Methods of solvent extraction having reduced crud or improved phase disengagement times

Abstract

Methods of solvent extraction are provided, including methods that exhibit improved phase disengagement times or reduced crud. The methods may include contacting an aqueous phase and / or an organic phase with a phase disengagement agent. The phase disengagement agent may improve a phase disengagement time. The methods may include contacting an aqueous phase and / or an organic phase with a crud reducing agent.

Description

METHODS OF SOLVENT EXTRACTION HAVING REDUCED CRUD OR IMPROVED PHASE DISENGAGEMENT TIMESCross-reference to Related Applications

[0001] This application claims priority to Finnish Patent Application No. 20245377, filed March 28, 2024, and U.S. Patent Application No. 63 / 550,935, filed February 7, 2024, which is incorporated by reference herein.Field of the Disclosure

[0002] This disclosure relates to methods of solvent extraction, including methods having improved phase disengagement times, or reduced crud.Background

[0003] Solvent extraction, which may be referred to as liquid-liquid extraction or partitioning, may be used to separate a compound based on solubility, such as the solubilities of the compounds’ parts. Typically, solvent extraction relies on two liquids with no, or limited, solubility in each other, such as water and an organic liquid.

[0004] Solvent extraction processes usually include extraction and a stripping reaction. In an extraction stage, a solvent and an aqueous phase are separated in a settler. The phase continuity and / or the time of phase separation, which may be referred to as the phase disengagement time, can be operating parameters that inform the efficiency of extraction processes, such as copper extraction processes. As a result, reducing disengagement time and / or improving phase separation can have a number of advantages, such as reducing environmental impact through improved phase separation, reducing operating costs caused by extractant losses while reducing maintenance, and / or improving revenue.

[0005] Solvent extraction plants typically suffer from an accumulation of solids, w hich is commonly referred to as “crud”. The crud may be composed mainly of silica. The presence of crud can influence a number of parameters, such as the continuity of organic- aqueous phases, emulsion stability, and, therefore, phase disengagement time. The presence of crud also can increase the cost of operation, possibly due to the loss of organic phases.

[0006] The removal of crud from a settler or other part of a solvent extraction process or apparatus can be difficult and / or laborious, and can require the shutdown of a plant, which can further increase losses.

[0007] There remains a need for improved methods of solvent extraction, including methods that enjoy reduced phase disengagement times, and methods that eliminate or reduce crud. There also remains need for improved compositions, such as blends of surface active agents, that reduce phase disengagement times, and eliminate or reduce crud.Brief Summary

[0008] Provided herein are methods of solvent extraction with reduced phase disengagement times, and phase disengagement agents that can reduce phase disengagement times by a surprising and unexpected extent. Also provided herein are compositions and methods of solvent extraction that can reduce or eliminate crud, such as by preventing or reducing further polymerization and / or aggregation of silica by removing excess silica from an aqueous phase, preferably before contacting an aqueous phase and an organic phase. The compositions and methods provided herein may include or use, respectively, a phase disengagement agent or crud reducing agent that includes a first and a second non-ionic surface active agent, wherein the first non-ionic surface active agent includes a polyoxyethylene sorbitan monooleate, and the second non-ionic surface active agent includes a copolymer, such as non-ionic block (e g., triblock) copolymer.

[0009] By reducing phase disengagement times and / or reducing or eliminating crud formation, embodiments of the methods provided herein can reduce the environmental impact of solvent extraction, reduce operating costs, and / or free up plant capacity.

[0010] In one aspect, methods of solvent extraction having reduced phase disengagement times are provided. In some embodiments, the methods include providing an aqueous phase: contacting the aqueous phase and an organic phase to form a mixture; contacting (i) the aqueous phase, the organic phase, or the mixture and (ii) a phase disengagement agent; and separating the aqueous phase and the organic phase; wherein the phase disengagement agent includes (a) a first non-ionic surface active agent that includes a polyoxyethylene sorbitan monooleate, and (b) a second non-ionic surface active agent that includes a copolymer. The separating of the aqueous phase and the organic phase may be completed at a phase disengagement time that at least 2 %, at least 3 %, at least 4 %. at least 5 %, at least 10 %, at least 15 %, at least 20 %, at least 25 %, at least 30 %, at least 35 %, at least 40 %, at least 45 %, at least 50 %, at least 60 %, at least 70 %, at least 80 %, at least 90 %, about 2 % to about 90 %, about 2 % to about 80 %, about 2 % to about 70 %, about 2 % to about 60 %. about 2 % to about 50 %, about 2 % to about 45 %. about 2 % to about 40 %, about 2 % to about 35 %, about 2 % to about 30 %, about 2 % to about 25 %, about2 % to about 20 %. about 2 % to about 15 %, about 2 % to about 10 %, about 2 % to about 5 %, about 2 % to about 4 %, about 5 % to about 10 %, about 40 % to about 90 %, or about 40 % to about 80 % less than a time to separate the aqueous phase and the organic phase in the absence of the phase disengagement agent, or in the presence of a comparative phase disengagement agent.

[0011] In another aspect, methods of solvent extraction that include crud reduction or elimination are provided. In some embodiments, the methods include providing an aqueous phase; contacting the aqueous phase and a crud reducing agent; and removing at least a portion of the first amount of silica from the aqueous phase to form a treated aqueous phase comprising a second amount of silica; wherein the crud reducing agent includes (a) a first non-ionic surface active agent that includes a polyoxyethylene sorbitan monooleate, and (b) a second non-ionic surface active agent that includes a copolymer. The second amount of silica may be at least 2 %, at least 5 %, at least 10 %, at least 1 %, at least 20 %, at least 25 %, or at least 50 % less than the first amount of silica. The methods also may include contacting the treated aqueous phase and an organic phase; and separating the treated aqueous phase and the organic phase.

[0012] In a further aspect, compositions are provided, such as phase disengagement agents or crud reducing agents. In some embodiments, the compositions include (a) a first non-ionic surface active agent that includes any of those described herein, such as a sorbitol based surface active agent, and (b) a second non-ionic surface active agent that includes a copolymer. In some embodiments, the first non-ionic surface active agent and the second non-ionic surface active agent are present in the compositions at a weight ratio of from about 5:95 to about 45:55, about 10:90 to about 45:55, about 20:80 to about 45:55, about 25:75 to about 45:55, about 25:75 to about 40:60, or about 30:70 to about 40:60 (first non-ionic surface active agent : second non-ionic surface active agent).

[0013] Additional aspects will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the aspects described herein. The advantages described herein may be realized and attained by means of the elements and combinations particularly pointed out in the appended claims. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive.Detailed Description

[0014] Provided herein are methods of solvent extraction. In some embodiments, the methods exhibit improved phase disengagement times. In some embodiments, the methods reduce or eliminate crud.

