A system for decomposing a waste material in an unlined landfill including a landfill site having at least one waste disposal zone for receiving the waste material. The system also includes a remediation system configured for extracting a mixture of leachate and groundwater from groundwater within or adjacent to the landfill site and feeding the mixture into the at least one waste disposal zone along with air and other nutrients to enhance a rate of decay of the waste material within the at least one waste disposal zone.

A system for decomposing a waste material in an unlined landfill including a landfill site having at least one waste disposal zone for receiving the waste material. The system also includes a remediation system configured for extracting a mixture of leachate and groundwater from groundwater within or adjacent to the landfill site and feeding the mixture into the at least one waste disposal zone along with air and other nutrients to enhance a rate of decay of the waste material within the at least one waste disposal zone.

Improved methods for the removal of heavy metals, in particular cadmium, from an aqueous phosphoric acid containing composition, wherein an organothiophosphorous heavy metal precipitating agent and an ionic polymeric surfactant, particularly a cationic polyacrylamide copolymer surfactant, are both added to a phosphoric acid containing composition, particularly under vigorous mixing conditions, such as between 500 and 700 rpm. The ionic polymeric surfactant promotes the precipitation of the heavy metals. More in particular, the phosphoric acid containing composition is obtained by the acid digestion of phosphate rock, preferably by nitric acid, sulfuric acid, or a combination thereof.

Porous amorphous silica can be obtained from siliceous plant matter containing non-siliceous inorganic substances. The siliceous plant matter is soaked in an aqueous solution which includes a chelating agent. The chelating agent is present in an amount which helps to extract at least some of the non-siliceous inorganic matter. The aqueous solution is then separated from the siliceous plant matter. Beneficial properties are imparted to the siliceous plant matter by controlling the amount of at least one preselected non-siliceous inorganic substance in the siliceous plant matter. At the end of the process, the siliceous plant matter is heat treated in the presence of oxygen at a temperature to produce the resulting amorphous silica having the beneficial properties.

A method for recovering lithium from lithium ion battery scrap according to this invention comprises subjecting lithium ion battery scrap to a calcination step, a crushing step, and a sieving step sequentially carried out, wherein the method comprises, between the calcination step and the crushing step, between the crushing step and the sieving step, or after the sieving step, a lithium dissolution step of bringing the lithium ion battery scrap into contact with water and dissolving lithium contained in the lithium ion battery scrap in the water to obtain a lithium-dissolved solution; a lithium concentration step of solvent-extracting lithium ions contained in the lithium-dissolved solution and stripping them to concentrate the lithium ions to obtain a lithium concentrate; and a carbonation step of carbonating the lithium ions in the lithium concentrate to obtain lithium carbonate.

A method for recovering lithium from lithium ion battery scrap according to this invention comprises subjecting lithium ion battery scrap to a calcination step, a crushing step, and a sieving step sequentially carried out, wherein the method comprises, between the calcination step and the crushing step, between the crushing step and the sieving step, or after the sieving step, a lithium dissolution step of bringing the lithium ion battery scrap into contact with water and dissolving lithium contained in the lithium ion battery scrap in the water to obtain a lithium-dissolved solution; a lithium concentration step of solvent-extracting lithium ions contained in the lithium-dissolved solution and stripping them to concentrate the lithium ions to obtain a lithium concentrate; and a carbonation step of carbonating the lithium ions in the lithium concentrate to obtain lithium carbonate.

In a method for recycling all solid-state batteries, spent battery cells are dissolved in anhydrous ethanol. The resulting solution is separated into solids and supernatants which are separately processed to regenerate the solid electrolyte and the solid electrode materials. The supernatant is subjected to vacuum evaporation to precipitate an electrolyte powder, which is then annealed under flowing oxygen. The solid electrode material is regenerated by washing the solids with water, drying the washed solids, relithiating the washed solids, and annealing the relithiated solids. The resulting materials are suitable for use in fabrication of new all-solid state batteries.

In a method for recycling all solid-state batteries, spent battery cells are dissolved in anhydrous ethanol. The resulting solution is separated into solids and supernatants which are separately processed to regenerate the solid electrolyte and the solid electrode materials. The supernatant is subjected to vacuum evaporation to precipitate an electrolyte powder, which is then annealed under flowing oxygen. The solid electrode material is regenerated by washing the solids with water, drying the washed solids, relithiating the washed solids, and annealing the relithiated solids. The resulting materials are suitable for use in fabrication of new all-solid state batteries.

A method comprising a) mixing and dissolving the solid hazardous heavy metal-containing composition with an acid solution; b) precipitating the heavy metal from the hazardous heavy metal acid composition; c) precipitating the heavy metal from the hazardous heavy metal acid composition with a heavy metal-precipitation agent; and d) separating out the heavy metal precipitate from the aqueous supernatant, whereby the heavy metal-precipitation agent comprises a diorgano-dithiophosphinic acid or the alkali metal or ammonia salts thereof.

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A method comprising a) mixing and dissolving the solid hazardous heavy metal-containing composition with an acid solution; b) precipitating the heavy metal from the hazardous heavy metal acid composition; c) precipitating the heavy metal from the hazardous heavy metal acid composition with a heavy metal-precipitation agent; and d) separating out the heavy metal precipitate from the aqueous supernatant, whereby the heavy metal-precipitation agent comprises a diorgano-dithiophosphinic acid or the alkali metal or ammonia salts thereof.

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