This invention relates to treated geothermal brine compositions containing reduced concentrations of lithium, iron and silica compared to the untreated brines. Exemplary compositions contain concentration of lithium ranges from 0 to 200 mg/kg, concentration of silica ranges from 0 to 30 mg/kg, concentration of iron ranges from 0 to 300 mg/kg. Exemplary compositions also contain reduced concentrations of elements like arsenic, barium, and lead.

This invention relates to treated geothermal brine compositions containing reduced concentrations of lithium, iron and silica compared to the untreated brines. Exemplary compositions contain concentration of lithium ranges from 0 to 200 mg/kg, concentration of silica ranges from 0 to 30 mg/kg, concentration of iron ranges from 0 to 300 mg/kg. Exemplary compositions also contain reduced concentrations of elements like arsenic, barium, and lead.

Methods, systems and lixiviation compositions including an ammonium thiosulfate or a non-ammonium thiosulfate component in combination with one or more alkaline earth metal hydroxides, and optionally copper cations, for leaching precious metals from a precious metal containing material. The alkaline earth metal hydroxides may include magnesium hydroxide, calcium hydroxide, or a combination of magnesium hydroxide and calcium hydroxide.

Methods, systems and lixiviation compositions including an ammonium thiosulfate or a non-ammonium thiosulfate component in combination with one or more alkaline earth metal hydroxides, and optionally copper cations, for leaching precious metals from a precious metal containing material. The alkaline earth metal hydroxides may include magnesium hydroxide, calcium hydroxide, or a combination of magnesium hydroxide and calcium hydroxide.

Hydrometallurgical compositions are described in which organic amine-based lixiviants and organic amine-based pre-lixiviants are utilized in the selective recovery of rare earth elements. The lixiviant species can be regenerated in situ, permitting the organic amine to be used in substoichiometric amounts.

Hydrometallurgical compositions are described in which organic amine-based lixiviants and organic amine-based pre-lixiviants are utilized in the selective recovery of rare earth elements. The lixiviant species can be regenerated in situ, permitting the organic amine to be used in substoichiometric amounts.

Methods and compositions are described in which amine-based compounds are utilized in the recovery of rare earth elements from solution. The rare earth elements are recovered selectively and sequentially.

Methods and compositions are described in which amine-based compounds are utilized in the recovery of rare earth elements from solution. The rare earth elements are recovered selectively and sequentially.

The present disclosure relates to a method for determining a source sink term of an ionic type rare earth ore leaching process. The method includes the following four steps: (1) determining an ion exchange selection coefficient of a rare earth ore sample; (2) determining the rare earth grade of the rare earth ore sample; (3) building a source sink term model of the ore leaching process; and (4) determining parameters in the source sink term model. The present disclosure can simulate the ionic type rare earth ore leaching process by combining a convection-dispersion equation, and determine the optimal concentration of the ore leaching agent. When an ammonium sulfate solution at an optimal concentration of 12.0 g/L is used to perform a column leaching test, the obtained rare earth leaching rate is up to 96.3 percent.

The present disclosure relates to a method for determining a source sink term of an ionic type rare earth ore leaching process. The method includes the following four steps: (1) determining an ion exchange selection coefficient of a rare earth ore sample; (2) determining the rare earth grade of the rare earth ore sample; (3) building a source sink term model of the ore leaching process; and (4) determining parameters in the source sink term model. The present disclosure can simulate the ionic type rare earth ore leaching process by combining a convection-dispersion equation, and determine the optimal concentration of the ore leaching agent. When an ammonium sulfate solution at an optimal concentration of 12.0 g/L is used to perform a column leaching test, the obtained rare earth leaching rate is up to 96.3 percent.