[0015] In some embodiments, the methods include providing an aqueous phase, contacting the aqueous phase and an organic phase to form a mixture, and then separating the aqueous phase and the organic phase. The contacting of the aqueous phase and the organic phase, and the separating of the aqueous phase and the organic phase may be achieved by any known technique, including solvent extraction techniques known in the art.

[0016] Improved Phase Disengagement Times

[0017] In some embodiments, the methods include contacting (1) an aqueous phase, an organic phase, or a mixture of the organic phase and the aqueous phase and (2) a phase disengagement agent. For example, an aqueous phase may be contacted with all or a portion of an amount of a phase disengagement agent before and / or after the contacting of the aqueous phase and an organic phase (e.g., an aqueous phase may be contacted with (i) a first portion of a phase disengagement agent before the contacting of the aqueous phase and an organic phase, and (ii) a second portion of a phase disengagement agent after the contacting of the aqueous phase and an organic phase). As a further example, a mixture of an aqueous phase and an organic phase may be contacted with a phase disengagement agent.

[0018] In some embodiments, the contacting of an aqueous phase and an organic phase includes mixing the aqueous phase and organic phase. Any mixing apparatus may be used to mix the aqueous phase and the organic phase. The mixing may occur for a mixing time, which may be a predetermined mixing time, and the contacting of the phase disengagement agent and the aqueous phase, the organic phase, or the mixture thereof may occur before the mixing time commences, or after at least 25 %, at least 50 %, at least 60 %, at least 70 %, at least 80 %, or at least 90 %, or after 100 % of the mixing time has transpired. For example, an aqueous phase and an organic phase may be subjected to mixing for a predetermined mixing time of one minute, and the mixture and the phase disengagement agent are contacted 30 seconds after the onset of mixing.

[0019] In some embodiments, the methods include subjecting an aqueous phase to leaching prior to the contacting of the aqueous phase and an organic phase, and the aqueous phase and the phase disengagement agent are (i) contacted after the leaching, or (ii) contacted after the leaching and before the contacting of the aqueous phase and the organic phase. As used herein, the term “leaching” refers to and includes (i) a process or portion of a processthat includes extracting a substance from a medium by dissolving the substance with a solvent or lixiviant, and (ii) bioleaching (e.g., microbial leaching), which generally includes extracting a material, such as a metal from an ore, with an organism.

[0020] In some embodiments, the separating of the aqueous phase and the organic phase is completed ( / .e., complete phase separation, see Example 1) at a phase disengagement time that is at least 2 %, at least 3 %, at least 4 %, at least 5 %, at least 10 %, at least 15 %. at least 20 %. at least 25 %, at least 30 %, at least 35 %, at least 40 %. at least 45 %, at least 50 %, at least 60 %, at least 70 %, at least 80 %, at least 90 %, about 2 % to about 90 %, about 2 % to about 80 %, about 2 % to about 70 %, about 2 % to about 60 %, about 2 % to about 50 %, about 2 % to about 45 %, about 2 % to about 40 %, about 2 % to about 35 %, about 2 % to about 30 %, about 2 % to about 25 %, about 2 % to about 20 %. about 2 % to about 15 %, about 2 % to about 10 %, about 2 % to about 5 %, about 2 % to about 4 %, about 5 % to about 10 %, about 40 % to about 90 %, or about 40 % to about 80 % less than a time to separate the aqueous phase and the organic phase ( / .e., achieve the same complete phase separation) in the absence of the phase disengagement agent, or in the presence of a comparable phase disengagement agent. For example, if the time to separate an aqueous phase and an organic phase in the absence of a phase disengagement agent is 100 seconds, then the contacting of the aqueous phase with a phase disengagement agent may reduce the time to separate the aqueous phase and the organic phase (z.e., the phase disengagement time) to 75 seconds or less (a reduction of at least 25 %), 70 seconds or less (a reduction of at least 30 %), etc.

[0021] An aqueous phase, an organic phase, or a mixture may be contacted with any effective amount of a phase disengagement agent. In some embodiments, a phase disengagement agent is present at an amount, relative to the aqueous phase, the organic phase, or the mixture, of about 5 ppm to about 30 ppm, about 5 ppm to about 25 ppm, about 5 ppm to about 20 ppm, about 5 ppm to about 15 ppm, about 5 ppm to about 10 ppm, about 5 ppm to about 1,000 ppm, 100 ppm to about 1,000 ppm, about 100 ppm to about 700 ppm, about 100 ppm to about 600 ppm, about 200 ppm to about 600 ppm, about 300 ppm to about 600 ppm. about 100 ppm to about 500 ppm. about 100 ppm to about 400 ppm, or about 100 ppm to about 300 ppm.

[0022] Crud Reduction

[0023] In some embodiments, the methods provided herein include providing an aqueous phase, contacting the aqueous phase and a crud reducing agent; and removing at least a portion of the first amount of silica from the aqueous phase to form a treated aqueousphase that includes a second amount of silica. The methods also may include contacting the treated aqueous phase and an organic phase, and separating the treated aqueous phase and the organic phase. The contacting of a treated aqueous phase and an organic phase, as described herein, may include mixing the aqueous phase and the organic phase.

[0024] The crud reducing agent may ease and / or facilitate the elimination or reduction of crud in the aqueous phase. For example, a crud reducing agent may increase the average particle size of silica-containing aggregates, thereby permitting sedimentation, increasing the rate of sedimentation, or a combination thereof. For example, the first amount of silica may be present in the aqueous phase in the form of particles having a first average particle size, as measured by dynamic light scattering, and after the contacting of the aqueous phase and the crud reducing agent (e.g., at least 5 seconds, at least 10 seconds, or at least 20 seconds after the contacting of the aqueous phase and the crud reducing agent), the first amount of silica may be present in the aqueous phase in the form of particles having a second average particle size, as measured by dynamic light scattering, and the second average particle size may be at least 2 times, at least 3 times, at least 4 times, at least 5 times, or at least 10 times greater than the first average particle size.

[0025] The removing of at least a portion of the first amount of silica from the aqueous phase to form a treated aqueous phase that includes a second amount of silica may be achieved by any known technique, including conventional solid-liquid separation techniques. The technique may be an active technique, a passive technique, or a combination thereof. A '‘passive technique” relies on gravity to achieve sedimentation, whereas an '‘active technique” relies on at least one force other than gravity. For example, the removing of at least a portion of the first amount of silica may include centrifuging the aqueous phase, which is an “active technique”. The sedimentation, as described herein, may occur and / or have an increased rate due, at least in part, to an increased particle size of silica-containing aggregates. After sedimentation has reached a desired level, the silica, e.g., silica-containing aggregates, may be removed by any known technique, such as decanting.

