 44. The process of any previous enumerated Embodiment wherein the feed ore comprises no more than 2.5 wt% nickel.

[0102] Embodiment 45. The process of any previous enumerated Embodiment wherein the feed ore comprises no more than 2 wt% nickel.

[0103] Embodiment 46. The process of any previous enumerated Embodiment wherein the feed ore comprises no more than 1.5 wt% nickel.

[0104] Embodiment 47. The process of any previous enumerated Embodiment wherein the feed ore comprises no more than 1 wt% nickel.

[0105] Embodiment 48. The process of any previous enumerated Embodiment wherein the feed ore comprises at least 0.25 wt% nickel.

[0106] Embodiment 49. The process of any previous enumerated Embodiment wherein the feed ore comprises at least 0.5 wt% nickel.

[0107] Embodiment 50. The process of any previous enumerated Embodiment wherein the feed ore has a particle size greater than 2.5 cm.BANIQL 3013654.004

[0108] Embodiment 51. The process of any previous enumerated Embodiment wherein the feed ore has a particle size less than 2.5 cm.

[0109] Embodiment 52. The process of any previous enumerated Embodiment wherein the feed ore has a particle size less than 1.25 cm.

[0110] Embodiment 53. The process of any previous enumerated Embodiment wherein the feed ore has a particle size less than 1 cm.

[0111] Embodiment 54. The process of any previous enumerated Embodiment wherein the feed ore has a particle size less than 5000 pm.

[0112] Embodiment 55. The process of any previous enumerated Embodiment wherein the feed ore has a particle size less than 3350 pm.

[0113] Embodiment 56. The process of any previous enumerated Embodiment wherein the feed ore has a particle size less than 2820 pm.

[0114] Embodiment 57. The process of any previous enumerated Embodiment wherein the feed ore has a particle size less than 2380 pm.

[0115] Embodiment 58. The process of any previous enumerated Embodiment wherein the feed ore has a particle size less than 2000 pm.

[0116] Embodiment 59. The process of any previous enumerated Embodiment wherein the feed ore has a particle size less than 1680 pm.

[0117] Embodiment 60. The process of any previous enumerated Embodiment wherein the feed ore has a particle size less than 1410 pm.

[0118] Embodiment 61. The process of any previous enumerated Embodiment wherein the feed ore has a particle size less than 1000 pm.

[0119] Embodiment 62. The process of any previous enumerated Embodiment wherein the feed ore has a particle size of at least 105 pm.

[0120] Embodiment 63. The process of any previous enumerated Embodiment wherein the feed ore has a particle size of at least 125 pm.

[0121] Embodiment 64. The process of any previous enumerated Embodiment wherein the feed ore has a particle size of at least 149 pm.BANIQL 3013654.004

[0122] Embodiment 65. The process of any previous enumerated Embodiment wherein the reaction mixture is under a pressure of less than 2 standard atmospheres (<1520 mm Hg).

[0123] Embodiment 66. The process of any previous enumerated Embodiment wherein the reaction mixture is under a pressure of less than 1.5 standard atmospheres (<1140 mm Hg).

[0124] Embodiment 67. The process of any previous enumerated Embodiment wherein the reaction mixture is under a pressure of less than 1.25 standard atmospheres (<1140 mm Hg).

[0125] Embodiment 68. The process of any previous enumerated Embodiment wherein the reaction mixture is under a pressure of less than 1.25 standard atmospheres (<1140 mm Hg).

[0126] Embodiment 69. The process of any previous enumerated Embodiment wherein the reaction mixture is under a pressure that does not exceed standard atmospheric pressure (760 mm Hg).

[0127] Embodiment 70. The process of any previous enumerated Embodiment wherein the reaction mixture is at a temperature not in excess of 120 °C.

[0128] Embodiment 71. The process of any previous enumerated Embodiment wherein the reaction mixture is at a temperature not in excess of 110 °C.

[0129] Embodiment 72. The process of any previous enumerated Embodiment wherein the reaction mixture is at a temperature not in excess of 100 °C.

[0130] Embodiment 73. The process of any previous enumerated Embodiment wherein the reaction mixture is at a temperature not in excess of 95 °C.

[0131] Embodiment 74. The process of any previous enumerated Embodiment wherein the reaction mixture is at a temperature not in excess of 90 °C.

[0132] Embodiment 75. The process of any previous enumerated Embodiment wherein the feed ore further comprises a mineralized form of cobalt and the leachate comprises cobalt extracted from the phosphoric acid treated ore.BANIQL 3013654.004

[0133] Embodiment 76. The process of any previous enumerated Embodiment wherein the feed ore comprises a lateritic ore.

[0134] Embodiment 79. The process of any previous enumerated Embodiment wherein the feed ore comprises limonite ore.

[0135] Embodiment 80. The process of any previous enumerated Embodiment wherein the feed ore comprises saprolite ore.

[0136] Embodiment 81. The process of any previous enumerated Embodiment wherein the process further comprises electrowinning nickel from the separated leachate.

[0137] Embodiment 82. The process of any previous enumerated Embodiment wherein the process further comprises electrowinning cobalt from the separated leachate.

[0138] Embodiment 83. The process of any previous enumerated Embodiment wherein the phosphate is selected from the group consisting of phosphoric acid and phosphate salts.

[0139] Embodiment 84. The process of any previous enumerated Embodiment wherein the phosphate is a phosphate selected from the group consisting of mono, di and trisodium phosphate.

[0140] Embodiment 85. The process of any previous enumerated Embodiment wherein the phosphate is selected from the group consisting of dicalcium phosphate, tricalcium phosphate and hydroxapetite.

[0141] Embodiment 86. The process of any previous enumerated Embodiment wherein the phosphate is selected from the group consisting of mono, di and triammonium phosphates.

[0142] Embodiment 87. The process of any previous enumerated Embodiment wherein the phosphate is selected from the group consisting of ammonium calcium phosphate, di or trimagnesium phosphate, mixed anion phosphates, superphosphates, other phosphate-bearing compositions or minerals, and combinations thereof.BANIQL 3013654.004

[0143] Embodiment 88. The process of any previous enumerated Embodiment wherein the concentration of phosphate in the reaction mixture is within the range of 0.01 M to 1 M.

[0144] Embodiment 89. The process of any previous enumerated Embodiment wherein the concentration of phosphate in the reaction mixture is within the range of 0.05 M to 0.5 M.

[0145] Embodiment 90. The process of any previous enumerated Embodiment wherein the concentration of phosphate in the reaction mixture is within the range of 0.1 M to 0.35 M.

[0146] Embodiment 91. The process of any previous enumerated Embodiment wherein the molar ratio of the phosphate source to iron comprised by the feed ore in the reaction mixture is at least 1:50, respectively.

[0147] Embodiment 92. The process of any previous enumerated Embodiment wherein the molar ratio of the phosphate source to iron comprised by the feed ore in the reaction mixture is at least 1:40, respectively.

[0148] Embodiment 93. The process of any previous enumerated Embodiment wherein the molar ratio of the phosphate source to iron comprised by the feed ore in the reaction mixture is at least 1:30, respectively.

[0149] Embodiment 94. The process of any previous enumerated Embodiment wherein the molar ratio of the phosphate source to iron comprised by the feed ore in the reaction mixture is at least 1:20, respectively.

[0150] Embodiment 95. The process of any previous enumerated Embodiment wherein the molar ratio of the phosphate source to iron comprised by the feed ore in the reaction mixture is at least 1:10, respectively.

[0151] Embodiment 96. The process of any previous enumerated Embodiment wherein the molar ratio of the phosphate source to iron comprised by the feed ore in the reaction mixture is at least 1:7.5, respectively.

[0152] Embodiment 97. The process of any previous enumerated Embodiment wherein the molar ratio of the phosphate source to iron comprised by the feed ore in the reaction mixture is at least 1:5, respectively.BANIQL 3013654.004

[0153] Embodiment 98. The process of any previous enumerated Embodiment wherein the molar ratio of the phosphate source to iron comprised by the feed ore in the reaction mixture is at least 1:2, respectively.

[0154] Embodiment 99. The process of any previous enumerated Embodiment wherein the molar ratio of the phosphate source to iron comprised by the feed ore in the reaction mixture is at least 1:1, respectively.

[0155] Embodiment 100. The process of any enumerated Embodiments 1 - 96 wherein the molar ratio of the phosphate source to iron comprised by the feed ore in the reaction mixture is less than 1:5, respectively.

[0156] Embodiment 101. The process of any enumerated Embodiments 1 - 96 wherein the molar ratio of the phosphate source to iron comprised by the feed ore in the reaction mixture is less than 1:6, respectively.

[0157] Embodiment 102. The process of any enumerated Embodiments 1 - 96 wherein the molar ratio of the phosphate source to iron comprised by the feed ore in the reaction mixture is less than 1:7, respectively.

[0158] Embodiment 103. The process of any enumerated Embodiments 1 - 96 wherein the molar ratio of the phosphate source to iron comprised by the feed ore in the reaction mixture is less than 1:10, respectively.

[0159] Embodiment 104. The process of any previous enumerated Embodiment wherein the molar ratio of the phosphate source to the combined amount of iron and aluminum comprised by the feed ore in the reaction mixture is at least 1:50, respectively.

[0160] Embodiment 105. The process of any previous enumerated Embodiment wherein the molar ratio of the phosphate source to the combined amount of iron and aluminum comprised by the feed ore in the reaction mixture is at least 1:40, respectively.

[0161] Embodiment 106. The process of any previous enumerated Embodiment wherein the molar ratio of the phosphate source to the combined amount of iron and aluminum comprised by the feed ore in the reaction mixture is at least 1:30, respectively.BANIQL 3013654.004

[0162] Embodiment 107. The process of any previous enumerated Embodiment wherein the molar ratio of the phosphate source to the combined amount of iron and aluminum comprised by the feed ore in the reaction mixture is at least 1:20, respectively.

[0163] Embodiment 108. The process of any previous enumerated Embodiment wherein the molar ratio of the phosphate source to the combined amount of iron and aluminum comprised by the feed ore in the reaction mixture is at least 1:10, respectively.

[0164] Embodiment 109. The process of any previous enumerated Embodiment wherein the molar ratio of the phosphate source to the combined amount of iron and aluminum comprised by the feed ore in the reaction mixture is at least 1:7.5, respectively.

[0165] Embodiment 110. The process of any previous enumerated Embodiment wherein the molar ratio of the phosphate source to the combined amount of iron and aluminum comprised by the feed ore in the reaction mixture is at least 1:5, respectively.

[0166] Embodiment 111. The process of any previous enumerated Embodiment wherein the molar ratio of the phosphate source to the combined amount of iron and aluminum comprised by the feed ore in the reaction mixture is at least 1:2, respectively.

[0167] Embodiment 112. The process of any previous enumerated Embodiment wherein the molar ratio of the phosphate source to the combined amount of iron and aluminum comprised by the feed ore in the reaction mixture is at least 1:1, respectively.

[0168] Embodiment 113. The process of any enumerated Embodiments 1 - 96 wherein the molar ratio of the phosphate source to iron comprised by the feed ore in the reaction mixture is less than 1:5, respectively.

