[Problem] To provide a magnesium hydroxide-based solid solution which has smaller primary particles and secondary particles and improved reactivity with an acid as compared with conventional magnesium hydroxide (Mg(OH).sub.2), improves the flame retardancy and mechanical strength of a resin, and also forms a non-sedimenting slurry, providing the same handleability as a liquid.

[Structure] A magnesium hydroxide-based solid solution represented by the following formula (1): Mg(OH).sub.2-xR.sub.x (Formula 1), wherein R represents a monovalent organic acid, and x represents 0<x<1. The magnesium hydroxide-based solid solution is a magnesium oxide (MgO) precursor. A flame retardant for a synthetic resin, including the magnesium hydroxide-based solid solution as an active ingredient. A synthetic resin composition characterized by including 0.1 to 50 parts by weight of the magnesium hydroxide-based solid solution (b) per 100 parts by weight of a synthetic resin (a); and a molded article thereof.

A method for preparing lithium concentrate from natural lithium-bearing brines was developed. The brine is first subjected to purification from the suspended solids, then filtered through a static layer of a granulated sorbent based on LiCl.2Al(OH).sub.3.mH.sub.2O, where m=3-5, to obtain a primary lithium concentrate. The process is carried out in sorption-desorption units consisting of 4 columns, two of which are in the process of sorption of lithium chloride from the brine, one column is in the process of washing the sorbent saturated with lithium chloride from the brine, and one column is in the process of lithium chloride desorption. The primary lithium concentrate is converted to a secondary lithium concentrate by concentration in evaporative pools or reverse osmotic concentration-desalination. The secondary lithium concentrate is used for further production of lithium chloride or lithium carbonate.

Nanoplatelet forms of monolayer metal hydroxides are provided, as well as methods for preparing same. The nanoplatelets are suitable for use in antimicrobial compositions, for pressure treating lumber against wood rot, termites, and fungus, for water treatment for the removal of heavy metal contaminants, for the production of plasmonics devices, for the production of ore, or for the recovery of valuable metals in, e.g., fly ash ponds, mine tailings ponds, or other fluids containing the metal in ionic form. The nanoplatelet forms include copper hydroxide nanoplatelets.

Methods for fabrication of and use of magnesium oxide sorbents for room temperature carbon dioxide adsorption are provided. In accordance with one aspect, a method for fabrication of sorbents is provided which includes using calcination to obtain MgO—Mg(OH).sub.2 nano-composites and aging the MgO—Mg(OH).sub.2 nano-composites to form nano MCHs for room temperature carbon dioxide adsorption. According to another aspect, a method for fabrication of sorbents which includes fabrication of monoclinic magnesium malate tetrahydrate (C.sub.8H.sub.10MgO.sub.10.4H.sub.2O) and use of such sorbents for room temperature carbon dioxide adsorption is provided.

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.

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.

A method and system for producing highly activated silicate material, wherein the silicate source material is provided for reaction with a reforming agent in a reforming process. The reforming process is a hydrothermal process and/or a high temperature silicate reforming (HTSR) process. A heat source heats reaction materials to a reaction temperature in the presence of a reaction medium. For the hydrothermal reaction process, the reaction medium and heat source are an exhausted steam that is a byproduct of another industrial process. For the HTSR process, the silicate source material and the heat source are a molten slag byproduct from another industrial process.

A method and system for producing highly activated silicate material, wherein the silicate source material is provided for reaction with a reforming agent in a reforming process. The reforming process is a hydrothermal process and/or a high temperature silicate reforming (HTSR) process. A heat source heats reaction materials to a reaction temperature in the presence of a reaction medium. For the hydrothermal reaction process, the reaction medium and heat source are an exhausted steam that is a byproduct of another industrial process. For the HTSR process, the silicate source material and the heat source are a molten slag byproduct from another industrial process.

Systems and methods are described in which spent pickle liquor from metal cleaning processes is utilized to regenerate a lixiviant used to recover valuable metals from industrial waste and other sources. The spent pickle liquor is neutralized and solvated metals in the spent pickle liquor are precipitated in this process. When the industrial waste is slag from a metal refining process a partially closed metal production process can be implemented, where spent pickle liquor from cleaning of the refined metal is used to regenerate a lixiviant used to recover a different, valuable metal from a waste slag of the process, with precipitated salts from the lixiviant regeneration being returned as a raw material in the metal refining process. As a result waste streams from these processes are dramatically reduced or eliminated.

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.