[0026] In some embodiments, the first amount of silica in the aqueous phase is about 0.5 g / L to about 3 g / L. about 0.5 g / L to about 2 g / L. or about 0.5 g / L to about 1.5 g / L. In some embodiments, the second amount of silica is at least 2 %, at least 5 %, at least 10 %, at least 15 %, at least 20 %, at least 25 %, at least 30 %, at least 35 %, at least 40 %, at least 45 %, at least 50 %, at least 60 %, at least 70 %. at least 80 %, at least 85 %, at least 90 %, at least 95 %. or at least 99 % less than the first amount of silica. For example, if the firstamount of silica in the aqueous phase is 2 g / L and the second amount of silica is at least 99 % less than the first amount of silica, then the second amount of silica is 0 g / L to about 0.02 g / L.

[0027] An aqueous phase generally may be contacted with any effective amount of a crud reducing agent. For example, an effective amount may include a concentration less than or equivalent to the critical micelle concentration (CMC) of a crud reducing agent. In some embodiments, after the contacting of the aqueous phase and the crud reducing agent, the crud reducing agent is present in the aqueous phase at an amount of about 0. 1 ppm to about 400 ppm, about 0. 1 ppm to about 300 ppm, about 0. 1 ppm to about 250 ppm, about 0.1 ppm to about 200 ppm, about 0. 1 ppm to about 180 ppm, about 0.1 ppm to about 160 ppm, about 0. 1 ppm to about 140 ppm, about 0. 1 ppm to about 120 ppm, about 0. 1 ppm to about 100 ppm, about 0.1 ppm to about 80 ppm, about 0. 1 ppm to about 60 ppm, about 0. 1 ppm to about 40 ppm, about 0.1 ppm to about 20 ppm, about 0.1 ppm to about 12 ppm, about 1 ppm to about 10 ppm, about 2 ppm to about 10 ppm, about 3 ppm to about 10 ppm, about 4 ppm to about 10 ppm, about 5 ppm to about 10 ppm, about 6 ppm to about 10 ppm, about 7 ppm to about 10 ppm, about 8 ppm to about 10 ppm, about 9 ppm to about 10 ppm, about 2 ppm to about 8 ppm. about 3 ppm to about 7 ppm. or about 4 ppm to about 6 ppm.

[0028] When performed, the centrifuging of an aqueous phase may include subjecting the aqueous phase to an effective gravitational force equivalent (g-force), such as up to 20,000. up to 15,000, or up to 10,000. In some embodiments, the centrifuging of an aqueous phase includes subjecting the aqueous phase to a g-force of about 10 to about 8,000, about 100 to about 8,000, about 1 ,000 to about 8,000, about 2,000 to about 5,000, or about 3,000 to about 4,500.

[0029] The centrifuging of the aqueous phase may occur for an effective period, which may depend on one or more factors, such as incoming volume, type of centrifuge, operating parameters of the centrifuge, etc. The centrifuging of the aqueous phase may occur for a period of about 10 seconds to about 500 seconds, about 10 seconds to about 400 seconds, about 10 seconds to about 300 seconds, about 10 seconds to about 200 seconds, 10 about 10 seconds to about 120 seconds, about 20 seconds to about 100 seconds, or about 30 seconds to about 60 seconds.

[0030] Phase Disengagement Agents and Crud Reducing Agents

[0031] The phase disengagement agents and crud reducing agents may include any compound that is effective to achieve the limitations described herein. In some embodiments, the phase disengagement agent or the crud reducing agent includes a first nonionic surface active agent and a second non-ionic surface active agent.

[0032] In some embodiments, the phase disengagement agent or the crud reducing agent consists of or consists essentially of the first non-ionic surface active agent and the second non-ionic surface active agent, wherein ‘'consisting essentially of’ means no other surface active agents are present that affect phase disengagement time or silica removal. In some embodiments, the phase disengagement agent and the crud reducing agent are the same, and in some embodiments the phase disengagement agent and the crud reducing agent are different in one or more ways, such as a different weight ratio of the first non-ionic surface active agent to the second non-ionic surface active agent.

[0033] The first non-ionic surface active agent may include a polyoxyethylene sorbitan monooleate. In some embodiments, the first non-ionic surface active agent has a weight average molecular weight of about 250 g / mol to about 5000 g / mol, about 500 g / mol to about 5000 g / mol, about 1000 g / mol to about 5000 g / mol, about 1000 g / mol to about 4000 g / mol, about 1000 g / mol to about 3000 g / mol, about 1000 g / mol to about 2000 g / mol, about 1000 g / mol to about 1500 g / mol, about 1100 g / mol to about 1400 g / mol, about 1200 g / mol to about 1400 g / mol, or about 1300 g / mol.

[0034] The second non-ionic surface active agent may include a copolymer, such as a block copolymer, which may be a triblock copolymer. In some embodiments, the second non-ionic surface active agent may include a non-ionic triblock copolymer of polyoxypropylene and polyoxyethylene, a poloxamer. polyethylene glycol, poly(D,L, lactide- co-glycolide. polylactic acid, polyglutamic acid, poly caprolactone, or a combination thereof. The second non-ionic surface active agent may include a polyoxy ethylene-polyoxypropylene block copolymer. In some embodiments, the polyoxyethylene-polyoxypropylene block copolymer has a structure according to the following formula:

[0036] wherein x is 2 to 150, and y is 5 to 100. In some embodiments, x and y are selected from the following table:

[0037] In some embodiments, the second non-ionic surface active agent has a weight average molecular weight of about 500 g / mol to about 6000 g / mol, about 500 g / mol to about 5000 g / mol, about 500 g / mol to about 4000 g / mol, about 1000 g / mol to about 4000 g / mol, about 2000 g / mol to about 4000 g / mol, about 2500 g / mol to about 3500 g / mol. about 2600 g / mol to about 3400 g / mol, about 2700 g / mol to about 3300 g / mol, about 2800 g / mol to about 3200 g / mol, about 2800 g / mol to about 3100 g / mol, about 2800 g / mol to about 3000 g / mol, or about 2900 g / mol.

[0038] The first non-ionic surface active agent and the second non-ionic surface active agent generally may be present at any weight ratio. In some embodiments, the first non-ionic surface active agent and the second non-ionic surface active agent are present in the phase disengagement agent at a weight ratio of from about 5:95 to about 45:55, about 10:90 to about 45:55, about 20:80 to about 45:55, about 25:75 to about 45:55. about 25:75 to about 40:60, or about 30:70 to about 40:60 (first non-ionic surface active agent : second non-ionic surface active agent). In some embodiments, the first non-ionic surface active agent and the second non-ionic surface active agent are present in the phase disengagement agent at a weight ratio of from about 20:80 to about 1 :99, about 20:80 to about 5:95, about 15:85 to about 5:95. or about 10:90 (first non-ionic surface active agent : second non-ionic surface active agent).

[0039] The phase disengagement agent or the crud reducing agent may include one or more additional surface active agents, which may be cationic, anionic, amphoteric, or non- ionic. In some embodiments, the phase disengagement agent or the crud reducing agent also includes polyethylene glycol sorbitan monolaurate.