[0169] Embodiment 114. The process of any previous enumerated Embodiment wherein the molar ratio of the phosphate source to the combined amount of iron and aluminum comprised by the feed ore in the reaction mixture is less than 1:6, respectively.BANIQL 3013654.004

[0170] Embodiment 115. The process of any previous enumerated Embodiment wherein the molar ratio of the phosphate source to the combined amount of iron and aluminum comprised by the feed ore in the reaction mixture is less than 1:7, respectively.

[0171] Embodiment 116. The process of any previous enumerated Embodiment wherein the molar ratio of the phosphate source to the combined amount of iron and aluminum comprised by the feed ore in the reaction mixture is less than 1:10, respectively.

[0172] Embodiment 117. The process of any previous enumerated Embodiment wherein the reaction mixture comprises a source of ammonium and the concentration of the ammonium in the reaction mixture is within the range of 0.01 M to 1 M.

[0173] Embodiment 118. The process of any previous enumerated Embodiment wherein the reaction mixture comprises a source of ammonium and the concentration of the ammonium in the reaction mixture is within the range of 0.05 M to 0.75 M.

[0174] Embodiment 119. The process of any previous enumerated Embodiment wherein the reaction mixture comprises a source of ammonium and the concentration of the ammonium in the reaction mixture is within the range of 0.075 M to 0.5 M.

[0175] Embodiment 120. The process of any previous enumerated Embodiment wherein the reaction mixture is at a pH in the range of pH 1 to pH 4.5.

[0176] Embodiment 121. The process of any previous enumerated Embodiment wherein the reaction mixture is at a pH of at least 1.5.

[0177] Embodiment 122. The process of any previous enumerated Embodiment wherein the reaction mixture is at a pH of at least 1.8.

[0178] Embodiment 123. The process of any previous enumerated Embodiment wherein the reaction mixture is at a pH of at least 2.

[0179] Embodiment 124. The process of any previous enumerated Embodiment wherein the reaction mixture is at a pH of at least 2.2.BANIQL 3013654.004

[0180] Embodiment 125. The process of any previous enumerated Embodiment wherein the reaction mixture is at a pH of at least 2.4.

[0181] Embodiment 126. The process of any previous enumerated Embodiment wherein the reaction mixture is at a pH of at least 2.6.

[0182] Embodiment 127. The process of any previous enumerated Embodiment wherein the reaction mixture is at a pH of at least pH 2.8.

[0183] Embodiment 128. The process of any previous enumerated Embodiment wherein the reaction mixture is at a pH of at least 3.

[0184] Embodiment 129. The process of any previous enumerated Embodiment wherein the reaction mixture is at a pH of less than 4.

[0185] Embodiment 130. The process of any previous enumerated Embodiment wherein the reaction mixture is at a pH of less than 3.5.

[0186] Embodiment 131. The process of any previous enumerated Embodiment wherein the reaction mixture is at a pH of less than 3.BANIQL 3013654.004EXAMPLES

[0187] Lateritic ore (nickel bearing ore) was obtained from Sulawesi, Indonesia and Zambales, Philippines and sieve to a particle size between 500 pm to 2000 pm. Samples were taken and analyzed by inductive coupled plasma-mass spectrometry (ICP-MS) via acid digestion using aqua regia. Table A provides elemental composition by acid digestion via ICP-MS on each sample. Table B provides mineral composition of three different lateritic ores using X-ray Diffraction (XRD).

[0188] The samples are categorized into three types. Of the three types, Type A has the greatest amount of magnesium and lowest amount of iron, chromium and aluminum, Type B has a medium amount of magnesium, iron, chromium, and aluminum, and Type C has the least amount of magnesium and the greatest amount of iron, chromium, and aluminum.

[0189] In the Examples that follow and unless otherwise indicated, samples identified as Type A, Type B or Type C have the composition indicated in Tables A and B.Table AElement wt. % in Ore TypeOriginalOre Type country Ni Co Fe Mn Cr Al Ca Mg Na Type A Indonesia 1.46 0.03 11.69 0.21 0.21 0.85 0.93 14.54 0.02 Type B Indonesia 1.43 0.04 14.86 0.23 0.33 1.19 0.59 8.42 0.02 Type C Philippines 0.86 0.09 24.07 0.4 0.41 3.35 0.21 1.76 0.01Table BOre Type Mineral composition in Ore TypeLizardite, Clintonite-1 M, Cronstedtite-1 M, Mg2Si2Feoo? Alo is Sii 94 Os Ca (AI050 Feo is Mgo35) (Mg174 AI02s) (Si25 Type A Feasas Sii.461 Os (OH)4 (OH)4 AI27S) O10) (OH)2Kaolinite- 1 A, Iron Oxide Hydroxide,Type B Al2(Si2Os)(OH)4 FeO(OH)Aluminum iron iron(lll) silicon oxideType C hematite, syn, Fe2Oa oxide, Al Fe2O4 SiO2BANIQL 3013654.004EXAMPLE 1

[0190] One hundred (100) grams of ore Types A, B and C were combined with a leachant having the indicated composition in each of the following runs.

[0191] Type A ore series: The leachant for the first series, LA1, LA2, and LA3 contained 400 grams of water, premixed with 30 or 40 or 50 grams of Sulfuric acid (H2SO4, 93 wt%), which translates to 0.66M, 0.86M, and 1.05M, respectively. The leachant for the second series, LA4, LA5, and l_A6 contained 400 grams of water, premixed with 30 or 40 or 50 grams of sulfuric acid (H2SO4, 93 wt%), which translates to 0.66M, 0.86M, and 1.05M, respectively, and 5 grams of phosphoric acid (H3PO4, 85 wt%), which translates to 0.11 M. The leachant for the third series, LA7, LA8, and LA9, contained 400 grams of water, premixed with 30 or 40 or 50 grams of sulfuric acid (H2SO4, 93 wt%), which translates to 0.66M, 0.86M, and 1.05M, respectively, and 10 grams of phosphoric acid (H3PO4, 85%), which translates to 0.23M. In each run of each series, the sulfuric and phosphoric acid solution were premixed for 15 minutes, and 100 grams of ore were added into the solution. The mixture was maintained at 80 - 85°C and mixed at 230 rpm for four hours. After four hours of mixing, the solution was filtered from the solid sludge, the pH was measured, and 2 mL of the leachate was tested for elemental composition via ICP-MS.

[0192] Type B ore series: The procedure of the Type A series was replicated, except that Type B ore was substituted for Type A ore in series LB1 -LB9, respectively.

[0193] Type C ore series: The procedure of the Type A series was replicated, except that Type C ore was substituted for Type A ore in series LC1 -LC9, respectively.

[0194] The results are presented in Table 1 for each of the series.BANIQL 3013654.004Table 1Leachate extraction efficiency after 4h Leaching(%) RatioN i / (Fe+Al) (mol / mol) PO₄ / Fefmol / mol) Ni / Fe (g / g)Sample Ore Type H2SO4H3PO4pH final Ni Fe Al Mg Co Cr Mn IntheIn the Ore In the Solutionsolution IllllSpssigjs iiiiilliiiii iiiiililliiii iiiiiii iiililiii iliili iiiiiiiiiii iiiiilii iiiiilii iiiiilii iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii iiiiiiiiiiiliiiiiiiiii iiiiiiiiiiiiiiiiiiliiiiiiiiiiiiiiiii LA240 2.23 68.96 14.44 23.96 44.41 58.95 26.31 59.51 0 0.597 0.452 (comparative)iiiiiiiiiiilliiiiiiiiiii iiiiiiiiiii iiiiiliiliiiii iiiiiiiiiii iiiHii iiifii iiililiii iiiiilii iiiiilii iiiiiiiii iiiiiiiiiiiiiiiiiliiiiiiiiiiiiiiiii iiiiiiiiiilllliiiiiiiiii iiiiiiiiiiiiiiiiililliiiiiiiiiiiiiiiii LA4 30 5 2.92 58.39 0.20 0.38 42.11 34.21 0.62 36.02 0.24 37.394 27.323iiiiiiiiiii iiiiiiliiiiii iiiiilliiiii) iiilliiii iiiiiliii iiiii iiiiilii iiiiii iiiiiii iiiiiii iiiiiiiiiiiiiiiiiiiiiiiiiiiiiii iiiiiiiiiiiiliiiiiiiiii iiiiiiiiiiiiiiiilllliiiiiiiiiiiiiii LA6 50 5 1.99 74.97 8.99 29.62 71.51 50.43 26.95 53.28 0.24 1.041 0.659 iiiiiiiiiiiiiiiiiiiiiiiii iiiiiiiiiii iiiiiiiiiii iiiiilliiiii iiiiiiiiiii iiiMii iiiiilii iiiiiii iiiiii iiiiilii iiiiilii iiiiiiiiiiiiiiiiiiiiiiiiiiiiiii iiiiiiiiiiiiliiiiiiiiii iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii LA8 40 10 2.78 85.43 1.06 1.58 77.44 49.63 0.18 50.64 0.49 10.022 7.761 iiililiisi iiiiiiiiiii iiiiiiliiiiii iiiiilliiiii iiiiiiliiiiii iiiiiiliii iiHiii iiiiilii iiiiilii iiiiilii iiiiilii iiiiiiiiiiiiiiiiiiiiiiiiiiiiiii iiiiiiiiiiliiOiiiiiiiiii iiiiiiiiiiiiiiilOiiiiiiiiiiiiiii LB130 2.16 74.34 7.89 26.18 49.47 47.24 22.64 29.11 0.00 0.907 0.255 (comparative)iiiiiiiiiiillliiiiiiiiiii iiiiilliiiii iiiiilliiiii iiiiiii iiiilii iiiii iiiii iiiiii iilllii iiiiilii iiiiiiiiiiiiiiiiiliiiiiiiiiiiiii iiiiiiiiiiiiliiiiiiiiii iiiiiiiiiiiiiiiilliiliiiiiiiiiiiiiiii LB350 1.69 87.23 20.55 45.62 75.92 61.89 39.22 38.77 0.00 0.415 0.285 (comparative)iiiiilliiiii iiiiil iiiiiliiliiii iiiiiiiiiii iiiiilii iillli iiiiil iliiii iiiiiii iiiiiiiii iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii iiiiiiiiiiiiiiiiiiiii iiiiiiiiiiiiiiiiiiiifiiiiiiiiiii^iiiii Type BLB5 40 5 1.79 89.28 10.16 44.16 78.38 63.69 34.21 39.17 0.19 0.845 0.465iBiiiiii iiiiiiliiiiii iiiiilliiiii iiiiiiiii iiiiilii iiiii iiiiiliiii iiiilii iliiii iiiiilii iiiiiiiiiiiiiiOiiiiiiiiiiiiii iiiiiiiiiiiiliiiiiiiiii iiiiiiiiiiiiiiiiiliiiiiiiiiiiiiiiiiiii LB7 30 10 2.38 89.87 1.22 17.24 63.18 54.32 7.19 32.87 0.38 7.117 2.011 iiiiiiiiiiiiiiiiiiiiii iiiiilliiiii iiiiiiliiiiii iiiiiiliiiiii iiililii iiiiiiii iitiii iiiii iiiiiii iiiiiiii iiiiiiiiiiiiiiiiiiiiiiiiiiiiii iiiiiiiiiiiiliiiiiiiiii iiiiiiiiiiiiiiiiiiilliiiiiiiiiiiiiiii) LB9 50 10 1.35 95.23 26.00 41.25 56.84 63.10 46.29 35.58 0.38 0.352 0.264 iiiiiiiiiiiloiiiiiiiiii iiiiiiiiiii iiiiliiiiiiii iiiliiiiii) iiiiiiiii iiiiilii iiiiiiiii iiiiilii iiliili ismi iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii iiiiiiiiiiliOiiiiiiiii iiiiiiiiiiiiiiiiiililiiiiiiiiiiiiiii LC2 ggt^ribgs40 1.46 53.20 32.60 57.15 85.64 32.30 34.67 39.75 0.00 0.058 0.037(comparative)BANIQL 3013654.004iiiil iiiiiii iiili iBiiiLC4 30 5 1.45 53.39 21.91 55.99 81.12 27.77 28.14 32.81 0.12 0.087 0.047 iiolLC6 50 5 1.25 69.24 37.77 67.96 99.26 32.44 40.26 38.80 0.12 0.066 0.041 illlililllLC8 40 10 0.92 67.73 32.11 69.26 86.65 33.26 40.03 39.33 0.24 0.075 0.044|:||||||||||||iiiiBiiiii liiil liilili iilii BBiii iiltii iiiiii^iiiBANIQL 3013654.004EXAMPLE 2

