Abstract: Embodiments of the present disclosure are directed to systems and methods of removing carbon dioxide from a gaseous stream using magnesium hydroxide and then regenerating the magnesium hydroxide. In some embodiments, the systems and methods can further comprise using the waste heat from one or more gas streams to provide some or all of the heat needed to drive the reactions. In some embodiments, magnesium chloride is primarily in the form of magnesium chloride dihydrate and is fed to a decomposition reactor to generate magnesium hydroxychloride, which is in turn fed to a second decomposition reactor to generate magnesium hydroxide.

Abstract: A printed energy storage device includes a first electrode, a second electrode, and a separator between the first and the second electrode. At least one of the first electrode, the second electrode, and the separator includes frustules, for example of diatoms. The frustules may have a uniform or substantially uniform property or attribute such as shape, dimension, and/or porosity. A property or attribute of the frustules can also be modified by applying or forming a surface modifying structure and/or material to a surface of the frustules. A membrane for an energy storage device includes frustules. An ink for a printed film includes frustules.

Abstract: One solid preparation of the present invention mainly includes silicon fine particles, and has a capability of generating hydrogen. In addition, one specific example of the solid preparation mainly includes silicon fine particles having a crystallite diameter principally of 1 nm or more and 100 nm or less, and exhibits a capability of generating hydrogen in an amount of 3 ml/g or more when brought into contact with a water-containing liquid having a pH value of 7 or more. In this solid preparation, hydrogen is generated when the silicon fine particles are brought into contact with a water-containing liquid having a pH value of 7 or more. Therefore, taking advantage of the characteristics of the solid preparation, generation of hydrogen is promoted in, for example, a gastrointestinal tract where the pH value is 7 or more due to secretion of pancreatic fluid after passage through the stomach after oral ingestion.

Abstract: The present invention relates to a process for the synthesis of a composite material comprising steps of: (a) reacting gaseous magnesium (Mg) and silica (SiO2) in an inert atmosphere; (b) washing the product obtained in step (a) in an acidic medium; and (c) reacting further gaseous magnesium (Mg) with the silica (SiO2) and silicon (Si) product obtained in step (b). The process of the invention allows Mg2Si/MgO nanocomposites to be prepared without too many separate steps, and wherein the MgO phase is homogeneously dispersed within the Mg2Si matrix. The nanocomposites obtained may for example find practical application as thermoelectric materials in thermoelectric generators.

Abstract: Controlling aerosol production during absorption in ammonia-based desulfurization. The absorption reaction temperature, the oxygen content and water content of the process gas may be controlled, and an absorption circulating liquid containing ammonium sulfite may be used for removing sulfur dioxide in flue gas, so as to control aerosol production during absorption in the ammonia-based desulfurization.

Abstract: The present application pertains to methods for making metal oxides and/or citric acid. In one embodiment, the application pertains to a process for producing calcium oxide, magnesium oxide, or both from a material comprising calcium and magnesium. The process may include reacting a material comprising calcium carbonate and magnesium carbonate. Separating, concentrating, and calcining may lead to the production of oxides such as calcium oxide or magnesium oxide. In other embodiments the application pertains to methods for producing an alkaline-earth oxide and a carboxylic acid from an alkaline earth cation-carboxylic acid anion salt. Such processes may include, for example, reacting an alkaline-earth cation-carboxylic acid anion salt with aqueous sulfur dioxide to produce aqueous alkaline-earth-bisulfite and aqueous carboxylic acid solution. Other useful steps may include desorbing, separating, and/or calcining.

Abstract: A printed energy storage device includes a first electrode, a second electrode, and a separator between the first and the second electrode. At least one of the first electrode, the second electrode, and the separator includes frustules, for example of diatoms. The frustules may have a uniform or substantially uniform property or attribute such as shape, dimension, and/or porosity. A property or attribute of the frustules can also be modified by applying or forming a surface modifying structure and/or material to a surface of the frustules. A membrane for an energy storage device includes frustules. An ink for a printed film includes frustules.