[0040] The first non-ionic surface active agent and the second non-ionic surface active agent, independently, may have an HLB that is equal to or greater than 10; forexample, about 10 to about 18, about 12 to about 18, about 12 to about 17, about 13 to about 16, or about 14.5 to about 15.5.

[0041] In some embodiments, (i) the phase disengagement agent and / or the crud reducing agent does not include a thiocarbonyl functional group, (ii) the aqueous phase does not include a compound comprising a thiocarbonyl functional group, or (iii) the phase disengagement agent and / or the crud reducing agent does not include a thiocarbonyl functional group, and the aqueous phase does not include a compound comprising a thiocarbonyl functional group.

[0042] Aqueous Phase

[0043] In some embodiments, the aqueous phases provided herein include water. In some embodiments, the aqueous phases provided herein include water and a material to be extracted. In some embodiments, the aqueous phases provided herein include water, a material to be extracted, and silica. The aqueous phase may include one or more suspended solids; therefore, in some instances, the aqueous phase may be referred to as a “slurry’'. As a result, limitations such as “providing an aqueous phase” and “contacting the aqueous phase and a crud reducing agent” read on providing a slurry and contacting the slurry and a crud reducing agent. An aqueous phase also may include an acid, such as sulfuric acid.

[0044] The water of the aqueous phases provided herein may include deionized water. The water may be present in the aqueous phases at any effective amount. Typically, water is present in an aqueous phase at a concentration and / or amount that is greater than the concentration and / or amount of each of the other components that may be present in the aqueous phase. In some embodiments, the water is present in an aqueous phase at an amount of about 40 % to about 99.999 %, about 50 % to about 99.999 %, about 60 % to about 99.999 %, about 75 % to about 99.999 %, about 80 % to about 99.999 %, about 85 % to about 99.999 %, about 90 % to about 99.999 %, about 95 % to about 99.999 %, about 98 % to about 99.999 %, or about 99 % to about 99.999 %, by weight.

[0045] Silica may be present at any amount. In some embodiments, silica is present in the aqueous phase (e.g., prior to contacting an aqueous phase and a crud reducing agent) at an amount of about 0.5 g / L to about 3 g / L, about 0.5 g / L to about 2 g / L, or about 0.5 g / L to about 1.5 g / L. The silica may present, at least initially (e.g., prior to contact an aqueous phase and a crud reducing agent), in the aqueous phase in the form of particles having a first average particle size, as measured by dynamic light scattering.

[0046] An aqueous phase may have an acidic pH. In some embodiments, the aqueous phase has a pH that is less than or equal to 3, less than or equal to 2.5, or about 2. Duringand / or after the preparation of an aqueous phase, a pH of an aqueous phase may be modified, such as by reducing the pH.

[0047] The “material to be extracted” may include an element and / or compound that is extractable with the methods provided herein. In some embodiments, the material to be extracted includes one or more metals. The one or more metals may include one or more rare earth metals, one or more precious metals, or a combination thereof. The one or more metals may include copper, iron, uranium, nickel, cobalt, vanadium, molybdenum, germanium, palladium, or a combination thereof. In some embodiments, the metal is copper. The one or more metals may be present in the form of one or more metal-containing compounds, such as one or more metal oxides, one or more metal sulfides, one or more metal salts, such as CuSO4, FeS04, MnSO4, CoSO4. or a combination thereof. Each material to be extracted, such as each of the one or more metals (for example, copper), may be present in the aqueous phase (before the aqueous phase and an organic phase are contacted) at an amount of about 1 g / L to about 20 g / L, about 1 g / L to about 15 g / L, about 1 g / L to about 10 g / L, about 2 g / L to about 8 g / L, or about 3 g / L to about 6 g / L.

[0048] Organic Phase

[0049] In some embodiments, the organic phases provided herein include an organic liquid. In some embodiments, the organic phases provided herein include an organic liquid and an extraction reagent. Typically, an organic liquid is present in an organic phase at a concentration and / or amount that is greater than the concentration and / or amount of each of the other components that may be present in the organic phase.

[0050] As used herein, the phrase “organic liquid” refers to a compound that (i) is in the liquid phase at 20 °C and 1 atmosphere, (ii) has no or limited (i.e., < 10 mg / L) solubility in water, and (iii) has a chemical formula featuring carbon and hydrogen, wherein carbon and hydrogen, in total, constitute at least 70 %, at least 80 %, at least 90 %, at least 95 %, or 100 % of the molecular weight of the compound. Non-limiting examples of organic liquids include alkanes, alkenes, and alkynes, each of which may be linear, branched, cyclic (e.g., aromatic), or a combination thereof. In some embodiments, the organic liquid includes an oil. such as kerosene, diesel, or other fuel oil.

[0051] In some embodiments, the organic liquid is present in the organic phase at an amount of about 75 % to about 100 %, about 75 % to about 98 %, about 80 % to about 95 %, or about 85 % to about 95 %, by volume.

[0052] Generally, any extraction reagent known in the art may be included in an organic phase, including those that are commercially available. In some embodiments, theextraction reagent includes an aromatic moiety. In some embodiments, the extraction reagent includes an aromatic substituted oxime. An extraction reagent may be present at any effective amount. In some embodiments, the extraction reagent is present in the organic phase at an amount of about 2 % to about 30 %, about 2 % to about 25 %, about 2 % to about 20 %, about 5 % to about 20 %, or about 5 % to about 15 %, by volume.

[0053] EMBODIMENTS

[0054] The following is a non-limiting list of embodiments.

[0055] Embodiment 1. A method of solvent extraction, the method comprising:

[0056] (A) providing an aqueous phase; contacting the aqueous phase and an organic phase to form a mixture; contacting (i) the aqueous phase, the organic phase, or the mixture and (ii) a phase disengagement agent; or

[0057] (B) providing an aqueous phase comprising water and a material to be extracted; contacting the aqueous phase and an organic phase to form a mixture, wherein the organic phase comprises an organic liquid and optionally an extraction reagent; contacting (i) the aqueous phase, the organic phase, or the mixture and (ii) a phase disengagement agent; or

[0058] (C) providing an aqueous phase comprising water, a material to be extracted, and silica; contacting the aqueous phase and an organic phase to form a mixture, wherein the organic phase comprises an organic liquid and optionally an extraction reagent; contacting (i) the aqueous phase, the organic phase, or the mixture and (ii) a phase disengagement agent; and separating the aqueous phase and the organic phase; or

[0059] (D) providing an aqueous phase comprising water, a material to be extracted, and a first amount of silica; contacting the aqueous phase and a crud reducing agent; removing at least a portion of the first amount of silica from the aqueous phase to form a treated aqueous phase comprising a second amount of silica, wherein the removing of at least a portion of the first amount of silica from the aqueous phase comprises an active technique, such as centrifugation, a passive technique, or a combination thereof; contacting the treated aqueous phase and an organic phase, wherein the organic phase comprises an organic liquid and optionally an extraction reagent; contacting the treated aqueous phase and a phase disengagement agent (i) before the contacting of the treated aqueous phase and the organic phase, or (ii) after the contacting of the treated aqueous phase and the organic phase; and separating the treated aqueous phase and the organic phase.