[0195] Leachates obtained in Example 1 were initially heated to 60 °C and the temperature was thereafter maintained in the 55°C - 65°C range. Limestone(99% CaCO3) was added into the stirred solution until the pH achieved a value in the 4.5 to 5.5 range, and the solution was then stirred for another 30 minutes before filtration. After being filtered, the sample from each solution was taken to determine the elemental composition and concentration. The amount of limestone added, the initial pH (prior to limestone addition), the final pH (post limestone addition), the extraction efficiency (the percentage of each element contained by the ore that is extracted into the neutralized leachate) and results are presented in Table 2.Table 2Extraction efficiency of each metal in neutralized leachate relative to ore (%)Sam Ore PH PHpie Type H2SO4H3PO4CaCO3initial final Ni Fe Al Mg Co Cr Mn §igil ii®i liiiiii iMii ilii§i iiiili lOOl i§iili§ LA2 40 5.25 2.23 5.05 64.24 0.09 0.29 35.2 50.28 1.1 54.52Iglil iiii^ii 11111 1S161 11I131§ 11611 lllll iillii§ lllll§ ■ii lllll LA4 30 5 6.3 2.92 4.88 64.13 0.09 0.03 41.47 38.24 012 39.61 §11111 ligl iiiii iiiii? iiiiiii 1§|||§| ffOli LA6 50 5 4.69 1.99 5.35 50.74 0.57 0.03 58.31 40.12 013 45.97 §IHH iglii iitiii lOll liiii 11I161§ iini inn ISHli l§6i6§i LA8 40 10 2.25 2.78 4.56 66.22 0.01 0.04 59.47 37.39 014 37.63 §11111 llliili SMii ll§li iMiit iiiii§LB1 30 5.56 2.24 4.7 47.84 0.19 1.5 44.22 31.96 035 21.69 1M1 1101 ■ii 11611 lilii iiiiiii 11111 l§ii6i§ llilll; lllll LB3 50 12.94 1.69 4.61 46.28 0.15 1.37 46.72 35.43 028 24.85 fsoi itoii I§IIBII 2.13 iiiii 1116§1§ lllii iiiiii Olli LB5 TypeB 40 5 751 1 79 474 6506 001 002 592 4422 006 274 tog liiiiii lOii liliii Hill iMii 1011 IMll 11M11 i§iOi§ LB7 30 10 3.89 2.38 4.7 85.53 0.01 0.18 48.41 50.78 067 26.3 Igll iilli§i iillii lllll lisiiii iiii§iLB9 50 10 15.01 1.35 4.9 83.46 0.01 0.18 46.31 51.45 064 25.06HO11 iilll 1§1661§ iiili§ IMI llti LC2 40 20.74 1.46 5.28 1.71 0.00 0.01 38.82 4.07 007 13.08. iyis.Mill liii■io liilii lllll iMii illill i liilliLC4 30 5 14.97 1.45 5.31 7.16 0.01 0.07 54.92 6.91 061 13.34 iiiiii ilili liliiii liiiiii liOi ssti IMIIBANIQL 3013654.004LC6 50 5 30.39 1.25 4.98 11.45 0.01 0.09 47.20 7.25 073 11.59 iiwii 1WB 1001 MB® LC8 40 10 24.95 0.92 5.46 0.52 0.01 0.07 40.42 2.67 059 3.03tiOil IMliExample 3:

[0196] In this series, one hundred (100) grams of limonitic (Lim), transition (Tm), or saprolitic (Sap) ores having a particle size in the range of 500 - 2,000 micrometers and the composition indicated in Table 3, obtained from Sulawesi, Indonesia were evaluated.

[0197] In each experiment (with a replicate for each), 400 grams of water were premixed with 30 grams of Sulfuric acid (H2SO4, 93 wt%), 0.66M and 5 grams of phosphoric acid (H3PO4, 85%), 0.11 M. The sulfuric and phosphoric acid solution was premixed for 15 minutes, and 100 grams of ore were added into the solution.The mixture was maintained at 80 to 85 °C and mixed at 230 rpm for four hours.After four hours of mixing, the solution was filtered from the solid sludge, and the pH was measured. Lastly, 2 mL of sample was taken to test the elemental composition via ICP-MS.

[0198] The composition of the ore (wt%), ore type, pH of the leachate after 4 hours, the mole ratio of phosphate in the leachant to iron in the ore sample, the extraction efficiency for each metal in the leachate relative to the ore, and the weight ratio of nickel to iron in the leachate are presented in Table 3.Table 3ID Ore Content Ore type pH (4h) PO4 / Fe Leachate extraction Ni / Fe (mol / mol) efficiency after 4h Leaching (g / g)(%)Ni % Fe % Al % Mg % Ni Fe Al Lim_01 1.40 4556 2.99 1.10 Lim 0.75 0.053 1308% 6.10% 28.12% 0.066 Lim_01 1.40 4556 2.99 1.10 Lim 0.6 0.053 1321% 6.56% 28.66% 0.062 Lim_02 1.03 4210 3.92 0.44 Lim 0.6 0.058 11 43% 7.70% 38.24% 0.036 Lim_02 1.03 4210 3.92 0.44 Lim 0.51 0.058 2628% 13.54% 73.81 % 0.048 Lim_03 1 15 41 89 369 1 08 Lim 078 0058 1206% 600% 21 25% 0055 Lim_03 1.15 41 89 3.69 1.08 Lim 0.49 0.058 1290% 6.77% 22.25% 0.052 Lim_04 1.20 4389 3.23 <0.01 Lim 0.99 0.055 1010% 8.71 % 38.40% 0.032 Lim_04 1.20 4389 3.23 <0.01 Lim < 001 0.055 9.26% 8.26% 31.91 % 0.031 Lim_05 1.12 4067 2.60 0.73 Lim 0.15 0.06 11 50% 7.50% 21.18% 0.042BANIQL 3013654.004Lim_05 1.12 4067 2.60 0.73 Lim 0.03 0.06 1368% 8.60% 28.13% 0.044 Lim_06 1.17 4628 3.02 0.91 Lim 0.75 0.052 1234% 11.03% 41.27% 0.028 Lim_06 1.17 4628 3.02 0.91 Lim 0.29 0.052 8.14% 7.94% 34.81 % 0.026 Lim_07 1.22 41 15 317 1 14 Lim 024 0059 677% 205% 1229% 0098 Lim_07 1.22 41 15 3.17 1.14 Lim 0.03 0.059 1649% 6.41 % 29.37% 0.076 Lim_08 1.15 4599 3.91 <0.01 Lim 0.77 0.053 9.16% 8.37% 39.13% 0.027 Lim_08 1.15 4599 3.91 <0.01 Lim 0.41 0.053 8.72% 8.26% 39.44% 0.026 Lim_09 1.22 4493 3.92 <0.01 Lim 0.61 0.054 7.74% 10.73% 48.00% 0.020 Lim_09 1.22 4493 3.92 <0.01 Lim 0.45 0.054 4.74% 7.68% 35.51 % 0.017 Lim_10 1.32 4907 3.14 <0.01 Lim 0.4 0.049 7.47% 6.48% 21.31 % 0.031 Lim_10 1.32 4907 3.14 <0.01 Lim 0.29 0.049 11 97% 9.89% 29.98% 0.032 Trn_01 1.40 34.01 3.07 1.99 Trn 0.4 0.071 2549% 5.70% 28.34% 0.184 Trn_01 1.40 34.01 3.07 1.99 Trn 0.38 0.071 2081% 4.71 % 23.80% 0.182 Trn_02 1.66 35.11 1.96 2.34 Trn 0.53 0.069 5381% 11.95% 45.09% 0.213 Trn_02 1.66 35.11 1.96 2.34 Trn 0.44 0.069 4992% 11.00% 40.59% 0.214 Trn_03 1.56 33.63 1.92 2.38 Trn 0.42 0.072 2833% 5.53% 29.78% 0.237 Trn_03 1 56 3363 1 92 238 Trn 034 0072 2008% 407% 21 41 % 0229 T rn_04 1.22 39.56 0.70 1.22 Trn 0.04 0.061 2731% 8.11% 40.41 % 0.104 Trn_04 1.22 39.56 0.70 1.22 Trn < 001 0.061 21 11% 6.62% 32.67% 0.098 Trn_05 1.25 39.37 3.08 0.98 Trn < 001 0.062 1624% 7.32% 26.34% 0.070 Trn_05 1.25 39.37 3.08 0.98 Trn < 001 0.062 1658% 6.34% 25.97% 0.083 Sap_01 1.47 29.47 2.17 3.35 Sap 0.87 0.082 3027% 4.99% 24.72% 0.303 Sap_01 1.47 29.47 2.17 3.35 Sap 0.94 0.082 4624% 7.55% 30.01 % 0.306 Sap_02 1.80 22.90 1.08 7.21 Sap 1.67 0.106 3995% 1.93% 17.40% 1.635 Sap_02 1.80 22.90 1.08 7.21 Sap 1.69 0.106 5934% 2.66% 20.92% 1.760 Sap_03 1.76 25.97 0.97 5.70 Sap 1.51 0.093 4465% 4.01 % 19.24% 0.752 Sap_03 1.76 25.97 0.97 5.70 Sap 1.49 0.093 3843% 1.45% 15.31% 1.787 Sap_04 1.77 23.51 0.81 6.40 Sap 1.55 0.103 4057% 2.54% 15.33% 1.200 Sap_04 1.77 23.51 0.81 6.40 Sap 1.45 0.103 4441% 3.09% 21.08% 1.081 Sap_05 1 49 2287 092 727 Sap 1 97 0106 5667% 446% 1883% 0825 Sap_05 1.49 22.87 0.92 7.27 Sap 2.05 0.106 7317% 1.19% 17.47% 4.006 Sap_06 1.68 29.27 1.46 4.20 Sap 0.86 0.083 3854% 6.22% 30.63% 0.355 Sap_06 1.68 29.27 1.46 4.20 Sap 0.96 0.083 3520% 0.46% 7.13% 4.395 Sap_07 1.65 35.24 1.85 2.61 Sap 1.35 0.069 2756% 5.13% 27.80% 0.252 Sap_07 1.65 35.24 1.85 2.61 Sap 1.16 0.069 3390% 6.81 % 36.97% 0.234 Sap_08 2.08 34.07 1.31 3.18 Sap 0.97 0.071 2933% 5.25% 29.00% 0.341 Sap_08 2.08 34.07 1.31 3.18 Sap 0.94 0.071 2948% 5.10% 29.05% 0.353Example 4

[0199] Four hundred (400) grams of water were premixed with 50 grams of sulfuric acid (H2SO4, 93 wt%), which translates to 1.05M, and combined with 100 grams of Type A ore (as characterized in Tables A and B). The mixture was maintained at a temperature in the 80 - 85 °C range and stirred at 230 rpm for fourBANIQL 3013654.004hours. After four hours, the solution was filtered from the solid sludge and the pH was measured. Lastly, 2 mL of the leachate sample was tested via ICP-MS to determine the concentration and amount of each element in the leachate.

