The present invention is directed to an electrochemical device for at least partially removing or reducing a target ionic species from an aqueous solution using faradic immobilization, the electrochemical device including at least one first electrode and at least one second electrode with different void fraction and surface area properties, due to differences in void fraction (also referred to as void ratio) of the at least one first and the at least one second electrode, water flows through an electrode with a high porosity, while the aqueous solution does not flow through an electrode with a low porosity. The asymmetry of the electrodes provides a desired voltage distribution across the device, which equates to a different voltage at each electrode, to control the speciation of the target ionic species at the anode and the cathode.

This invention relates to a method for the preparation of lithium carbonate from lithium chloride containing brines. The method can include a silica removal step, capturing lithium chloride, recovering lithium chloride, supplying lithium chloride to an electrochemical cell and producing lithium hydroxide, contacting the lithium hydroxide with carbon dioxide to produce lithium carbonate.

This invention relates to a method for the preparation of lithium carbonate from lithium chloride containing brines. The method can include a silica removal step, capturing lithium chloride, recovering lithium chloride, supplying lithium chloride to an electrochemical cell and producing lithium hydroxide, contacting the lithium hydroxide with carbon dioxide to produce lithium carbonate.

The invention regards a method for electrochemical ammonia synthesis, comprising the steps of: providing at least one electrolysis cell; contacting the cathode with a source of lithium cations, nitrogen, and protons; and subjecting the cathode to a continuous pulsed cathode potential, including a pulsed cathodic current load, wherein the cathode potential is pulsed between the lithium reduction potential and a less negative cathode potential, whereby ammonia is synthesized.

New dual temperature electrochemical methods and systems for the production of sodium metal from sodium polysulfides have been discovered. The technology provides high conductivity for sodium ions and extended service life for the electrochemical cell.

New dual temperature electrochemical methods and systems for the production of sodium metal from sodium polysulfides have been discovered. The technology provides high conductivity for sodium ions and extended service life for the electrochemical cell.

A method and electrolysis cell for producing lithium metal at a low temperature. The method includes combining (i) acetonitrile and (ii) a cation bis(trihaloalkylsulfonyl)imide, cation bis(trihalosulfonyl)imidic acid, a cation bis(trihaloalkylsulfonyl)amide, or cation bis(trihaloalkylsulfonyl)amidic acid in a weight ratio of (i) to (ii) about 100:1 to about 5:1 to provide a non-aqueous electrolyte composition. A lithium compound selected from the group consisting of LiOH, Li.sub.2O and Li.sub.2CO.sub.3 is dissolved in the electrolyte composition to provide a lithium doped electrolyte composition. Power is applied to the electrolyte composition to form lithium metal on a cathode of an electrolysis cell. The lithium metal separated from the cathode has a purity of at least about 95 wt. %.

A method and electrolysis cell for producing lithium metal at a low temperature. The method includes combining (i) acetonitrile and (ii) a cation bis(trihaloalkylsulfonyl)imide, cation bis(trihalosulfonyl)imidic acid, a cation bis(trihaloalkylsulfonyl)amide, or cation bis(trihaloalkylsulfonyl)amidic acid in a weight ratio of (i) to (ii) about 100:1 to about 5:1 to provide a non-aqueous electrolyte composition. A lithium compound selected from the group consisting of LiOH, Li.sub.2O and Li.sub.2CO.sub.3 is dissolved in the electrolyte composition to provide a lithium doped electrolyte composition. Power is applied to the electrolyte composition to form lithium metal on a cathode of an electrolysis cell. The lithium metal separated from the cathode has a purity of at least about 95 wt. %.

Disclosed are methods for direct electrodeposition of a metal from the liquid medium. The methods include electro-reduction of lithium anions on cathode electrodes in the presence of various metal deposition selectivity enhancements. The selectivity enhancement disclosed herein comprises the presence of a magnet, a solvent that is immiscible with an original liquid medium comprising the desired metal ions or various separators. Also disclosed are systems for electrodeposition of the desired metals from the liquid medium.

Disclosed are methods for direct electrodeposition of a metal from the liquid medium. The methods include electro-reduction of lithium anions on cathode electrodes in the presence of various metal deposition selectivity enhancements. The selectivity enhancement disclosed herein comprises the presence of a magnet, a solvent that is immiscible with an original liquid medium comprising the desired metal ions or various separators. Also disclosed are systems for electrodeposition of the desired metals from the liquid medium.