Abstract: A process for the calcination of a zeolitic material, wherein the process contains the steps of (i) providing a zeolitic material containing YO2 and optionally further containing X2O3 in its framework structure in the form of a powder and/or of a suspension of the zeolitic material in a liquid, wherein Y stands for a tetravalent element and X stands for a trivalent element; (ii) atomization of the powder and/or of the suspension of the zeolitic material provided in (i) in a gas stream for obtaining an aerosol; and (iii) calcination of the aerosol obtained in (ii) for obtaining a calcined powder, a zeolitic material obtained by the above process, and its use as a molecular sieve, as an adsorbent, for ion-exchange, as a catalyst, and/or as a catalyst support.

Abstract: One solid preparation of the present invention mainly includes silicon fine particles, and has a capability of generating hydrogen. In addition, one specific example of the solid preparation mainly includes silicon fine particles having a crystallite diameter principally of 1 nm or more and 100 nm or less, and exhibits a capability of generating hydrogen in an amount of 3 ml/g or more when brought into contact with a water-containing liquid having a pH value of 7 or more. In this solid preparation, hydrogen is generated when the silicon fine particles are brought into contact with a water-containing liquid having a pH value of 7 or more. Therefore, taking advantage of the characteristics of the solid preparation, generation of hydrogen is promoted in, for example, a gastrointestinal tract where the pH value is 7 or more due to secretion of pancreatic fluid after passage through the stomach after oral ingestion.

Abstract: The present invention provides an alkali metal and/or alkali earth metal extraction method that has excellent extraction efficiency and allows repeated use of an aqueous solution that extracts an alkali metal and/or alkali earth metal from a solid. The alkali metal and/or alkali earth metal extraction method is a method for extracting an alkali metal and/or alkali earth metal from a solid containing the alkali metal and/or alkali earth metal, the method including an elution step in which the solid is added to a neutral amino acid-containing aqueous solution or an amino acid-containing mixed aqueous solution produced by mixing a pH adjusting agent with an aqueous solution containing at least one of a neutral amino acid, an acidic amino acid and a basic amino acid so as to elute the alkali metal and/or alkali earth metal in the neutral amino acid-containing aqueous solution or the amino acid-containing mixed aqueous solution.

Abstract: A manufacturing facility for quicklime is provided, which can manufacture highly active quicklime by a simple manufacturing facility, and which can also separate and recover, in a high concentration, CO2 gas generated at the time of manufacturing quicklime.

Abstract: A thermal protection system (TPS) comprising a mixture of silicon carbide and SiOx that has been converted from Si that is present in a collection of diatom frustules and at least one diatom has quasi-periodic pore-to-pore separation distance d(p-p) in a selected range. Where a heat shield comprising the converted SiC/SiOx frustules receives radiation, associated with atmospheric (re)entry, a portion of this radiation is reflected so that radiation loading of the heat shield is reduced.

Abstract: Single crystals of the new semiconducting oxychalcogenide phase were synthesized using a novel crystal growth method. The crystals had low defects and homogeneous composition as characterized by single crystal X-ray diffraction and scanning electron microscopy, respectively. Heat capacity and resistivity measurements were in agreement with the calculated band structure calculations indicating semiconductivity, with a band gap of about 3 eV.

Abstract: A process for the treatment of a silicate mineral, includes: preparing a first composition including an alkali metal magnesium orthosilicate and optionally either (i) magnesium oxide or (ii) an alkali metal silicate, by reaction, at a temperature from 500 to 1200° C., of an alkali metal carbonate compound, which compound is an alkali metal carbonate, an alkali metal bicarbonate or a mixture thereof, with a magnesium silicate, the molar ratio of alkali metal carbonate compound, expressed as alkali metal oxide of the formula R2O, in which R represents an alkali metal, to magnesium silicate, expressed as silicon dioxide, of the formula SiO2, being from 4:1 to 1:4, and contacting the first composition with water to produce a second composition comprising an amorphous magnesium silicate hydrate (M-S—H).

