Some aspects of the present disclosure relate to systems and processes for the conversion of lithium phosphate into a low-phosphate solution containing lithium which may be suitable as feedstock for the production of saleable lithium products.

Some aspects of the present disclosure relate to systems and processes for the conversion of lithium phosphate into a low-phosphate solution containing lithium which may be suitable as feedstock for the production of saleable lithium products.

A method for producing mesoporous magnesium hydroxide nanoplates involving solvothermal treatment of a solution of a magnesium salt, a base, a glycol, and water is disclosed. The method does not use a surfactant or template in the solvothermal treatment. The method yields mesoporous nanoparticles of magnesium hydroxide having a plate-like morphology with a diameter of 20 nm to 100 nm, a mean pore diameter of 2 to 10 nm, a surface area of 50 to 70 m.sup.2/g, and a type-III nitrogen adsorption-desorption BET isotherm with a H3 hysteresis loop. An antibacterial composition containing the mesoporous magnesium hydroxide nanoplates is also disclosed. A method for reducing nitroaromatic compounds with a reducing agent and the mesoporous magnesium hydroxide nanoplates as a catalyst is also disclosed.

Nanoplatelet forms of metal hydroxide and metal oxide are provided, as well as methods for preparing same. The nanoplatelets are suitable for use as fire retardants and as agents for chemical or biological decontamination.

Nanoplatelet forms of metal hydroxide and metal oxide are provided, as well as methods for preparing same. The nanoplatelets are suitable for use as fire retardants and as agents for chemical or biological decontamination.

The present invention discloses a method for producing lithium carbonate from a low-lithium brine by separating magnesium and enriching lithium. A salt-lake brine is used as a raw material and is converted into halide salts through dehydration by evaporation and separation by crystallization; the halide salts are directly extracted using trialkyl phosphate or a mixture of trialkyl phosphate and monohydric alcohol, and an organic extraction phase as well as remaining halide salts are obtained after solid-liquid separation; reverse extraction is performed on the organic extraction phase to obtain a lithium-rich solution with a low magnesium-to-lithium ratio, and lithium carbonate is obtained after concentration and removal of magnesium by alkalization. The used solid-liquid extraction method is simple with no co-extraction agent used, and a solute distribution driving force is strong, unaffected by phase equilibrium of the brine extraction agent. The mass ratio of magnesium-to-lithium significantly decreases in the extraction phase.

The present invention discloses a method for producing lithium carbonate from a low-lithium brine by separating magnesium and enriching lithium. A salt-lake brine is used as a raw material and is converted into halide salts through dehydration by evaporation and separation by crystallization; the halide salts are directly extracted using trialkyl phosphate or a mixture of trialkyl phosphate and monohydric alcohol, and an organic extraction phase as well as remaining halide salts are obtained after solid-liquid separation; reverse extraction is performed on the organic extraction phase to obtain a lithium-rich solution with a low magnesium-to-lithium ratio, and lithium carbonate is obtained after concentration and removal of magnesium by alkalization. The used solid-liquid extraction method is simple with no co-extraction agent used, and a solute distribution driving force is strong, unaffected by phase equilibrium of the brine extraction agent. The mass ratio of magnesium-to-lithium significantly decreases in the extraction phase.

A method for removing alkali earth metals from a filtrate including a first crystallization step and a second crystallization step, wherein the first crystallization step is a forced circulation crystallizer, and wherein the second crystallization step is a draft tube crystallizer. Also included is a method for reducing magnesium in a chemical liquor including crystallizing magnesium into a magnesium sulfate hydrate in a first crystallization step and precipitating magnesium via addition of a caustic material in a chemical precipitation step.

A method for removing alkali earth metals from a filtrate including a first crystallization step and a second crystallization step, wherein the first crystallization step is a forced circulation crystallizer, and wherein the second crystallization step is a draft tube crystallizer. Also included is a method for reducing magnesium in a chemical liquor including crystallizing magnesium into a magnesium sulfate hydrate in a first crystallization step and precipitating magnesium via addition of a caustic material in a chemical precipitation step.

A process for recovering lithium chloride from a lithium sulfate (Li.sub.2SO.sub.4)-containing mixture is described, comprising a step of sulfate removal using barium chloride (BaCl.sub.2). In embodiments, the process may further comprise one or more steps to reduce the level of one or more metals other than lithium and to reduce the level of sulfate by increasing the pH of the (Li.sub.2SO.sub.4)-containing mixture, e.g., using a calcium salt. In embodiments, treatments to reduce the level of one or more metals other than lithium, sulfate, and other components (e.g., calcium if used) may be used, producing a solution substantially comprising Li.sub.2SO.sub.4 for barium chloride (BaCl.sub.2) treatment, to form a precipitate comprising barium sulfate (BaSO.sub.4) and a solution substantially comprising lithium chloride.