[0060] Embodiment 2. The method of Embodiment 1, wherein the separating of the aqueous phase (or treated aqueous phase) and the organic phase is completed at a phasedisengagement time that is at least 2 %, at least 3 %, at least 4 %, at least 5 %, at least 10 %, at least 15 %, at least 20 %, at least 25 %, at least 30 %. at least 35 %, at least 40 %, at least 45 %, at least 50 %, at least 60 %, at least 70 %, at least 80 %, at least 90 %, about 2 % to about 90 %, about 2 % to about 80 %, about 2 % to about 70 %, about 2 % to about 60 %, about 2 % to about 50 %, about 2 % to about 45 %, about 2 % to about 40 %, about 2 % to about 35 %, about 2 % to about 30 %, about 2 % to about 25 %, about 2 % to about 20 %, about 2 % to about 15 %, about 2 % to about 10 %, about 2 % to about 5 %, about 2 % to about 4 %, about 5 % to about 10 %, about 40 % to about 90 %, or about 40 % to about 80 % less than a time to separate the aqueous phase (or treated aqueous phase) and the organic phase in the absence of the phase disengagement agent, or in the presence of a comparable phase disengagement agent.

[0061] Embodiment 3. The method of any of the preceding embodiments, wherein the contacting of the aqueous phase (or treated aqueous phase) and the organic phase comprises mixing the aqueous phase (or treated aqueous phase) and organic phase.

[0062] Embodiment 4. The method of Embodiment 3, wherein the mixing occurs for a mixing time, which may be a predetermined mixing time, and the contacting of the aqueous phase (or treated aqueous phase) and the phase disengagement agent occurs before the mixing time commences, or before the mixing times ends, such as after at least 25 %, at least 50 %, at least 60 %, at least 70 %, at least 80 %. or at least 90 %, or after 100 % of the mixing time has transpired.

[0063] Embodiment 5. The method of any of Embodiments 1 to 3, further comprising subjecting the aqueous phase (or treated aqueous phase) to leaching prior to the contacting of the aqueous phase (or treated aqueous phase) and the organic phase, wherein the aqueous phase (or treated aqueous phase) and the phase disengagement agent are contacted after the leaching and before the contacting of the aqueous phase (or treated aqueous phase) and the organic phase.

[0064] Embodiment 6. The method of any of the preceding embodiments, wherein the phase disengagement agent comprises, consists of, or consists essentially of a first and a second surface active agent, as described herein, and, optionally, at least one additional surface active agent.

[0065] Embodiment 7. The method of any of the preceding embodiments, wherein (i) the phase disengagement agent does not include a thiocarbonyl functional group, (ii) the aqueous phase does not include a compound comprising a thiocarbonyl functional group, or(iii) the phase disengagement agent does not include a thiocarbonyl functional group, and the aqueous phase does not include a compound comprising a thiocarbonyl functional group.

[0066] Embodiment 8. The method of any of the preceding embodiments, (i) wherein the phase disengagement agent is present at an amount, relative to the aqueous phase (or treated aqueous phase), the organic phase, or the mixture of about 0. 1 ppm to about 400 ppm, about 0. 1 ppm to about 300 ppm, about 0. 1 ppm to about 250 ppm, about 0.1 ppm to about 200 ppm. about 0. 1 ppm to about 100 ppm, about 0. 1 ppm to about 50 ppm, about 0. 1 ppm to about 30 ppm, 1 ppm to about 30 ppm, about 5 ppm to about 30 ppm, about 5 ppm to about 25 ppm, about 5 ppm to about 20 ppm, about 5 ppm to about 15 ppm, about 5 ppm to about 10 ppm, about 10 ppm to about 30 ppm, about 15 ppm to about 30 ppm, about 20 ppm to about 30 ppm. about 25 ppm to about 30 ppm, about 1 ppm to about 20 ppm, or about 1 ppm to about 10 ppm; or (ii) wherein the phase disengagement agent is present at an amount, relative to the aqueous phase (or treated aqueous phase), of about 5 ppm to about 1,000 ppm, 100 ppm to about 1,000 ppm, about 100 ppm to about 700 ppm, about 100 ppm to about 600 ppm, about 200 ppm to about 600 ppm, about 300 ppm to about 600 ppm, about 100 ppm to about 500 ppm, about 100 ppm to about 400 ppm. or about 100 ppm to about 300 ppm.

[0067] Embodiment 9. A method of solvent extraction, the method comprising providing an aqueous phase comprising water, a material to be extracted, and a first amount of silica; contacting the aqueous phase and a crud reducing agent; and removing at least a portion of the first amount of silica from the aqueous phase to form a treated aqueous phase comprising a second amount of silica, wherein the removing of at least a portion of the first amount of silica from the aqueous phase comprises an active technique, such as centrifugation, a passive technique, or a combination thereof.

[0068] Embodiment 10. The method of Embodiment 1 or 9, wherein the second amount of silica is at least 2 %, at least 5 %, at least 10 %, at least 15 %, at least 20 %, at least 25 %, at least 30 %, at least 35 %, at least 40 %, at least 45 %, at least 50 %, at least 60 %, at least 70 %, at least 80 %, at least 85 %, at least 90 %, at least 95 %, or at least 99 % less than the first amount of silica.

[0069] Embodiment 11. The method of Embodiment of 1, 9 or 10, further comprising contacting the treated aqueous phase and an organic phase, wherein the organic phase comprises an organic liquid and optionally an extraction reagent; and separating the treated aqueous phase and the organic phase.

[0070] Embodiment 12. The method of Embodiment 11 , wherein the contacting of the treated aqueous phase and the organic phase comprises mixing the treated aqueous phase and organic phase.

[0071] Embodiment 13. The method of any one of Embodiments 1 or 9 to 12, wherein the removing of the at least a portion of the first amount of silica from the aqueous phase comprises centrifuging and decanting the aqueous phase.

[0072] Embodiment 14. The method of any one of Embodiments 1 or 9 to 13, wherein (i) the crud reducing agent does not include a thiocarbonyl functional group, or (ii) the aqueous phase does not include a compound comprising a thiocarbonyl functional group.

[0073] Embodiment 15. The method of any one of Embodiments 1 or 9 to 14, wherein the crud reducing agent does not include a thiocarbonyl functional group, and the aqueous phase does not include a compound comprising a thiocarbonyl functional group.