[0200] To explore stoichiometry effect between iron and phosphate, the leaching was carried out in two steps: (i) an initial step in which the leachant comprised sulfuric acid but no phosphoric acid to yield an intermediate leachate, and (ii) a second step in which different amounts of phosphoric acid (85%) were added to the intermediate leachate, based on the amount of iron in the intermediate leachate: (a) 50 mole% (mole% of phosphate added to intermediate leachate relative to moles of iron in the intermediate leachate), 100% (mole% of phosphate added to intermediate leachate relative to moles of iron in the intermediate leachate), and 200% (mole% of phosphate added to the intermediate leachate relative to moles of iron in the intermediate leachate). Under the assumption that phosphate anion will only react with iron cation. The reaction chemistry follows this equation:3Fe + 2H3PO4Fe3(PO4)2 + 3H2

[0201] After the addition of the phosphoric acid to the intermediate leachate, the mixture solution was mixed at 80 °C for 2 hours. After that, the solution was filtered and the pH was measured and the samples were taken for ICP-MS to determine the amounts of remaining elements in the solution and the amount of each element precipitates from the reaction.

[0202] The ore type, pH of the leachate after 2 hours, mole ratio of phosphate in the leachant to iron in the ore sample, extraction efficiency for each metal in the leachate relative to the ore, and the weight ratio of nickel to iron in the leachate are presented in Table 5.Example 5

[0203] The procedure of Example 4 was repeated, except that Type B ore (as characterized in Tables A and B) was substituted for Type A ore. The ore type, pH of the leachate after 2 hours, mole ratio of phosphate in the leachant to iron in the ore sample, extraction efficiency for each metal in the leachate relative to the ore, and the weight ratio of nickel to iron in the leachate are presented in Table 5.BANIQL 3013654.004Table 5% metal in leachate relative tometal content in the oreH₃PO₄ / Fe PO₄ / Fe Ni / Fe (g / g) Ore Type Sample mol% (mol / mol) pH Ni Fe Al Mg Co Cr Mn In leachate LA3_BS 50% 0.04 1.66 79.10 21.76 32.83 58.43 69.58 34.49 71.22 3.64 Type A LA3_S 100% 0.09 1.45 62.58 9.52 24.93 45.21 53.85 22.68 54.11 6.57 LA3_AS 200% 0.17 1.30 63.50 0.89 12.24 46.86 55.15 15.79 56.56 71.40 LB3_BS 50% 0.04 1.23 88.33 28.13 53.85 73.68 63.88 49.77 38.32 3.14 Type B LB3_S 100% 0.09 1.14 87.56 28.41 52.84 71.82 63.26 48.91 38.42 3.08LB3_AS 200% 0.17 0.99 87.53 28.52 52.56 72.04 61.94 48.84 38.11 3.07Example 6

[0204] The leachates obtained in Example 5 were heated to 65°C and stirred with a magnetic stir bar. While stirring, NaOH solution (1 M) was slowly dripped into the leachant until the pH reached a value of 2 or 3 (as indicated in Table 6). Once the pH reached the target pH, the solution was stirred for an additional 30 minutes. Finally, the solution was filtered from any solid sludge, and the sample was evaluated to determine the extraction efficiency and the leachate composition.

[0205] The ore type, pH of the leachate after 2 hours, mole ratio of phosphate in the leachant to iron in the ore sample, extraction efficiency for each metal in the leachate relative to the ore, and the weight ratio of nickel to iron in the leachate are presented in Table 6.BANIQL 3013654.004Table 6% in leachate after NaOH addition relative to metal content in the ore Ratio Ni / Fe Ore H₃PO₄ / Fe (g / g) Type Sample mol% pH Ni Fe Al Mg Co Cr Mn leachate LA3_BS 50% 59.30 2.55 42.44 40.05 50.70 16.23 49.78 23.25 Type 2.LA3_S 100% 66.85 5.68 24.73 47.93 56.65 22.65 59.20 11.77 A 0LA3_AS 200% 45.49 1.61 23.50 31.15 37.56 10.66 36.62 28.18 LA3_BS 50% 62.34 2.20 23.34 43.14 52.64 15.79 53.85 28.32 Type 3.LA3_S 100% 65.82 0.45 16.65 35.17 55.49 13.19 54.26 147.20 A 0LA3_AS 200% 32.28 0.03 24.83 21.92 27.00 5.70 26.01 1123.02 LB3_BS 50% 76.39 11.82 42.16 63.60 54.76 35.35 34.23 6.46 Type 2.LB3_S 100% 82.18 4.05 36.62 59.42 37.10 29.79 34.37 20.27 B 0LB3_AS 200% 58.42 4.24 4.92 0.04 41.81 16.48 30.19 13.77 LB3_BS 50% 86.68 1.84 43.30 72.34 62.93 26.70 38.46 47.17 Type 3.LB3_S 100% 76.90 0.17 16.64 54.81 53.40 17.29 31.49 453.93 B 0LB3_AS 200% 63.65 0.07 7.43 54.04 45.03 6.36 27.39 943.58Example 8

[0206] One hundred (100) grams of ore Types A, B and C (as described in Tables A and B) were combined with a leachant having the indicated composition in each of the following runs.

[0207] Type A ore series: The leachant for the first series, LA1, LA2, and LA3 contained 400 grams of water, premixed with 30 or 40 or 50 grams of Sulfuric acid (H2SO4, 93 wt%), which translates to 0.66M, 0.86M, and 1.05M, respectively. The leachant for the second series, LA10, LA11, and LA12 contained 400 grams of water, premixed with 30 or 40 or 50 grams of sulfuric acid (H2SO4, 93 wt%), which translates to 0.66M, 0.86M, and 1.05M, respectively, and 5 grams of monoammonium phosphate (MAP), which translates to 0.11 M. The leachant for the third series, LA13, LA14, and LA15, contained 400 grams of water, premixed with 30 or 40 or 50 grams of sulfuric acid (H2SO4, 93 wt%), which translates to 0.66M, 0.86M, and 1.05M, respectively, and 10 grams of MAP, which translates to 0.22M. In each run of each series, the sulfuric and phosphoric acid solution were premixed for 15 minutes, and 100 grams of ore were added into the solution. The mixture was maintained at 80 - 85°C and mixed at 230 rpm for four hours. After four hours ofBANIQL 3013654.004mixing, the solution was filtered from the solid sludge, the pH was measured, and 2 mL of the leachate was tested for elemental composition via ICP-MS.

[0208] Type B ore series: The procedure for the Type A series was repeated except that Type B ore was substituted for Type A ore in LB1, LB2, LB3, and LB10-LB15.

[0209] Type C ore series: The procedure for the Type A series was repeated except that Type C ore was substituted for Type A ore in LC1, LC2, LC3, and LC10-LC15.

[0210] The ore type, pH of the leachate after 4 hours, amount of MAP included in the leachant, mole ratio of phosphate in the leachant to iron in the ore sample, extraction efficiency for each metal in the leachate relative to the ore, the weight ratio of nickel to iron in the leachate, and mole ratio of nickel to iron + aluminum (mol / mol) in the leachate are presented in Table 8.BANIQL 3013654.004Table 8Leachate extraction efficiency after 4h Leaching (%)PO4 / Fe Ni / (Fe+Al) Sample Ore MAP pH final Ni Fe Al Co Cr Mn (mol / mol) Ni / Fe (g / g)Type Mg(g) i in leachate (mol / mol) n Ore in leachate LA1(comparative 30 2.35 63.96 5.85 1877 39.67 49.52 18.60 48.53 0.00 0.912 1.002 )LA2(comparative 40 2.23 68.96 14.44 2396 44.41 58.95 26.31 59.51 0.00 0.597 0.452 )LA3(comparative 50 2. W 72.85 18.98 2572 50.37 62.81 28.88 63.80 0.00 0.428 0.340 ) TypeA LA10 30 5 48.02 0.34 1041 37.99 23.74 1.64 24.89 0.24 3.23 17.513 2.975 LA11 40 5 2.76 69.55 2.12 9.95 48.27 50.30 11.90 49.56 0.24 4.107 2.277 LA12 50 5 2.43 94.63 9.98 29.90 71.60 73.50 29.99 74.05 0.24 1.184 0.773 LA13 30 10 4.28 49.32 0.02 3.57 37.49 14.14 1.36 15.07 0.49 252.644 10.384 LA14 40 10 3.71 67.96 0.05 3.86 51.39 33.13 1.33 35.45 158.831 12.685 LA15 50 10 2.65 79.56 0.79 13.03 58.92 43.67 3.86 44.94 0.49 12.561 3.420 LB1(comparative 30 2.16 74.34 7.89 2618 49.47 47.24 22.64 29.11 0.00 0.907 0.255 )LB2(comparative 40 1.90 77.95 17.26 3749 66.49 55.51 34.46 35.21 0.00 0.435 0.303 )LB3(comparative 50 1.69 87.23 20.55 4562 75.92 61.89 39.22 38.77 0.00 0.415 0.285 Type) BLB10 30 5 2.53 61.44 0.74 28.19 46.55 37.89 8.82 24.51 0.19 8.00 1.04 LB11 40 5 2.00 89.77 10.71 4998 67.33 61.61 31.74 37.79 0.19 0.806 0.431 LB12 50 5 1.58 86.87 15.28 54.13 65.32 60.64 42.05 37.58 0.19 0.55 0.327 LB13 30 10 2.08 63.50 1.34 19.31 51.23 36.75 2.28 21.04 0.38 4.550 1.273 LB14 40 10 70.97 5.90 39.66 57.53 45.74 18.32 28.09 0.38 1.44 1.150 0.518BANIQL 3013654.004LB15 50 10 1.12 80.89 2.11 3429 65.31 50.59 33.21 31.23 0.38 3.690 0.946 LC1(comparative 30 1.39 3989 1840 4470 7626 2452 21 70 3027 000 0077 0043 )LC2(comparative 40 1.46 53.20 32.60 5715 85.64 32.30 34.67 39.75 0.00 0.058 0.037 )LC3(comparative 50 1.21 58.84 40.39 6058 88.32 29.98 39.63 38.39 0.00 0.052 0.034 ) TypeLC10 C 30 5 1.23 56.55 13.50 5211 100.53 28.98 20.23 34.40 0.12 0.150 0.067 LC11 40 5 1.18 50.30 14.19 4796 97.10 27.91 20.78 32.62 0.12 0.127 0.061 LC12 50 5 1.13 63.60 24.88 5564 103.26 35.36 28.16 39.48 0.12 0.091 0.067 LC13 30 10 1.37 35.73 13.05 3779 75.49 21.26 16.70 27.03 0.24 0.098 0.051 LC14 40 10 1.24 75.60* 52.84 5207 133.7* 99 30.94 126.27 0.24 0.051 0.038LC15 50 10 1.26 50.03 25.80 4954 90.13 27.82 27.89 34.25 0.24 0.069 0.042 *The high number is due to calibration error resulting from low magnesium / elemental content in the ore, which caused error in the measurement.BANIQL 3013654.004Example 9:Neutralization from MAP from example 8.