Abstract: A magnesium oxide powder having excellent dispersibility and a small average particle diameter as well as a uniform particle diameter and containing no very small size particles is obtained. A magnesium oxide powder which is particles, wherein the magnesium oxide powder has a BET specific surface area of 5 m2/g or more, a cumulative 50% particle diameter (D50) obtained in the measurement of laser diffraction scattering particle size distribution of 0.3 to 1.5 ?m, a ratio of a cumulative 90% particle diameter (D90) to a cumulative 10% particle diameter (D10) (D90/D10) obtained in the measurement of laser diffraction scattering particle size distribution of 5 or less, and a D10 of 0.1 ?m or more.

Abstract: The invention relates to CO2 capturing binder with an amortized environmental cost, the method of manufacture thereof by means of selecting, purifying and optimizing the carbide lime paste for use as a cementing material, and aggregates for the manufacture of lime paints and slurries, stuccos, mortars and concretes having multiple applications in the construction industry, in architectural restoration, in public works and land conditioning, object of the present invention. It is basically characterized in that the raw material is the residue in the form of sludge generated in the industrial manufacture of acetylene (C2H2) from calcium carbide (CaC2) the fundamental component of which is calcium hydroxide (Ca(OH)2) in highly reactive nanometric formations treated in a specific manner according to the invention.

Abstract: A process is for extracting natural hydroxyapatite from bone in order to make granules for a bone graft. The process involves soaking and boiling raw bone cubes in deionized water. Soaking and boiling removes lipids, blood components, and proteins and creates bone cubes. Next, washing the bone cubes in deionized water and drying the bone cubes. Then, segregating cancellous bone cubes with densified porous structure from those without densified porous structure. After that, soaking the cancellous bone cubes with densified porous structure in a solution of sodium hydroxide and a solution of hydrogen peroxide. Next, washing the cancellous bone cubes with densified porous structure in deionized water and drying the bone cubes. Then, sintering the cancellous bone cubes with densified porous structure. After that, fracturing the cancellous bone cubes with densified porous structure into the granules for the bone graft.

Abstract: A composite particle and a population of particles comprising a water-insoluble polyphosphate composition, methods of producing, and methods of using the same are provided. The polyphosphate composition may comprise at least one alkaline earth metal selected from calcium and magnesium and optionally at least one nutrient ion selected from the group consisting of potassium, ammonium, zinc, iron, manganese, copper, boron, chlorine, iodine, molybdenum, selenium or sulfur.

Abstract: A method for synthesis of a ferroelectric material characterized by the general formula AxByFz where A is an alkaline earth metal, B is transition metal or a main group metal, x and y each range from about 1 to about 5, and z ranges from about 1 to about 20 comprising contacting an alkaline earth metal fluoride, a difluorometal compound and a fluoroorganic acid in a medium to form a reaction mixture; and subjecting the reaction mixture to conditions suitable for hydrothermal crystal growth.

Abstract: The invention provides a simple an efficient method for the synthesis of CaS nanoparticles, where a solution of CaAc in DMSO is warmed in a microwave oven.

Abstract: The invention relates to non-ferrous metallurgy and can be used for extracting beryllium from genthelvite and bertrandtte groups when processing the raw minerals (ores, concentrates) by heap and vat leaching. The objective of the invention is to disclose a method of teaching beryllium from danalite (Fe8 (BeSiO4) 6S2), genthelvite (Zn8 (BeSiO4) 6S2), helvite (Mg8 (BeSiO4) 6S2), chrysoberyl, euclase, and bertrandite, thus expanding the range of raw minerals used for processing and providing more economical production and improved environmental impact via use of an effective reagent at low temperatures by hydrochemical method. The offered method is beneficial both economically and ecologically, as the alternate modern pyrometallurgical method of beryllium extraction has the following drawbacks: emission of toxic gases, high energy requirements, and the need for fireproof materials.