[0074] Embodiment 16. The method of any one of Embodiments! or 9 to 15, wherein after the contacting of the aqueous phase and the crud reducing agent, the crud reducing agent is present in the aqueous phase at an amount (i) that is less than or equivalent to the critical micelle concentration (CMC) of a crud reducing agent, or (ii) of about 0. 1 ppm to about 200 ppm, about 0. 1 ppm to about 180 ppm, about 0. 1 ppm to about 160 ppm, about 0.1 ppm to about 140 ppm, about 0. 1 ppm to about 120 ppm, about 0.1 ppm to about 100 ppm, about 10 ppm to about 100 ppm, about 30 ppm to about 100 ppm, about 0. 1 ppm to about 80 ppm, about 0. 1 ppm to about 60 ppm, about 0. 1 ppm to about 40 ppm, about 0. 1 ppm to about 30 ppm, about 0. 1 ppm to about 25 ppm, about 0.1 ppm to about 20 ppm, about 0. 1 ppm to about 15 ppm, about 0.1 ppm to about 12 ppm, about 1 ppm to about 10 ppm, about 2 ppm to about 10 ppm, about 3 ppm to about 10 ppm, about 4 ppm to about 10 ppm, about 5 ppm to about10 ppm, about 6 ppm to about 10 ppm, about 7 ppm to about 10 ppm, about 8 ppm to about10 ppm, about 9 ppm to about 10 ppm, about 2 ppm to about 8 ppm, about 3 ppm to about 7 ppm, or about 4 ppm to about 6 ppm.

[0075] Embodiment 17. The method of any one of Embodiments 1 or 9 to 16, wherein the centrifuging of the aqueous phase comprises subjecting the aqueous phase to a gravitational force equivalent (g-force) up to 20,000, up to 15,000, or up to 10.000; for example, about 10 to about 8,000, about 100 to about 8,000, about 1,000 to about 8,000, about 2,000 to about 5,000, or about 3,000 to about 4,500.

[0076] Embodiment 18. The method of any one of Embodiments 1 or 9 to 17, wherein the centrifuging of the aqueous phase occurs for an effective period, which maydepend on one or more factors, such as incoming volume, type of centrifuge, operating parameters of the centrifuge, etc.

[0077] Embodiment 19. The method of any of the preceding embodiments, wherein the water is present in the aqueous phase (or treated aqueous phase) at a concentration and / or amount that is greater than the concentration and / or amount of each of the other components that may be present in the aqueous phase (or treated aqueous phase).

[0078] Embodiment 20. The method of any of the preceding embodiments, wherein the water is present in the aqueous phase at an amount of about 40 % to about 99.999 %, about 50 % to about 99.999 %, about 60 % to about 99.999 %, about 75 % to about 99.999 %, about 80 % to about 99.999 %, about 85 % to about 99.999 %, about 90 % to about 99.999 %, about 95 % to about 99.999 %. about 98 % to about 99.999 %, or about 99 % to about 99.999 %, by weight.

[0079] Embodiment 21. The method of any of the preceding embodiments, wherein the aqueous phase (or treated aqueous phase) has a pH that is less than or equal to 3, less than or equal to 2.5. or about 2.

[0080] Embodiment 22. The method of any of the preceding embodiments, wherein the material to be extracted comprises one or more metals.

[0081] Embodiment 23. The method of any of the preceding embodiments, wherein the one or more metals comprise (i) one or more rare earth metals, one or more precious metals, or a combination thereof; (ii) copper, iron, uranium, nickel, cobalt, vanadium, molybdenum, germanium, palladium, or a combination thereof; or (iii) copper.

[0082] Embodiment 24. The method of any of the preceding embodiments, wherein the one or more metals are present in the form of one or more metal-containing compounds, such as one or more metal oxides, one or more metal sulfides, one or more metal salts, such as CuSCL, FeSCL, MnSCh, CoSO4, or a combination thereof.

[0083] Embodiment 25. The method of any of the preceding embodiments, wherein each of the one or more metals is present in the aqueous phase (before the aqueous phase (or treated aqueous phase) and an organic phase are contacted) at an amount of about 1 g / L to about 20 g / L, about 1 g / L to about 15 g / L. about 1 g / L to about 10 g / L. about 2 g / L to about 8 g / L, or about 3 g / L to about 6 g / L.

[0084] Embodiment 26. The method of any of the preceding embodiments, wherein (i) the silica is present in the aqueous phase at an amount of about 0.5 g / L to about 3 g / L, about 0.5 g / L to about 2 g / L. or about 0.5 g / L to about 1.5 g / L, or (ii) the first amount ofsilica in the aqueous phase is about 0.5 g / L to about 3 g / L, about 0.5 g / L to about 2 g / L, about 0.5 g / L to about 1.5 g / L.

[0085] Embodiment 27. The method of any of the preceding embodiments, wherein (i) the silica is present in the aqueous phase in the form of particles, or (ii) the first amount of silica is present in the aqueous phase in the form of particles having a first average particle size, as measured by dynamic light scattering.

[0086] Embodiment 28. The method of any of the preceding embodiments, wherein, after the contacting of the aqueous phase and the crud reducing agent (e.g., at least 5 seconds, at least 10 seconds, or at least 20 seconds after the contacting of the aqueous phase and the crud reducing agent), the first amount of silica is present in the aqueous phase in the form of particles having a second average particle size, as measured by dynamic light scattering, wherein the second average particle size is at least 2 times, at least 3 times, at least 4 times, at least 5 times, or at least 10 times greater than the first average particle size of Embodiment 27.

[0087] Embodiment 29. The method of any of the preceding embodiments, wherein the phase disengagement agent or the crud reducing agent comprises, consists essentially of. or consists of a first non-ionic surface active agent and a second non-ionic surface active agent.

[0088] Embodiment 30. The method of Embodiment 29, wherein the first non-ionic surface active agent comprises, consists essentially of, or consists of (A) a sorbitol based surface active agent, (B) a sorbitol based ethoxylated surface active agent, or (C) a polyoxyethylene sorbitan monooleate, polyoxyetheylene lauryl ether, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan monopalmitate, or a combination thereof.

[0089] Embodiment 31. The method of Embodiment 29 or 30, wherein the second non-ionic surface active agent comprises, consists essentially of, or consists of (A) a polymer, (B) a copolymer, such as a block copolymer, which may be a triblock copolymer, (C) a polyoxy ethylene-polyoxypropylene block copolymer, or (D) non ionic triblock copolymers of polyoxypropyelne and polyoxyethylene, poloxamers, polyethylene glycol, poly (D,L, lactide- co-glycolide. polylactic acid, polyglutamic acid, poly caprolactone, or a combination thereof.

[0090] Embodiment 32. The method of any one of Embodiments 29 to 31 , wherein the first non-ionic surface active agent and the second non-ionic surface active agent are present in the phase disengagement agent at a weight ratio of from about 5:95 to about 45:55, about 10:90 to about 45:55, about 20:80 to about 45:55. about 25:75 to about 45:55, about 25:75 to about 40:60, about 30:70 to about 40:60, about 20:80 to about 1 :99, about 20:80 toabout 5:95, about 15:85 to about 5:95, or about 10:90 (first non-ionic surface active agent : second non-ionic surface active agent).