[0211] The leachates obtained in Example 8 were heated to 60°C and the temperature was maintained between 55°C - 65°C. Limestone (99% CaCO3) was added into the solution while stirred until pH was above 4.5. Once the pH reached a value of 4.5 - 5.5, the solution was stirred for another 30 minutes before being filtered. After being filtered, the sample from each solution was taken to determine the elemental composition and concentration. The amount of CaCO3added relative to ore amount (%w / w), initial pH and final pH along with the overall extraction efficiency is presented in Table 9.BANIQL 3013654.004Table 9Overall extraction efficiency of each metal in neutral solution relative to the original ore (%) MAPSample Ore Type H2SO4(g) CaCO3pH initial pH final Ni Fe Al Mg Co Cr Mn LAI2.93 2.35 5.34 48.31 0.04 0.08 33.51 37.68 0.14 39.47 (comparative) 30LA25.25 2.23 5.05 64.24 0.09 0.29 35.2 50.28 1.1 54.52 (comparative) 40LAS7.83 2.12 4.86 37.93 0.02 0.06 29.87 32.5 0.09 36.9 (comparative) 50LA10 30 5 0.15 3.23 5.72 63.96 0.02 5.40 44.64 34.68 0.97 33.95Type ALA11 40 5 1.53 2.20 4.87 68.30 0.21 0.45 47.39 48.05 1.38 48.34 LA12 50 5 3.75 1.93 4.96 63.97 0.53 0.34 49.54 49.02 1.38 50.43 LA13 30 10 0.43 4.21 4.77 47.76 0.34 6.81 35.04 14.59 1.30 15.78 LA14 40 10 1.22 3.10 4.75 60.02 0.54 6.83 44.83 29.84 1.16 31.83 LA15 50 10 3.28 2.14 4.77 70.54 0.30 7.70 51.62 39.35 1.30 40.39 LB15.56 2.24 4.7 47.84 0.19 1.5 44.22 31.96 0.35 21.69 (comparative) 30LB28.28 2.02 4.83 30.61 0.18 1.65 41.32 25.35 0.3 21.92 (comparative) 40LB312.94 1.69 4.61 46.28 0.15 1.37 46.72 35.43 0.28 24.85 (comparative) 50LB10 30 5 2.31 2.17 5.10 61.44 0.57 2.13 47.22 37.08 0.52 22.50Type BLB11 40 5 6.81 1.66 4.61 65.22 0.02 5.28 57.50 41.83 0.71 25.18 LB12 50 5 11.75 1.36 5.06 63.87 0.01 4.10 51.49 43.00 0.65 25.59 LB13 30 10 1.30 2.08 4.92 63.50 0.41 3.65 44.51 34.35 0.60 17.63 LB14 40 10 5.24 1.86 5.21 54.57 0.25 3.11 44.77 33.95 0.58 20.01 LB15 50 10 9.26 1.48 5.01 69.35 0.36 5.11 54.69 45.50 0.67 27.93 LC1(comparative) 30 13.97 1.39 4.88 12.19 0.00 0.04 43.35 8.99 0.07 15.85Type CLC2(comparative) 40 20.74 1.46 5.28 1.71 0.00 0.01 38.82 4.07 0.07 13.08BANIQL 3013654.004LC3(comparative) 50 30.02 1.21 5.14 1.84 0.00 0.01 49.82 3.25 0.07 13.70 LC10 30 5 11.31 1.23 5.20 42.90 0.01 1.11 82.08 22.42 0.41 27.56 LC11 40 5 15.80 1.18 4.19 37.92 0.01 1.21 75.78 21.01 0.35 25.97 LC12 50 5 19.43 1.13 4.00 41.63 0.02 1.51 84.20 24.69 0.33 30.39 LC13 30 10 14.01 1.37 5.01 29.43 0.01 0.99 64.10 17.24 0.47 24.43 LC14 40 10 20.05 1.24 5.42 23.36 0.01 0.65 51.83 14.13 0.38 20.58LC15 50 10 24.02 1.26 5.27 25.12 0.01 1.38 64.60 15.32 0.61 24.46BANIQL 3013654.004Example 10

[0212] One hundred (100) grams of ore Types A, B and C (as described in Tables A and B) were combined with a leachant having the indicated composition in each of the following runs.

[0213] Type A ore series: The leachant for the first series, LA1, LA2, and LA3 contained 400 grams of water, premixed with 30 or 40 or 50 grams of Sulfuric acid (H2SO4, 93 wt%), which translates to 0.66M, 0.86M, and 1.05M, respectively. The leachant for the second series, LA16, LA17, and LA18 contained 400 grams of water, premixed with 30 or 40 or 50 grams of sulfuric acid (H2SO4, 93 wt%), which translates to 0.66M, 0.86M, and 1.05M, respectively, and 5 grams of di-ammonium phosphate (DAP), which translates to 0.095 M. The leachant for the third series, LA19, LA20, and LA21, contained 400 grams of water, premixed with 30 or 40 or 50 grams of sulfuric acid (H2SO4, 93 wt%), which translates to 0.66M, 0.86M, and 1.05M, respectively, and 10 grams of DAP, which translates to 0.19M. In each run of each series, the sulfuric and phosphoric acid solution were premixed for 15 minutes, and 100 grams of ore were added into the solution. The mixture was maintained at 80 - 85oC and mixed at 230 rpm for four hours. After four hours of mixing, the solution was filtered from the solid sludge, the pH was measured, and 2 mL of the leachate was tested for elemental composition via ICP-MS.

[0214] Type B ore series: The procedure for the Type A series was repeated except that Type B ore was substituted for Type A ore in LB1, LB2, LB3, and LB16-LB21.

[0215] Type C ore series: The procedure for the Type A series was repeated except that Type C ore was substituted for Type A ore in LC1, LC2, LC3, and LC16-LC21.

[0216] The ore type, pH of the leachate after 4 hours, amount of MAP included in the leachant, mole ratio of phosphate in the leachant to iron in the ore sample, extraction efficiency for each metal in the leachate relative to the ore, the weight ratio of nickel to iron in the leachate, and mole ratio of nickel to iron + aluminum (mol / mol) in the leachate are presented in Table 10.BANIQL 3013654.004Table 10Leachate extraction efficiency after 4h Leaching (%) RatioPO₄ / FeNi / Fe (g / g) Ni / (Fe+Al) (mol / mol) Sample „ _ DAP (g)Ore Type H2SO4.. pH final Ni Fe Al Mg Co Cr Mn (mol / mol)(g) in leachate in leachate in oreLAI 30 2.35 63.96 5.85 18.77 39.67 49.52 18.60 48.53 0.00 0.912 1.002 LA2 40 2.23 68.96 14.44 23.96 44.41 58.95 26.31 59.51 0.00 0.597 0.452 LA3 50 2.12 77.82 23.22 28.91 52.68 65.22 32.24 67.22 0.00 0.428 0.340 LA16 30 5 3.83 60.07 0.03 7.61 40.95 28.06 1.61 31.17 0.24 259.389 6.049 LA17 Type A 40 5 2.24 62.63 0.25 12.74 47.02 40.24 7.49 41.05 0.24 31.011 3.414 LA18 50 5 1.83 71.37 2.93 25.02 56.53 49.37 18.55 49.05 0.24 1.104 0.739 LA19 30 10 5.03 57.10 0.11 0.44 42.88 14.87 1.69 17.60 0.49 18.57 5.91 LA20 40 10 3.02 77.18 0.83 25.41 62.47 36.59 1.90 38.77 0.49 11.651 1.963 LA21 50 10 2.50 90.15 1.97 30.35 81.08 34.66 1.80 36.73 0.49 5.710 1.631 LB1 30 2.24 75.95 8.15 27.41 50.97 47.61 22.88 29.29 0.00 0.897 0.546 LB2 40 2.02 77.95 17.26 37.49 66.49 55.51 34.46 35.21 0.00 0.435 0.303 LB3 50 1.69 87.23 20.55 45.62 75.92 61.89 39.22 38.77 0.00 0.415 0.285 LB16 30 5 2.71 59.70 0.30 11.50 52.30 35.40 5.70 22.20 0.19 19.28 2.47 LB17 Type B 40 5 2.18 72.00 5.50 31.40 63.60 47.40 21.00 28.30 0.19 1.257 0.612 LB18 50 5 1.79 73.80 16.80 38.50 64.70 50.00 31.90 29.60 0.19 0.42 0.29 LB19 30 10 3.61 60.55 0.05 2.80 50.70 34.95 1.20 18.85 0.38 170.590 15.261 LB20 40 10 2.53 84.30 0.70 21.30 72.10 51.00 8.80 29.40 0.38 11.42 1.81 LB21 50 10 2.03 83.30 7.50 37.40 68.90 54.30 24.80 31.50 0.38 1.075 0.556 LC1 30 1.39 39.89 18.40 44.70 76.26 24.52 21.70 30.27 0.00 0.077 0.043 LC2 40 1.46 53.20 32.60 57.15 85.64 32.30 34.67 39.75 0.00 0.058 0.037 LC3 Type C 50 1.21 58.84 40.39 60.58 88.32 29.98 39.63 38.39 0.00 0.052 0.034109.84*LC16 30 5 50.38 9.07 45.91 * 29.55 14.58 34.01 0.12 0.20 0.081.41BANIQL 3013654.00413138LC17 40 5 1.19 70.29 17.96 58.95 * 38.32 24.28 43.90 0.12 0.14 0.07 LC18 50 5 1.15 39.05 16.49 35.00 68.11 19.94 16.81 22.60 0.12 0.08 0.05103.03LC19 30 10 1.50 52.00 6.36 41.40 * 26.06 11.54 29.25 0.24 0.29 0.10112.86LC20 40 10 1.24 63.08 14.26 52.04 * 32.15 19.21 36.60 0.24 0.16 0.07162.08LC21 50 10 1.13 91.97 28.46 78.52 * 47.75 34.02 54.23 0.24 0.12 0.06*The high number is due to calibration error resulting from low magnesium / elemental content in the ore, which caused error in the measurement.BANIQL 3013654.004Example 11:

