The present invention describes ways of increasing the production efficiency of a saline water electrolysis cell and of consuming CO.sub.2 gas and sequestering it from the atmosphere. This is achieved by the introduction of CO.sub.2 gas into the catholyte of the electrolysis, where reaction of the CO.sub.2 with the hydroxide ions present in the catholyte reduces the pH of the catholyte, thereby increasing production efficiency of the electrolysis cell. The preceding reaction forms bicarbonate and/or carbonate, thus sequestering the reactant CO.sub.2 gas from the atmosphere. The CO.sub.2 gas may be introduced either directly into the cathode area of the electrolysis cell, or into the electrolyte prior to its introduction into the electrolysis cell. Corresponding apparatus is also provided.

Systems and methods are described for producing lithium hydroxide from lithium chloride and sodium chloride through an electrolysis process. A solution of lithium hydroxide and sodium hydroxide may be produced through electrolysis of a lithium chloride and sodium chloride solution. Lithium hydroxide in the produced solution may then be crystallized and filtered out to produce substantially pure lithium hydroxide crystals.

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.

Apparatuses and methods for extracting desired chemical species including, without limitation, lithium, specific lithium species, and/or other chemical compounds from input flows in a modular unit. The input flows may be raw materials in which lithium metal and/or lithium species are dissolved and/or extracted. The apparatuses and methods may include daisy chain flow through separate tanks, a column array, and combinations thereof.

Apparatuses and methods for extracting desired chemical species including, without limitation, lithium, specific lithium species, and/or other chemical compounds from input flows in a modular unit. The input flows may be raw materials in which lithium metal and/or lithium species are dissolved and/or extracted. The apparatuses and methods may include daisy chain flow through separate tanks, a column array, and combinations thereof.

Method and apparatus for a low maintenance, high reliability on-site electrolytic generator incorporating automatic cell monitoring for contaminant film buildup, as well as automatically removing or cleaning the contaminant film. This method and apparatus preferably does not require human intervention to clean. For high current density cells, cleaning is preferably performed by reversing the polarity of the electrodes and applying a lower current density to the electrodes, preferably by adjusting the salinity or brine concentration of the electrolyte while keeping the voltage constant. Electrolyte flow preferably comprises water and brine flows which are preferably separately monitored and automatically adjusted. For bipolar cells, flow between modules arranged in parallel is preferably approximately equally distributed between modules and between intermediate electrodes within each module.

Method and apparatus for a low maintenance, high reliability on-site electrolytic generator incorporating automatic cell monitoring for contaminant film buildup, as well as automatically removing or cleaning the contaminant film. This method and apparatus preferably does not require human intervention to clean. For high current density cells, cleaning is preferably performed by reversing the polarity of the electrodes and applying a lower current density to the electrodes, preferably by adjusting the salinity or brine concentration of the electrolyte while keeping the voltage constant. Electrolyte flow preferably comprises water and brine flows which are preferably separately monitored and automatically adjusted. For bipolar cells, flow between modules arranged in parallel is preferably approximately equally distributed between modules and between intermediate electrodes within each module.

A carbon material has at least either a peak related to diamond bonds, or a peak related to diamond-like bonds, appearing in a range of 1250 to 1400 cm.sup.−1 in a spectrum measured by Raman scattering spectrometry, and a full width at half maximum of a maximum peak, or each of full widths at half maximum of the maximum peak and a second largest peak, among peaks appearing in the range of 1250 to 1400 cm.sup.−1, has a signal less than 100 cm.sup.−1.

A carbon material has at least either a peak related to diamond bonds, or a peak related to diamond-like bonds, appearing in a range of 1250 to 1400 cm.sup.−1 in a spectrum measured by Raman scattering spectrometry, and a full width at half maximum of a maximum peak, or each of full widths at half maximum of the maximum peak and a second largest peak, among peaks appearing in the range of 1250 to 1400 cm.sup.−1, has a signal less than 100 cm.sup.−1.