US 12,247,305 B2
Electrolytic generation and purification of carbon
Drew Lawrence Reid, Berkeley, CA (US); Benjamin Mark Rush, Oakland, CA (US); Daniel Ricardo Ahumada, Berkeley, CA (US); and Kenneth Reid, Piedmont, CA (US)
Assigned to Maple Materials, Inc., Richmond, CA (US)
Filed by Maple Materials, Inc., Richmond, CA (US)
Filed on Dec. 15, 2020, as Appl. No. 17/247,533.
Application 17/247,533 is a division of application No. 16/146,882, filed on Sep. 28, 2018, granted, now 10,900,134.
Claims priority of provisional application 62/564,956, filed on Sep. 28, 2017.
Prior Publication US 2021/0108320 A1, Apr. 15, 2021
Int. Cl. C25B 15/08 (2006.01); C25B 1/00 (2021.01); C25B 1/135 (2021.01); C25B 1/14 (2006.01); C25B 9/09 (2021.01); C25B 9/19 (2021.01); C25B 11/042 (2021.01); C25B 11/046 (2021.01)
CPC C25B 15/08 (2013.01) [C25B 1/00 (2013.01); C25B 1/135 (2021.01); C25B 1/14 (2013.01); C25B 9/09 (2021.01); C25B 9/19 (2021.01); C25B 11/042 (2021.01); C25B 11/046 (2021.01); C25B 15/081 (2021.01); C25B 15/087 (2021.01)] 14 Claims
OG exemplary drawing
 
1. A system for producing and purifying carbon and recovering lithium carbonate, the system comprising:
an electrolysis reactor configured to produce a solid reaction product by reducing carbonate ions at a cathode in a molten carbonate salt electrolyte, wherein the molten carbonate salt electrolyte comprises lithium carbonate, and wherein the solid reaction product comprises carbon, lithium oxide, and the lithium carbonate from the molten carbonate salt electrolyte;
a grinder configured to receive the solid reaction product and grind it into a powdered form having an average particle diameter between about 0.5-5 mm;
a washer configured to contact the powdered form of the solid reaction product with water to react at least some of the lithium oxide with the water to form lithium hydroxide;
a filter configured to separate the lithium hydroxide from the solid carbon and lithium carbonate in the solid reaction product, thereby forming a filtered solid reaction product;
an extraction vessel configured to hold carbon dioxide, a hydrogen ion-donor solvent, and the filtered solid reaction product therein, wherein the extraction vessel is configured to reach a target pressure of at least about 1 atmosphere while the filtered solid reaction product, carbon dioxide, and hydrogen ion-donor solvent are held therein, thereby (i) producing lithium bicarbonate from the lithium carbonate, and (ii) forming a mixture comprising purified solid carbon and a solution of (a) the lithium bicarbonate, (b) the carbon dioxide, and (c) the hydrogen ion-donor solvent, wherein the target pressure is a total absolute pressure in the extraction vessel;
a separator for separating the purified solid carbon from the mixture;
an evaporation reactor configured to receive the solution after the purified solid carbon is removed from the mixture, wherein the evaporation reactor is configured to evaporate the carbon dioxide and the hydrogen ion-donor solvent from the solution to provide recovered lithium carbonate; and
a precipitation reactor configured to react carbon dioxide with the lithium hydroxide to form a second recovered lithium carbonate and recovered water,
wherein the electrolysis reactor is configured to receive the recovered lithium carbonate from the evaporation reactor.