[0217] Leachates identified in Table 10 were heated to 60°C and the temperature was maintained at a value between 55°C - 65°C. Limestone (99% CaCO3) was added into the solution while stirred until pH is above 4.5. Once the pH reached 4.5 - 5.5, the solution was stirred for another 30 minutes before being filtered. After being filtered, the sample from each solution was taken to determine the elemental composition and concentration. The amount of CaCO3added relative to ore amount (%w / w), initial pH and final pH along with the overall extraction efficiency is presented in Table 11.BANIQL 3013654.004Table 11Overall extraction efficiency of each metal in neutral solution relative to the original ore Sample Ore Type H2SO4DAP (g) CaCOa pH initial pH final Ni Fe Al Mg Co Cr Mn LAI(comparative) 30 2.93 2.35 5.34 48.31 0.04 0.08 33.51 37.68 0.14 39.47 LA2(comparative) 40 5.25 2.23 5.05 64.24 0.09 0.29 35.20 50.28 1.10 54.52 LA3(comparative) 50 7.83 2.12 4.86 37.93 0.02 0.06 29.87 32.50 0.09 36.90 LA16 30 5 0.08 3.4 5.97 60.07 0.03 5.49 42.06 28.99 1.45 27.25Type ALA17 40 5 1.31 2.31 5.18 45.29 1.69 5.01 39.66 31.79 1.33 32.67 LA18 50 5 1.00 2.24 4.92 53.18 1.37 8.45 47.74 37.49 1.29 39.47 LA19 30 10 0.28 5.03 5.03 57.10 0.20 0.40 43.70 14.80 1.40 18.00 LA20 40 10 0.72 3.02 4.33 77.18 0.90 7.40 50.02 34.47 1.29 30.74 LA21 50 101.17 2.50 4.01 90.15 1.40 7.20 58.35 51.23 1.38 46.18LB1(comparative) 30 5.56 2.24 4.70 47.84 0.19 1.50 44.22 31.96 0.35 21.69 LB2(comparative) 40 8.28 2.02 4.83 30.61 0.18 1.65 41.32 25.35 0.30 21.92 LB3(comparative) 50 12.94 1.69 4.61 46.28 0.15 1.37 46.72 35.43 0.28 24.85 LB16 30 5 1.54 2.13 4.60 53.30 0.00 0.20 46.80 31.90 0.70 19.50Type BLB17 40 5 5.25 1.80 4.88 57.10 0.00 0.20 52.50 37.40 0.80 22.00 LB18 50 5 10.38 1.54 4.68 56.37 0.02 0.20 52.14 38.43 0.71 22.50 LB19 30 10 0.40 3.08 4.87 57.01 0.02 0.42 47.19 28.05 0.96 16.39 LB20 40 10 3.23 1.97 4.78 79.20 0.02 0.27 67.77 47.61 0.99 25.92 LB21 50 10 7.82 1.59 4.43 75.34 0.04 0.24 62.90 48.59 0.85 28.06 LC1(comparative) 30 13.97 1.39 4.88 12.19 0.00 0.04 43.35 8.99 0.07 15.85Type CLC2(comparative) 40 20.74 1.46 5.28 1.71 0.00 0.01 38.82 4.07 0.07 13.08BANIQL 3013654.004LC3(comparative) 50 30.02 1.21 5.14 1.84 0.00 0.01 49.82 3.25 0.07 13.70 LC16 30 5 9.69 1.41 5.29 48.90 0.21 7.98 99 22.14 0.52 23.88 LC17 40 5 16.28 1.19 5.32 16.36 0.07 5.45 83.24 15.82 0.49 21.92 LC18 50 5 22.12 1.15 5.27 30.95 0.01 3.05 73.57 16.76 0.36 22.34 LC19 30 10 8.77 1.50 5.22 35.76 0.01 3.43 84.40 17.94 0.60 22.20 LC20 40 10 20.54 1.24 5.32 30.87 0.01 1.84 82.09 15.70 0.45 18.97LC21 50 10 15.10 1.13 5.38 42.89 0.08 2.58 87.59 21.76 0.48 25.92BANIQL 3013654.004Example 12:

[0218] Four different phosphate salts: Monoammonium phosphate, Diammonium phosphate, phosphoric acid and calcium triphosphate were prepared to explore the effect of final pH and cation at a similar iron content in the ore to phosphate ratio, which is about 0.48 Fe I PO4 (mol I mol) ratio.

[0219] For experiment 1, 100 grams of Type C ore having the composition indicated in Tables A and B were prepared. For Sample 1: 20.59 grams of phosphoric (85% H3PO4) and 30 grams of sulfuric acid (93% H2SO4) were mixed with 400 grams of water. The solution was stirred for 15 minutes and heated up to 80-90 °C. The ore was added into the solution and mixed for 4 hours. After that, the solution was filtered and sampled for ICP-MS to determine the Ni / Fe ratio and extraction rate for each element.

[0220] The filtered solution was then reheated to 55-65 °C and limestone was added until the pH reached 4.5-5. The solution then was filtered from the solid and liquid was taken for ICP-MS to determine the remaining content of the element relative to the theoretical amount in the ore.

[0221] For experiment 2, 100 grams of Type C ore were prepared. For Sample 1: 24.17 grams of Monoammonium phosphate (MAP) and 30 grams of sulfuric acid (93% H2SO4) were mixed with 400 grams of water. The solution was stirred for 15 minutes and heated up to 80-90 °C. The ore was added into the solution and mixed for 4 hours. After that, the solution was filtered and sampled for ICP-MS to determine the Ni / Fe ratio and extraction rate for each element.

[0222] The filtered solution was then reheated to 55-65 °C and limestone was added until the pH reached 4.5-5. The solution then was filtered from the solid and liquid was taken for ICP-MS to determine the remaining content of the element relative to the theoretical amount in the ore.

[0223] For experiment 3, 100 grams of type C ore were prepared. For Sample 1: 27.54 grams of Diammonium phosphate (DAP) and 30 grams of sulfuric acid (93% H2SO4) were mixed with 400 grams of water. The solution was stirred for 15 minutes and heated up to 80-90 °C. The ore was added into the solution and mixed for 4 hours. After that, the solution was filtered and sampled for ICP-MS to determine the Ni / Fe ratio and extraction rate for each element.BANIQL 3013654.004

[0224] The filtered solution was then reheated to 55-65 °C and limestone was added until the pH reached 4.5-5. The solution then was filtered from the solid and liquid was taken for ICP-MS to determine the remaining content of the element relative to the theoretical amount in the ore.

[0225] For experiment 4: 100 grams of type C ore were prepared. For Sample 1: 65.17 grams of Calcium triphosphate (Ca3(PC>4)2) and 30 grams of sulfuric acid (93% H2SO4) were mixed with 400 grams of water. The solution was stirred for 15 minutes and heated to 80-90 °C. The ore was added into the solution and mixed for 4 hours. After that, the solution was filtered and sampled for ICP-MS to determine the Ni / Fe ratio and extraction rate for each element.

[0226] The filtered solution was then reheated to 55-65 °C and limestone was added until the pH reached 4.5-5. The solution then was filtered from the solid and liquid was taken for ICP-MS to determine the remaining content of the element relative to the theoretical initial amount in the ore.

[0227] The data is collected in Tables 12A & 12B.BANIQL 3013654.004Table 12ALeaching solution (Pre-LimestoneLeachate extraction efficiency after 4h Leaching (%) Mass ofreagentRatio re LativesFe / PO4to ore pH Ni / FeOre Type Reagent (mol / mol) (%) final ratio Ni Fe Al Mg Co Cr Mn H3PO40.48 20.59 1.24 0.77 62.61 11.60 63.86 99 39.26 26.60 47.09 MAP 0.48 24.17 2.03 0.62 68.34 4.25 49.71 99 31.65 8.68 36.97 Type CDAP 0.48 27.54 2.55 2.89 40.81 0.75 16.81 71.13 14.82 1.75 18.88Ca₃(PO₄)₂ 0.48 65.17 3.67 1.63 4.95 0.11 0.09 21.98 2.50 0.55 0.56Table 12BNeutral solution (Post limestone)Overall extraction efficiency of each metal in neutral solution relative to the original ore (%)Ore pHType R|eagent| CaCO3(%) initial pH final Ni Fe Al Mg Co Cr Mn 30.41.45H3PO411.08 4.76 3 0.21 2.11 55.98 19.13 0.61 22.9053.7MAP 11.94 1.75 4.55 53.72 0.67 2.50 99 20.01 0.56 14.76 Type C32.9DAP 15.28 2.15 4.43 32.92 0.01 0.03 49.00 11.71 0.22 13.60 CaPO₄ 18.67 4.03 4.99 8.67 0.08 0.06 31.21 2.19 0.48 0.75BANIQL 3013654.004EXAMPLE 13

[0228] Heap leach 1 (“HL1”): 100 grams of nickel bearing ore Type A (“Type A having the composition indicated in Tables A and B) was poured into the container with the PVDF filter 0.45 pm size on the bottom. Next, 400 grams of water was added into the container, followed by 30 grams of 93% sulfuric acid and 5 grams of 85% phosporic acid at room temperature and let all the solution percolated into the ore and eventually filtered through the bottom of the container. The solution was recycled back into the ore filled container everyday for the next 10 days.

[0229] A sample of the solution was taken after the solution finished dripping. The composition of the leachate was analyzed with ICP-MS and the pH measurement was taken daily. The results are presented in Table 13A.BANIQL 3013654.004Table 13AConcentration of analytes (g / L) in LeachateAnalytes Day 1 Day 2 Day 3 Day 4 Day 5 Day 6 Day 7 Day 8 Day 9 Day 10 Ni 0.666 1.211 1.632 1.952 2.003 2.102 2.081 2.67 2.692 2.718 Co 0.001 0.011 0.019 0.026 0.029 0.031 0.033 0.041 0.042 0.042 Fe 1.597 3.291 4.511 5.281 3.938 0.473 0.166 0.053 0.04 0.06 Mn 0.014 0.064 0.127 0.167 0.195 0.21 0.22 0.277 0.283 0.285 Cr 0.017 0.063 0.087 0.106 0.113 0.11 0.108 0.131 0.129 0.129 Al 0.183 0.37 0.457 0.518 0.554 0.505 0.491 0.48 0.419 0.367 Ca 94.5 0.038 0.016 0.047 0.062 0.001 0.081 0.008 0.015 0.007 Mg 1.934 5.143 8.535 9.912 11.53 13.26 13.12 14.72 15.35 15.59 Na 0.056 0.057 0.048 0.038 0.045 0.024 0.055 0.023 0.021 0.025 Ni / Fe ratio 0.417 0.368 0.362 0.37 0.509 4.444 12.536 50.377 67.3 45.3 Ni / Mg 0.344 0.235 0.191 0.197 0.174 0.159 0.159 0.181 0.175 0.174 ratioNi / Al ratio 3.647 3.275 3.573 3.77 3.616 4.163 4.239 5.562 6.424 7.403 pH 0.69 0.843 1.2 1.35 1.6 1.952 2.323 2.724 2.798 3.055

[0230] To estimate the extraction rate, the initial ore content before and after heap leached experiments of this example (HL1) is provided in Table 13B to estimate the extraction rate of each element.