Abstract: The present invention may provide talc calciner systems and methods to produce better and more efficient products by engineering a* and b* values for calcinated products perhaps by processing low iron talc in an indirectly heated, multiple zoned calciner which may progressively heat the feed supply at perhaps specifics residence times to produce a desired product.

Abstract: The present invention teaches the method to use the sulfate or sulfites based raw materials, such as magnesium, calcium and other alkative earth sulfates or sulfites to produce the respective oxides in a carbon five basis, by using sulfur as the fuel and the reductant. The invention also utilizes renewable energy such as solar thermal or green electricity wherever possible. This approach provides a green process, of ultra-low carbon dioxide emission, for the production of magnesium, other alkaline earth metals and other material which requires alkaline earth oxide, such as in the production of carbon free Portland cement requiring lime. The invention also provides a useful outlet for waste streams leading to sustainable processes. The cost of the production of these precursors are kept low by concurrently producing a saleable by-product—sulfuric-acid.

Abstract: The present invention relates to an economic process for preparing surface-reacted calcium carbonate. The present invention further relates to a surface-reacted calcium carbonate having an increased specific BET surface area, and the use of a process for adjusting the specific BET surface area.

Abstract: A method for recovering base metal values from oxide ore is provided, where the ore includes a first group metal selected from nickel, cobalt and copper. The method includes reducing ore particle size to suit the latter unit operation, favoring contact for the metal elements, contacting the ore with ferric or ferrous chloride, hydrated or anhydrous, to produce a mix of ore and iron (II or III) chloride subjecting the mixture of the ore and ferric or ferrous chloride to enough energy to decompose the chlorides into hydrochloric acid and a iron oxides from the second group, forming their respective chlorides, selectively dissolve the produced base metal chlorides, leaving the metal as oxides and in the solid state, and recovering the dissolved base metal values from aqueous solution.

Abstract: A method for leaching of minerals and sequestration of CO2 is disclosed, wherein the method comprises forming a rock pile; injecting exhaust gas containing CO2 in the lower part of the rock pile; spraying leaching liquid on top of the rock pile; collecting enriched leaching liquid from a lower part of the rock pile; precipitating mineral carbonates from the enriched leaching liquid, or further extracting dissolved elements or compounds.

Abstract: The present invention relates to an economic process for preparing surface-reacted calcium carbonate. The present invention further relates to a surface-reacted calcium carbonate having an increased specific BET surface area, and the use of a process for adjusting the specific BET surface area.

Abstract: This invention relates to treated geothermal brine compositions containing reduced concentrations of silica, iron, and potassium compared to the untreated brines. Exemplary compositions of the treated brine contain a concentration of silica ranging from about 0 mg/kg to about 15 mg/kg, a concentration of iron ranging from about 0 mg/kg to about 10 mg/kg, and a concentration of potassium ranging from about 300 mg/kg to about 8500 mg/kg. Other exemplary compositions of the treated brines also contain reduced concentrations of elements like rubidium, cesium, and lithium.

Abstract: Provided is a recycling method for producing calcite and ammonium sulfate having a high purity of at least 95% and generated by means of a carbonation reaction for fixing carbon dioxide inside the crystal structure of a mineral, and in which waste gypsum is reacted with carbon dioxide, which is a greenhouse gas, such that the carbon dioxide is fixed as a stable mineral, and high-purity calcite and ammonium sulfate are produced as resultant products.

Abstract: An object of the present invention is to provide a method for producing a metal hydroxide fine particle, which can produce metal hydroxide fine particles with favorable crystallinity and small particle sizes. The present invention provides a method for producing a metal hydroxide fine particle by reacting a metal ion with a hydroxide ion in a solvent, which includes a mixing and reacting step of supplying the metal ion, the hydroxide ion, and a silane coupling agent to a reaction field to mix and react the ions.