[0091] Embodiment 33. The method of any one of Embodiments 29 to 32, wherein the first non-ionic surfactant comprises, consists essentially of, or consists of a polyoxyethylene sorbitan monooleate.

[0092] Embodiment 34. The method of any one of Embodiments 29 to 33, wherein the phase disengagement agent or the crud reducing agent further comprises, consists essentially of, or consists of polyethylene glycol sorbitan monolaurate.

[0093] Embodiment 35. The method of any one of Embodiments 29 to 34, wherein the polyethylene glycol polypropylene glycol block copolymer has a structure according to the following formula:

[0095] wherein x is 2 to 150, and y is 5 to 100.

[0096] Embodiment 36. The method of Embodiment 35, wherein x and y are selected from the following table:

[0097] Embodiment 37. The method of any one of Embodiments 29 to 36, wherein the first non-ionic surface active agent and the second non-ionic surface active agent, independently, have an HLB that is equal to or greater than 10; for example, about 10 to about 18, about 12 to about 18, about 12 to about 17, about 13 to about 16, or about 14.5 to about 15.5.

[0098] Embodiment 38. The method of any one of Embodiments 29 to 37, wherein the first non-ionic surface active agent has a weight average molecular weight of about 250 g / mol to about 5000 g / mol, about 500 g / mol to about 5000 g / mol, about 1000 g / mol to about 5000 g / mol, about 1000 g / mol to about 4000 g / mol, about 1000 g / mol to about 3000 g / mol, about 1000 g / mol to about 2000 g / mol, about 1000 g / mol to about 1500 g / mol, about 1100 g / mol to about 1400 g / mol, about 1200 g / mol to about 1400 g / mol, or about 1300 g / mol; and wherein the second non-ionic surface active agent has a weight average molecular weight of about 500 g / mol to about 6000 g / mol, about 500 g / mol to about 5000 g / mol, about 500 g / mol to about 4000 g / mol, about 1000 g / mol to about 4000 g / mol, about 2000 g / mol to about 4000 g / mol, about 2500 g / mol to about 3500 g / mol. about 2600 g / mol to about 3400 g / mol, about 2700 g / mol to about 3300 g / mol, about 2800 g / mol to about 3200 g / mol. about 2800 g / mol to about 3100 g / mol, about 2800 g / mol to about 3000 g / mol, or about 2900 g / mol.

[0099] Embodiment 39. The method of any one of the preceding embodiments, wherein the first non-ionic surface active agent and the second non-ionic surface active agent, independently, have a weight average molecular weight (Mw) of about 0.2 kDa to about 100 kDa, about 0.5 kDa to about 100 kDa, about 0.2 kDa to about 80 kDa, about 0.2 kDa to about 60 kDa, about 0.2 kDato about 40 kDa, about 0.2 kDa to about 20 kDa, about 0.2 kDa to about 10 kDa, about 0.2 kDa to about 5 kDa, about 0.2 kDa to about 2 kDa, about 1 kDa to about 2 kDa, about 1 kDa to about 1.5 kDa, or about 1.2 kDa to about 1.4 kDa.

[0100] Embodiment 40. The method of any of the preceding embodiments, wherein the organic liquid is present in the organic phase at an amount of about 75 % to about 100 %, about 75 % to about 98 %, about 80 % to about 95 %, or about 85 % to about 95 %, byvolume.

[0101] Embodiment 41. The method of any of the preceding embodiments, wherein the extraction reagent is present in the organic phase at an amount of about 2 % to about 30 %, about 2 % to about 25 %, about 2 % to about 20 %, about 5 % to about 20 %, or about 5 % to about 15 %. by volume.

[0102] Embodiment 42. The method of any of the preceding embodiments, wherein the organic liquid comprises an alkane, an alkene, an alkyne, or combination thereof, each of which may be linear, branched, cyclic, or a combination thereof.

[0103] Embodiment 43. The method of any of the preceding embodiments, wherein the organic liquid includes an oil, such as kerosene, diesel, or other fuel oil.

[0104] Embodiment 44. The method of any of the preceding embodiments, wherein the method is performed with aqueous continuity or organic continuity.

[0105] Embodiment 45. A composition comprising, consisting essentially of, or consisting of the phase disengagement agent or the crud reducing agent of any of the preceding embodiments.

[0106] All referenced publications are incorporated herein by reference in their entirety. Furthermore, where a definition or use of a term in a reference, which is incorporated by reference herein, is inconsistent or contrary to the definition of that term provided herein, the definition of that term provided herein applies and the definition of that term in the reference does not apply.

[0107] While certain aspects of conventional technologies have been discussed to facilitate disclosure of various embodiments, applicants in no way disclaim these technical aspects, and it is contemplated that the present disclosure may encompass one or more of the conventional technical aspects discussed herein.

[0108] The present disclosure may address one or more of the problems and deficiencies of know n methods and processes. However, it is contemplated that various embodiments may prove useful in addressing other problems and deficiencies in a number of technical areas. Therefore, the present disclosure should not necessarily be construed as limited to addressing any of the particular problems or deficiencies discussed herein.

[0109] In this specification, where a document, act or item of know ledge is referred to or discussed, this reference or discussion is not an admission that the document, act or item of knowledge or any combination thereof was at the priority date, publicly available, known to the public, part of common general knowledge, or otherwise constitutes prior art under the applicable statutory provisions; or is known to be relevant to an attempt to solve any problem with which this specification is concerned.

[0110] In the descriptions provided herein, the terms “includes,” “is,” “containing,” “having,” and “comprises” are used in an open-ended fashion, and thus should be interpreted to mean “including, but not limited to.” When methods are claimed or described in terms of“comprising"’ various steps or components, the methods can also “consist essentially of’ or “consist of’ the various steps or components, unless stated otherwise.

[0111] The terms “a,” “an,” and "‘the” are intended to include plural alternatives, e.g., at least one. For instance, the disclosure of “a surface active agent”, “an organic liquid”, and the like, is meant to encompass one, or mixtures or combinations of more than one surface active agent, organic liquid, and the like, unless otherwise specified.

[0112] Various numerical ranges may be disclosed herein. When Applicant discloses or claims a range of any type, Applicant’s intent is to disclose or claim individually each possible number that such a range could reasonably encompass, including end points of the range as well as any sub-ranges and combinations of sub-ranges encompassed therein, unless otherwise specified. Moreover, all numerical end points of ranges disclosed herein are approximate. As a representative example, Applicant discloses, in some embodiments, that the extraction reagent is present in the organic phase at an amount of about 5 % to about 15 %, by volume. This range should be interpreted as encompassing about 5 % and about 15 %, and further encompasses "‘about” each of 6 %, 7 %, 8 %, 9 %, 10 %, 11 %, 12 %, 13 %, and 14 %. including any ranges and sub-ranges between any of these values.