[0231] 0.5 g of the nickel bearing ore samples was added into the flask, then, 60 ml of aqua regia (45 mL of HCl and 15 mL of HNO3) was mixed and poured into the flask. The sample was digested under aqua regia for 2 hours at 80°C. After that, the solution was cooled to room temperature and then the solution was filtered using Whatman filter paper 11 pm pore size. The filtrate was diluted with distilled water using a 100 mL volumetric flask and run through ICP-MS to obtain the wt% of the analytes and the results are collected in Table 13B.BANIQL 3013654.004Table 13BNickel ore HL1 Leachingwt% ExtractionType A Residue efficiencyNi 1.46 0.61 59%Co 0.03 0.01 47%Fe 11.69 10.69 9%Mn 0.21 0.13 37%Cr 0.21 0.18 16%Al 0.85 0.83 3%Mg 14.54 8.39 42%EXAMPLE 14

[0232] Heap leach 2 (“HL2”): 100 grams of nickel bearing ore Type A (“Type A having the composition indicated in Tables A and B) was poured into the container with the with the PVDF filter 0.45 pm size on the bottom. Next, 400 grams of water, followed by 30 grams of 93% sulfuric acid at room temperature and let all the solution permeated into the ore and eventually filtered through the bottom of the container. The solution was recycled back into the ore filled container everyday for the next 10 days.

[0233] Sample of the solution was taken after the solution finished dripping. The composition of the leachate was analyzed with ICP-MS and the pH measurement was taken daily. The results are presented on Table 14A.BANIQL 3013654.004Table 14AConcentration of analytes (g / L) in Leachate on HL2Analytes Day 1 Day 2 Day 3 Day 4 Day 5 Day 6 Day 7 Day 8 Day 9 Day 10 Ni 0.59 1.018 1.459 1.639 1.512 1.747 1.743 2.084 2.088 2.112 Co 0.003 0.009 0.018 0.022 0.022 0.027 0.028 0.034 0.034 0.034 Fe 1.806 2.753 3.64 4.467 4.095 4.492 4.434 4.919 4.88 4.899 Mn 0.011 0.058 0.114 0.143 0.142 0.172 0.18 0.217 0.221 0.223 Cr 0.018 0.052 0.075 0.09 0.085 0.095 0.098 0.114 0.114 0.114 Al 0.148 0.322 0.412 0.454 0.423 0.459 0.493 0.579 0.567 0.566 Ca 142.5 0.02 0.04 0.048 0.04 0.005 0.078 0.084 0.113 0.091 Mg 2.013 4.491 7.042 8.221 8.237 10.44 10.46 12.97 12.88 12.9 Na 0.059 0.036 0.055 0.038 0.037 0.025 0.054 0.011 0.001 0.007 Ni / Fe 0.327 0.37 0.401 0.367 0.369 0.389 0.393 0.424 0.428 0.431 ratioNi / Mg 0.293 0.227 0.207 0.199 0.184 0.167 0.167 0.161 0.162 0.164 ratioNi / Al 3.977 3.16 3.541 3.607 3.577 3.809 3.535 3.6 3.684 3.735 ratioPH 0.68 0.9 1.42 1.26 1.456 1.621 1.837 1.973 2.074 2.155

[0234] To estimate the extraction rate, the initial ore content before and after the heap leached experiments of this Example (HL2) is provided below on Table 14B to estimate the extraction rate of each element.

[0235] 0.5 g of the Type A nickel bearing ore samples (“Type A having the composition indicated in Tables A and B) was added into the flask, then, 60 ml of aqua regia (45 mLof HCl and 15 mL of HNO3) was mixed and poured into the flask. The sample was digested under aqua regia for 2 hours at 80°C. After that, the solution was cooled to room temperature and then the solution was filtered using Whatman filter paper 11 pm pore size. The filtrate was diluted with distilled waterBANIQL 3013654.004using a 100 mL volumetric flask and run through ICP-MS to obtain the wt% of the analytes.Table 14BNickel ore HL2 Leachingwt% ExtractionType A Residue efficiencyNi 1.46 0.89 39%Co 0.03 0.02 30%Fe 11.69 11.15 5%Mn 0.21 0.16 22%Cr 0.21 0.21 3%Al 0.85 0.82 3%Mg 14.54 12.69 13%EXAMPLE 15

[0236] Heap leach 3 (“HL3”): 100 grams of nickel bearing ore Type A (“Type A having the composition indicated in Tables A and B) was poured into the container with the PVDF filter 0.45 pm size on the bottom. Next, 400 grams of water, followed by 30 grams of 85% phosphoric acid at a room temperature was added into the container and let all the solution permeated into the ore and eventually filtered through the bottom of the container. The solution was recycled back into the ore filled container everyday for the next 10 days.

[0237] A sample of the solution was taken after the solution finished dripping. The composition of the leachate was analyzed with ICP-MS and the pH measurement was taken daily. The results are presented in Table 15A.BANIQL 3013654.004Table 15AConcentration of analytes (g / L)in Leachate on HL3Analytes Day 1 Day 2 Day 3 Day 4 Day 5 Day 6 Day 7 Day 8 Day 9 Day 10 Ni 0.726 1.049 1.279 1.355 1.085 1.084 1.102 1.18 1.078 1.047 Co 0.002 0.003 0.005 0.006 0.007 0.01 0.006 0.008 0.006 0.006 Fe 6.645 7.428 8.257 6.258 0.328 0.098 0.014 0.007 0.007 0.004 Mn 0.035 0.045 0.062 0.068 0.051 0.521 0.049 0.06 0.046 0.557 Cr 0.012 0.031 0.041 0.037 0.033 0.026 0.012 0.01 0.001 0.002 Al 0.279 0.339 0.381 0.279 0.162 0.046 0.017 0.015 0.002 0.047 Ca 0.028 0.02 0.037 0.017 0.113 0.062 0.131 0.108 0.109 0.097 Mg 1.31 2.25 3.392 4.204 5.13 6.008 5.919 6.632 6.752 7.635 Na 0.187 0.178 0.198 0.168 0.001 0.039 0.005 0.001 0.01 0.028 Ni / Fe ratio 0.109 0.141 0.155 0.217 3.308 11.061 78.714 168.571 154 261.75 Ni / Mg ratio 0.554 0.466 0.377 0.322 0.212 0.18 0.186 0.178 0.16 0.137 Ni / Al ratio 2.597 3.097 3.354 4.849 6.697 23.809 65.767 77.577 586.658 22.276 pH 1.547 1.828 2.114 2.483 2.25 3.262 3.914 3.893 4.541 4.62

[0238] To estimate the extraction rate, the initial ore content before and after heap leached experiments of this example (HL3) is provided below in Table 16B to estimate the extraction rate of each element.

[0239] 0.5 g of the nickel bearing ore samples (“Type A having the composition indicated in Tables A and B) was added into the flask, then, 60 ml of aqua regia (45 mL of HCl and 15 mL of HNO3) was mixed and poured into the flask. The sample was digested under aqua regia for 2 hours at 80°C. After that, the solution was cooled to room temperature and then the solution was filtered using Whatman filter paper 11 pm pore size. The filtrate was diluted with distilled water using a 100 mL volumetric flask and run through ICP-MS to obtain the wt% of the analytes. Results are presented in Table 15B.BANIQL 3013654.004Table 15BNickel ore HL3 Leachingwt% ExtractionType A Residue efficiencyNi 1.46 1.07 27%Co 0.03 0.02 14%Fe 11.69 8.74 25%Mn 0.21 0.17 19%Cr 0.21 0.17 22%Al 0.85 0.63 27%Mg 14.54 10.71 26%EXAMPLE 16

[0240] Heap leach 4 (“HL4”): 100 grams of nickel bearing ore Type A (“Type A having the composition indicated in Tables A and B) was poured into the container with the filter on the bottom. Next, a solution containing 400 grams of water and 30 grams of 93% sulfuric acid and 10 grams of 85% phosphoric acid at a room temperature was premixed and added into the container and let all the solution permeated into the ore and eventually filtered through the bottom of the container. The solution was recycled back into the ore filled container daily for the next 7 days.

[0021] Sample of the solution was taken after the solution finished dripping. The composition of the leachate was analyzed with ICP-MS and the pH measurement was taken daily. The results are presented on Table 16A.BANIQL 3013654.004Table 16AConcentration of analytes (g / L) in Leachate on HL4Analyte Day 1 Day 2 Day 3 Day 4 Day 5 Day 6 Day 7 Day 8 Day 9 Day 10 Ni 1.135 2.108 2.288 2.347 278 2.662 2.679 2.448 2.95 3011 Co 0.004 0.017 0.032 0.033 0042 0.041 0.041 0.038 0.044 0041 Fe 7.649 11.432 6.725 7.05 1 188 0.18 0.061 0.027 0.022 0032 Mn 0046 0 13 0211 0218 0279 0 195 0 199 0255 0318 0281 Cr 0.035 0.092 0.131 0.134 0121 0.122 0.111 0.086 0.03 0016 Al 0.395 0.538 0.621 0.639 0549 0.344 0.149 0.063 0.01 0004 Ca 0.029 0.032 0.098 0.085 0062 0.022 0.035 0.077 0.519 0071 Mg 2.361 7.352 12.935 13.328 17.325 18.032 18.364 17.139 22.621 20.681 Na 0.2 0.196 0.004 0.01 0025 0.036 0.037 0.188 0.047 0014 Ni / Fe 0.148 0.184 0.34 0.333 234 14.768 43.734 89.305 136.075 93.352 ratioNi / Mg 0.481 0.287 0.177 0.176 016 0.148 0.146 0.143 0.13 0146 ratioNi / AI 2.875 3.916 3.683 3.671 5064 7.746 18.031 39.032 307.181 81509 ratio 7 PH 0.735 0.886 1.149 1.422 1 998 2.528 2.986 3.222 3.941 411

[0242] To estimate the extraction rate, the initial ore content before and after heap leached experiments of this example (HL4) is provided below on Table 16B to estimate the extraction rate of each element.

[0243] 0.5 g of the nickel bearing ore samples (“Type A having the composition indicated in Tables A and B) was added into the flask, then, 60 ml of aqua regia (45 mL of HCl and 15 mL of HNO3) was mixed and poured into the flask. The sample was digested under aqua regia for 2 hours at 80°C. After that, the solution was cooled to room temperature and then the solution was filtered using Whatman filter paper 11 pm pore size. The filtrate was diluted with distilled water using a 100 mL volumetric flask and run through ICP-MS to obtain the wt% of the analytes. Results are presented in Table 16B.BANIQL 3013654.004Table 16BNickel ore HL4 Leachingwt% ExtractionType A ResidueefficiencyNi 1.46 0.58 60%Co 0.03 0.01 63%Fe 11.69 11.23 4%Mn 0.21 0.09 56%Cr 0.21 0.19 11%Al 0.85 0.65 24%Mg 14.54 4.14 72%EXAMPLE 17

[0244] Heap leach 5 (“HL5”): 100 grams of nickel bearing ore Type B (composition indicated in Tables A and B) was poured into the container with the filter on the bottom. Next, a solution containing 400 grams of water and 30 grams of 93% sulfuric acid and 10 grams of 85% phosphoric acid at a room temperature was premixed and added into the container and let all the solution permeated into the ore and eventually filtered through the bottom of the container. The solution was recycled back into the ore filled container everyday for the next 10 days.