Abstract: A method is described for batchwise slaking of burnt lime in a slaker, in which a lime slurry is produced with a greater degree of fineness and prolonged sedimentation time, comprising the following processing steps: emptying of finished slaked and diluted lime slurry from the slaker; automatic coupling of a control system for automatic operation after the wanted slaking temperature has been reached in the first batch; automatic regulation of the slaking temperature in the subsequent slurry batch; and automatic registering of the remaining amount of slurry in the slaker after complete dosing of lime.

Abstract: The invention relates to a method for producing quick lime from lime stone in a continuous regenerative shaft kiln, characterized in that, starting with standard conditions of excessive combustion air for the operation of this kiln, it especially includes a step where the excessive combustion air is progressively reduced until a content greater than 1000 ppm (in volume) of carbon monoxide is reached in the connection flue between the tanks. An increase in the content of gaseous sulphur dioxide is then observed in the gas flue, with respect to a kiln operated in standard conditions.

Abstract: A method of extracting an alkali metal and/or an alkaline earth metal from a mineral including an alkali metal and/or an alkaline earth metal, or a rock containing the mineral, the method including contacting the mineral, with an aqueous composition including formic acid, and to their use in carbon sequestration.

Abstract: In one embodiment, this invention is directed to a method of recovering metals from a metals bearing material comprising: reducing the particle size of at least a portion of the metals bearing material; mixing the metals bearing material in an acid solution to form a first slurry containing at least alkaline earth metal compounds; separating the at least alkaline earth metal compounds from the first slurry to form a first filtrate and a metals bearing material; leaching metals from the metals bearing material to form a pressure leach solution containing transition metals; precipitating and recovering transition metals from the pressure leach solution. In another aspect, the invention relates to a method for recovering metals from a deoiled and dried coal liquefaction residue that contains spent catalyst originating from a Group VIB metal sulfide catalyst.

Abstract: A method for preparation of a getter material on the basis of intermetallic compounds of barium is described. The method comprises preparing a melt of a ternary mixture containing barium, metal and sodium; directionally solidifying the melt to produce a textured ingot; granulating the textured ingot, thereby obtaining granules having open-ended voids extending therethrough; and evaporating the sodium from the granules by applying a thermovacuum treatment to the granules. The textured ingot comprises a getter body made of intermetallic compounds of barium; and open-ended voids within the getter body.

Abstract: A method of producing fluoroapatite by using a calcium-based compound containing calcium, hydrogen fluoride and phosphoric acid is provided. The method can be produced fluoroapatite having improved acid resistance by reducing an amount of an impurity derived from a raw material to a low or very low level, and ability capable of separating a large amount of a protein due to a large specific surface area thereof. Further, fluoroapatite having high acid resistance and a large specific surface area is also provided. Furthermore, an adsorption apparatus using such fluoroapatite is also provided.

Abstract: The present invention discloses a process for producing a nano calcium carbonate slurry from a feedstock of waste gypsum, wherein: an aqueous gypsum slurry of the feedstock is mixed with ammonia water by stirring; with CO2 injected in the slurry is under continuous stirring until the calcium sulfate in the waste gypsum is completely carbonated into nano calcium carbonate; after filtration, the filter cake is dispersed in water to obtain the nano calcium carbonate slurry. This process is easy to operate and to obtain a low-cost and a lower decomposition temperature of calcium carbonate. The present invention also discloses a nano calcium carbonate slurry and its application in preparation of a CaO-based carbon dioxide adsorbent and complex catalyst used for a reactive sorption enhanced reforming process for hydrogen production from methane.