[0113] As used herein, the term “about” means plus or minus 10 % of the numerical value of the number with which it is being used.

[0114] EXAMPLES

[0115] The present invention is further illustrated by the following examples, which are not to be construed in any way as imposing limitations upon the scope thereof. On the contrary', it is to be clearly understood that resort may be had to various other aspects, embodiments, modifications, and equivalents thereof which, after reading the description herein, may suggest themselves to one of ordinary7skill in the art without departing from the spirit of the present invention or the scope of the appended claims. Thus, other aspects of this invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein.

[0116] Example 1 - Testing of Phase Disengagement Time

[0117] The organic phase of this example included kerosene and an extractant at the concentration shown in the following table, but other concentrations are envisioned, as described herein.

[0118] The aqueous phase of this example included the components shown at the following table, and the pH of the aqueous phase was adjusted to about 2 with H2SO4 (about 2 rnL to 2 L).

[0119] In this example, the following testing procedure was used.

[0120] Organic continuity: the extraction aqueous phase was added on top of the organic phase, while mixing at about 1750 rpm with a polypropylene impeller. The solution ratio was 1: 1 by volume (for example. 100 mL : 100 mL). Specifically, 100 mL of the foregoing organic phase was added to a 300 mL beaker, and, while mixing, 100 rnL of the foregoing aqueous phase was added to the beaker. Mixing was continued for 3 minutes.

[0121] Prior to stopping mixing, a phase disengagement agent was added. The phrase separation time was then recorded.

[0122] In this example, a series of tests was performed using different concentrations (5 ppm, 10 ppm, and 30 ppm) of a phase disengagement agent that included a polyoxyethylene sorbitan monooleate, and a polyoxyethylene-polyoxypropylene block copolymer at 6 different weight ratios: and one test was a “Reference” test that did not include a phase disengagement agent in the mixture. The results of these tests are provided in the following table (PDT - Phase Disengagement Time).

[0123] The data of this table demonstrated that the phase disengagement agents that included a polyoxyethylene sorbitan monooleate, and a poly oxy ethylene-poly oxypropylene block copolymer reduced the phase disengagement times by a surprising and unexpected extent compared to the “Reference” phase disengagement agent. It also should be noted that the “Reference” test, as shown in the foregoing table, was repeated 3 times to ensure reproducibility of the results.

Claims

Claims:

1. A method of solvent extraction, the method comprising: providing an aqueous phase comprising water and a material to be extracted; contacting the aqueous phase and an organic phase to form a mixture, wherein the organic phase comprises an organic liquid and optionally an extraction reagent; contacting (i) the aqueous phase, the organic phase, or the mixture, and (ii) a phase disengagement agent; and separating the aqueous phase and the organic phase; wherein the separating of the aqueous phase and the organic phase is completed at a phase disengagement time that is at least 2 % less than a time to separate the aqueous phase and the organic phase in the absence of the phase disengagement agent, wherein the phase disengagement agent comprises a first non-ionic surface active agent and a second non-ionic surface active agent, wherein the first non-ionic surface active agent comprises a sorbitol based surface active agent, wherein the second non-ionic surface active agent comprises a copolymer, and wherein the first non-ionic surface active agent and the second non-ionic surface active agent are present in the phase disengagement agent at a weight ratio of from about 10:90 to about 45:55 (first non-ionic surface active agent : second non- ionic surface active agent).

2. The method of claim 1, wherein the contacting of the aqueous phase and the organic phase comprises mixing the aqueous phase and organic phase for a mixing time; and wherein the contacting of the phase disengagement agent and the organic phase, the aqueous phase, or the mixture occurs before the mixing time commences, or before the mixing time ends.

3. The method of claim 1, further comprising leaching the aqueous phase prior to the contacting of the aqueous phase and the organic phase, wherein the aqueous phase and the phase disengagement agent are contacted after the leaching and before the contacting of the aqueous phase and the organic phase.

4. The method of claim 1 , wherein the aqueous phase does not include a compound comprising a thiocarbonyl functional group.

5. The method of claim 1, wherein the separating of the aqueous phase and the organic phase is completed at a phase disengagement time that is at least 10 % less than a time to separate the aqueous phase and the organic phase in the absence of the phase disengagement agent6. The method of claim 1, wherein the phase disengagement agent is present at an amount of about 1 ppm to about 400 ppm, relative to the mixture.

7. The method of claim 1, wherein the first non-ionic surface active agent has a weight average molecular weight of about 250 g / mol to about 5000 g / mol, and wherein the second non-ionic surface active agent has a weight average molecular weight of about 250 g / mol to about 5000 g / mol.

8. The method of claim 1, wherein the copolymer comprises a polyethylene glycol polypropylene glycol block copolymer.

9. A method of solvent extraction, the method comprising: providing an aqueous phase comprising water, a material to be extracted, and a first amount of silica; contacting the aqueous phase and a crud reducing agent; and removing at least a portion of the first amount of silica from the aqueous phase to form a treated aqueous phase comprising a second amount of silica; wherein the second amount of silica is at least 20 % less than the first amount of silica, wherein the crud reducing agent comprises a first non-ionic surface active agent and a second non-ionic surface active agent. wherein the first non-ionic surface active agent comprises a sorbitol based surface active agent, wherein the second non-ionic surface active agent comprises a copolymer, and wherein the first non-ionic surface active agent and the second non-ionic surface active agent are present in the crud reducing agent at a weight ratio of fromabout 10:90 to about 45:55 (first non-ionic surface active agent : second non-ionic surface active agent).

10. The method of claim 9, further comprising: contacting the treated aqueous phase and an organic phase, wherein the organic phase comprises an organic liquid and optionally an extraction reagent: and separating the treated aqueous phase and the organic phase.

11. The method of claim 9, wherein the aqueous phase does not include a compound comprising a thiocarbonyl functional group.

12. The method of claim 9, wherein after the contacting of the aqueous phase and the crud reducing agent, the crud reducing agent is present in the aqueous phase at an amount of about 0. 1 ppm to about 400 ppm.

13. The method of claim 9, wherein the removing of the at least a portion of the first amount of silica comprises (i) disposing the aqueous phase in a thickener or settler, or (ii) centrifuging the aqueous phase, wherein the centrifuging comprises subjecting the aqueous phase to a gravitational force equivalent (g-force) up to 20,000.

14. The method of claim 9, wherein the first non-ionic surface active agent has a weight average molecular weight of about 250 g / mol to about 5000 g / mol, and wherein the second non-ionic surface active agent has a weight average molecular weight of about 500 g / mol to about 5000 g / mol.

15. The method of claim 9, wherein the copolymer comprises a polyethylene glycol polypropylene glycol block copolymer.