[0245] A sample of the solution was taken after the solution finished dripping. The composition of the leachate was analyzed with ICP-MS and the pH measurement was taken daily. The results are presented in Table 17A.Table 17AConcentration of analytes (g / L) in LeachateAnalyte Day 1 Day 2 Day 3 Day 4 Day 5 Day 6 Day 7 Day 8 Day 9 Day 10 Ni 1.085 1.093 1.599 1.77 1.867 2.558 2.968 3.03 3.049 3.068 Co 0.013 0.014 0.024 0.029 0.031 0.041 0.05 0.052 0.053 0.054 Fe 2.556 2.559 3.531 4.468 3.929 3.21 2.575 1.819 1.385 0.988 Mn 0.033 0.039 0.067 0.09 0.098 0.128 0.156 0.164 0.168 0.17 Cr 0.092 0.091 0.139 0.168 0.176 0.243 0.27 0.275 0.278 0.276 Al 0.552 0.577 0.804 0.921 0.967 1.19 1.289 1.324 1.322 1.331 Ca 0.075 0.075 0.07 0.063 0.117 0.13 0.162 0.188 0.199 0.155BANIQL 3013654.004Mg 4.684 4.773 7.747 9.057 9.554 12.896 13.869 14.389 14.51 14.854 Na 0.039 0.029 0.029 0.029 0.048 0.048 0.05 0.061 0.062 0.055 Ni / Fe 0.4248 0.4273 0.4528 0.3961 0.4751 0.7969 1.1523 1.6656 2.2011 3.105 ratioNi / Mg 0.2318 0.2291 0.2064 0.1954 0.1954 0.1983 0.214 0.2105 0.2101 0.2066 ratioNi / Al 1.9659 1.8942 1.9875 1.9215 1.9308 2.1492 2.3015 2.2889 2.307 2.306 ratiopH 0.609 0.921 1.236 1.654 1.617 1.764 1.776 1.896 1.89 2.083

[0246] To estimate the extraction rate, the initial ore content before and after heap leached experiments of this example (HL5) is provided below in Table 17B to estimate the extraction rate of each element.

[0247] 0.5 g of the nickel bearing ore samples (“Type B having the composition indicated in Tables A and B) was prepared, was added into the flask, then, 60 ml of aqua regia (45 mL of HCl and 15 mL of HNO3) was mixed and poured into the flask. The sample was digested under aqua regia for 2 hours at 80°C. After that, the solution was cooled to room temperature and then the solution was filtered using Whatman filter paper 11 pm pore size. The filtrate was diluted with distilled water using a 100 mL volumetric flask and run through ICP-MS to obtain the wt% of the analytes.BANIQL 3013654.004Table 17BNickel ore HL5 Leachingwt% ExtractionType B Residue efficiencyNi 1.43 0.62 56%Co 0.04 0.02 45%Fe 14.86 15.51 -4%Mn 0.23 0.13 41%Cr 0.33 0.28 17%Al 1.19 0.60 50%Mg 8.42 1.93 82%EXAMPLE 18

[0248] Heap leach 6 (“HL6”): Another type of Nickel bearing ore (“Type C”) (“Type C having the composition indicated in Tables A and B) was poured into the container with the filter on the bottom. Next, a solution containing 400 grams of water and 30 grams of 93% sulfuric acid and 10 grams of 85% phosphoric acid at a room temperature was premixed and added into the container and let all the solution permeated into the ore and eventually filtered through the bottom of the container. The solution was recycled back into the ore filled container everyday for the next 10 days.

[0249] A sample of the solution was taken after the solution finished dripping. The composition of the leachate was analyzed with ICP-MS and the pH measurement was taken daily. The results are presented in Table 18.BANIQL 3013654.004Table 18Concentration of analytes (g / L) in LeachateAnalytes Day 1 Day 2 Day 3 Day 4 Day 5 Day 6 Day 7 Day 8 Day 9 Day 10 Ni 0.135 0.158 0.346 0.386 0.418 0.600 0.745 0.775 0.819 0.863 Co 0.002 0.002 0.008 0.010 0.011 0.014 0.021 0.022 0.024 0.026 Fe 0.811 1.066 2.992 3.316 3.681 5.215 6.488 6.809 7.268 7.610 Mn 0.013 0.018 0.058 0.073 0.081 0.109 0.140 0.148 0.159 0.168 Cr 0.017 0.022 0.069 0.080 0.087 0.128 0.155 0.164 0.174 0.185 Al 0.719 0.822 1.533 1.666 1.905 2.470 2.807 2.891 3.066 3.203 Ca 0.092 0.085 0.087 0.093 0.086 0.158 0.212 0.213 0.168 0.173 Mg 0.473 0.545 1.200 1.322 1.496 2.011 2.259 2.333 2.467 2.559 Na 0.048 0.026 0.026 0.029 0.030 0.045 0.052 0.052 0.051 0.051 Ni / Fe 0.1667 0.1481 0.1157 0.1166 0.1135 0.1150 0.1148 0.1138 0.1127 0.1134 ratioNi / Mg 0.2861 0.2896 0.2886 0.2924 0.2793 0.2983 0.3296 0.3322 0.3319 0.3374 ratioNi / Al 0.1880 0.1921 0.2259 0.2320 0.2194 0.2429 0.2653 0.2681 0.2671 0.2695 ratiopH 0.462 0.736 0.787 0.853 0.872 0.941 0.837 0.88 0.871 0.973

Claims

BANIQL 3013654.004CLAIMSWhat is claimed is:

1. A process for extracting nickel from a feed ore comprising a mineralized form of iron and a mineralized form of nickel, the process comprising (i) treating the feed ore with an acid system in a reaction mixture comprising a phosphate source and a mineral acid other than phosphoric acid to form a leached ore and a leachate comprising nickel extracted from the ore and (ii) separating the leachate from the leached ore.

2. The process of claim 1 wherein the process is carried out at a pressure of less than 2 standard atmospheres.

3. The process of claim 1 wherein the process is a heap leaching process in which the acid system is dispersed onto a heap of the feed ore and the nickel-bearing leachate trickles (percolates) slowly through the heap under the force of gravity until it reaches a collection pad or other collection device at the base of the heap.

4. The process of claim 1 wherein the process is an agitated atmospheric process carried out in a reaction vessel.

5. The process of any previous claim wherein the phosphate source is selected from the group consisting of phosphoric acid and phosphate salts.

6. The process of any previous claim wherein the phosphate source is selected from the group consisting of mono, di and trisodium phosphates, dicalcium and tricalcium phosphate, hydroxapetite, mono, di and triammonium phosphates, ammonium calcium phosphate, di or tri-magnesium phosphate, mixed anion phosphates, superphosphates, other phosphate-bearing compositions or minerals, and combinations thereof.

7. The process of any previous claim wherein the molar ratio of the phosphate source to iron comprised by the feed ore in the reaction mixture is at least 1:50, 1:40, 1:30, 1:20, 1:10, 1:7.5, 1:5, 1:2, or 1:1, respectively.

8. The process of any previous claim wherein the molar ratio of the phosphate source to iron comprised by the feed ore in the reaction mixture is less than 1:5, respectively.

9. The process of any previous claim wherein the molar ratio of the phosphate source to the combined amount of iron and aluminum comprised by theBANIQL 3013654.004feed ore in the reaction mixture is at least 1:50, 1:40, 1:30, 1:20, 1:10, 1:7.5, 1:5, 1:2, or 1:1, respectively.

10. The process of any previous claim wherein the molar ratio of the phosphate source to the combined amount of iron and aluminum comprised by the feed ore in the reaction mixture is less than 1:5, respectively.

11. The process of any previous claim wherein the weight ratio of the combined amount of mineral acid(s) other than phosphoric acid comprised by the acid system to the amount of phosphoric acid comprised by the acid system is greater than 1:1, 1.5:1, 2:1, 2.5:1, 3:1, 4:1, or 5:1, respectively.

12. The process of any previous claim wherein the weight ratio of the combined amount of mineral acid(s) other than phosphoric acid comprised by the acid system to the amount of phosphoric acid comprised by the acid system is less than 10:1, 9:1, 8:1, 7:1, 6:1, or 5:1, respectively.

13. The process of any previous claim wherein the weight ratio of phosphoric acid to feed ore in the reaction mixture is at least 1:100, 1:50, 1:25, 1:20, 1:10, or 1:5, respectively.

14. The process of any previous claim wherein the weight ratio of phosphoric acid to feed ore in the reaction mixture does not exceed 1:5, 1.7.5, 1:10, 1:15, or 1:20, respectively.

15. The process of any previous claim wherein the mineral acids other than phosphoric acid comprised by the acid system are selected from the group consisting of hydrochloric acid, nitric acid, sulfuric acid and combinations thereof.

16. The process of any previous claim wherein the mineral acids other than phosphoric acid comprised by the acid system are selected from the group consisting of hydrochloric acid, sulfuric acid and combinations thereof.

17. The process of any previous claim wherein the mineral acids other than phosphoric acid comprised by the acid system is sulfuric acid.

18. The process of any previous claim wherein the feed ore comprises at least 5 wt% iron.

19. The process of any previous claim wherein the feed ore comprises at least 25 wt% iron.

20. The process of any previous claim wherein the feed ore comprises no more than 3.5 wt% nickel.BANIQL 3013654.00421. The process of any previous claim wherein the feed ore comprises no more than 1.5 wt% nickel.

22. The process of any previous claim wherein the reaction mixture is under a pressure of less than 1.25 standard atmospheres (<1140 mm Hg).

23. The process of any previous claim wherein the reaction mixture is under a pressure that does not exceed standard atmospheric pressure (760 mm Hg).

24. The process of any previous claim wherein the reaction mixture is at a temperature not in excess of 120 °C.

25. The process of any previous claim wherein the reaction mixture is at a temperature not in excess of 100 °C.

26. The process of any previous claim wherein the feed ore further comprises a mineralized form of cobalt and the leachate comprises cobalt extracted from the phosphoric acid treated ore.

27. The process of any previous claim wherein the feed ore comprises a lateritic ore.

28. The process of any previous claim wherein the feed ore comprises limonite ore.

29. The process of any previous claim wherein the feed ore comprises saprolite ore.

30. The process of any previous claim wherein the process further comprises electrowinning nickel from the separated leachate.

31. The process of any previous claim wherein the process further comprises electrowinning cobalt from the separated leachate.

32. The process of any previous claim wherein the concentration of phosphate in the reaction mixture is within the range of 0.01 M to 1 M.

33. The process of any previous claim wherein the concentration of phosphate in the reaction mixture is within the range of 0.05 M to 0.5 M.

34. The process of any previous claim wherein the concentration of phosphate in the reaction mixture is within the range of 0.1 M to 0.35 M.

35. The process of any previous claim wherein the reaction mixture comprises a source of ammonium and the concentration of the ammonium in the reaction mixture is within the range of 0.01 M to 1 M.BANIQL 3013654.00436. The process of any previous claim wherein the reaction mixture comprises a source of ammonium and the concentration of the ammonium in the reaction mixture is within the range of 0.05 M to 0.75 M.

37. The process of any previous claim wherein the reaction mixture comprises a source of ammonium and the concentration of the ammonium in the reaction mixture is within the range of 0.075 M to 0.5 M.

38. The process of any previous claim wherein the reaction mixture is at a pH in the range of pH 1 to pH 4.5.

39. The process of any previous claim wherein the reaction mixture is at a pH of at least 1.5.

40. The process of any previous claim wherein the reaction mixture is at a pH of at least 2.

41. The process of any previous claim wherein the reaction mixture is at a pH of at least 3.

42. The process of any previous claim wherein the reaction mixture is at a pH of less than 4.

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