Abstract: A process for extracting metal values from ores or residues is disclosed. The process mentioned above is mainly suitable for aluminoferrous ores such as bauxite, titanoferrous ores such as ilmenite, or residues such as red mud waste. The process involves pulverizing the ore and/or residue and mixing with a carbonaceous material, followed by smelting the iron values and slag in the mixture to yield molten iron and oxides of aluminum and titanium. The process is simple, cost-effective, and provides effective extraction of high purity metal values.

Abstract: A method for synthesizing strontium cerate (SrCeO3) nanoparticles is disclosed. Initially, ammonium cerium(IV) nitrate ((NH4)2Ce(NO3)6) and n-butanol (C4H10O) are reacted to synthesize cerium-n-butoxide (Ce(OBu)4). Next, the cerium-n-butoxide, strontium acetate (Sr(CH3COO)2), and stearic acid (C18H36O2) are reacted to form a homogenous product including the strontium cerate nanoparticles. Finally, the strontium cerate nanoparticles are isolated from the homogenous product.

Abstract: This application concerns methods and apparatus for use in industrial waste recovery operations such as recovery of non-consumed chemicals in industrial processes, with recovery of quick lime in a wood pulp process being an example. In some embodiments, methods comprise baking lime sludge in a kiln and controlling a temperature in a calcining zone of the kiln to be above about 2250° F. to vaporize sodium contained in the lime sludge. Interaction of the vaporized sodium with SOx can deter accumulation of one or both of CaCO3 and CaSO4 on one or more inner surfaces of the kiln. In some embodiments, lime sludge can be rinsed to generate a filtrate comprising dissolved NaOH, and the filtrate can charge a scrubber for removing SOx from an exhaust from the kiln. Embodiments of co-fired burners for heating such kilns by burning petroleum coke and natural gas are also disclosed.

Abstract: The present invention resides in a process of recovering nickel and cobalt, regenerating the main raw materials, said process including the steps of: granulometric separation; leaching; neutralization; MHP production in only one stage and the pressure crystallization of magnesium sulphite. The process proposes a way to recovery nickel and cobalt from laterite ores through the atmospheric and heap leaching with staged addition of ore—by size separation—and H2SO4, decreasing the nickel losses and simplifying the neutralization circuit and producing a more purified MHP. The present process route is employed for nickel extraction, including the one from high magnesium containing lateritic ores.

Abstract: Calcium (Ca), manganese (Mn) and magnesium (Mg) carbonate plus lead (Pb) and zinc (Zn) sulphide minerals in a permeable host, crushed ore, concentrates or as mine discharge tailing are selectively solution mined (in-situ or ex-situ) with a selected acid e.g. acetic acid to extract Ca, Mn, and Mg followed by multivalent oxidizing salts e.g. ferric salts to extract Pb and Zn sequentially. For in-situ leaching, an inter relationship has been identified between pressure, temperature, target depth and leachate concentration such that carbonate leaching is performed in a manner to prevent carbon dioxide gas (CO2) discharge thereby plugging host rock permeability avenues to preclude further leaching. This requires controlling the rate of acetic acid leaching to be in step with availability of solution to dissolve the resulting discharged CO2. Sulphide leaching is subsequently conducted on the carbonate-depleted host.

Abstract: Disclosed herein is an radioisotope adsorbent including a bifunctional organosilane compound, including an organosiloxane functional group and a phosphate group, bonded on the surface of silica which is a bone structure of the adsorbent, and a method of preparing the radioisotope adsorbent, and a strontium/yttrium generator using the radioisotope adsorbent. Since the radioisotope adsorbent has a high adsorption capacity for 90Y such as 95% extraction efficiency or more from ICi 90Sr/90Y by using a column packed with 0.4 g of the adsorbent with a high-purity of 90Y, it can be usefully to be employed in the fields requiring 90Y.

Abstract: CO2-sequestering formed building materials are provided. The building materials of the invention include a composition comprising a carbonate/bicarbonate component. Additional aspects of the invention include methods of making and using the CO2-sequestering formed building material.

Abstract: A thermistor based on a composition having the general formula (I): Re2-x-yCraMnbMcEyOz wherein Re is a rare earth metal or a mixture of two or more rare earth metals, M is a metal selected from the group consisting of nickel, cobalt, copper, magnesium and mixtures thereof, E is a metal selected from the group consisting of calcium, strontium, barium and mixtures thereof, x is the sum of a+b+c and is a number between 0.1 and 1, and the relative ratio of the molar fractions a, b and c is in an area bounded by points A, B, C and D in a ternary diagram, wherein point A is, if y<0.006, at (Cr=0.00, Mn=0.93+10?y, M=0.07?10?y), and, if y?0.006, at (Cr=0?00, Mn=0.99, M=0.01), point B is, if y<0.006, at (Cr=0.83, Mn=0.10+10?y, M=0.07?10?y), and, if y?0.006, at (Cr=0.83, Mn=0.16, M=0.01), point C is at (Cr=0.50, Mn=0.10, M=0.40) and point D is at (Cr=0.00, Mn=0.51, M=0.49), y is a number between 0 and 0.5?x, and z is a number between 2.5 and 3.5.

Abstract: A process for sequestrating carbon emitted into the atmosphere in the form of CO2 comprises: a) a step for concentrating CO2 in the liquid phase; b) a step for electro-reduction in an aprotic medium to a compound in which the carbon changes to oxidation number +3 in the form of oxalic acid or formic acid; c) if appropriate, a step for re-extracting oxalic or formic acid in the aqueous phase; and d) a step for mineralization by reaction with a compound of an element M, resulting in a stable compound in which the atomic ratio C/M is about 2/1.

Abstract: A method of recovering a mineral product from carpet by preparing a feed of carpet pieces; thermally separating organic components from mineral components in the carpet by heating the carpet pieces to a particle bed temperature in the range of 600° C. to 1000° C., wherein the mineral component is oxidized to form a mineral oxide; slurrying the mineral oxide with water to produce 15 to 35% solids slurry within a period of approximately 30 minutes to 24 hours, whereby the mineral oxide forms a mineral hydroxide; stabilizing the pH of the slurry in the range between 6 and 10 by carbonation, resulting in a slurry containing mineral carbonates.

Abstract: A process for formulating high purity potassium chloride from a carnallite source. The process takes advantage of solubility differences and saturation levels in a multiple salt system generated upon dissolution of carnallite. In the system, the sodium chloride is kept in solution and the magnesium chloride present in the system is controlled to be in a concentration range of between 12% and 25% by weight. This avoids co-precipitation of sodium chloride with the potassium chloride during crystallization and therefore prevents the sodium chloride from contaminating the potassium chloride. The result is high grade potassium chloride.

Abstract: Methods and systems for enhancing rates of carbonation of peridotite both in situ and ex situ are disclosed. In some embodiments, the methods and systems include the following: fracturing a volume of peridotite; heating the volume of peridotite; injecting an adjustable flow of carbon dioxide into the volume of peridotite; injecting bicarbonate materials into the volume of peridotite; and forming carbonate with the volume of peridotite and the carbon dioxide in an exothermic reaction thereby generating a self-sustaining heat source, the heat source heating the volume of peridotite.

Abstract: A method and apparatus for recovering a metal and separating arsenic from an arsenic-containing solution. The method includes contacting the arsenic-containing solution with a fixing agent that comprises a rare earth compound to produce an arsenic-depleted solution and an arsenic-laden fixing agent. The fixing agent comprises a rare earth-containing compound that can include cerium, lanthanum, or praseodymium. The fixing agent is separated from the arsenic-depleted solution and a recoverable metal is separated from one or more of the arsenic-containing solution and the arsenic-depleted solution. Recoverable metals can include metal from Group IA, Group IIA, Group VIII and the transition metals. The arsenic-containing solution can be formed by contacting an arsenic-containing material with a leaching agent. Arsenic-depleted solids formed during the leach can also be separated and recovered.