Carbon dioxide (CO2) mitigation has been shown to be vital towards solving global climate change and ocean acidification. Current methods to scrub CO2 from fossil fuel point emissions, however, require heavy energy expenditure and cannot remove existing CO2 from the atmosphere. This technology is an energy-neutral, reusable system that can remove CO2 from both point sources and the atmosphere by using common minerals as a carbon sink. Together, this technology provides useable and economically viable methods for handling global warming via CO2 capture.
This technology utilizes highly abundant magnesium silicate minerals such as olivine. These minerals are dissolved in aqueous acid and subsequently precipitated with ammonia. The precipitated magnesium is carbonated by treatment with CO2 to produce magnesium carbonate that is safely disposed of. This process, named enhanced weathering, is highly effective at sequestering CO2. Further, the exothermic nature of this reaction allows excess energy to be used to thermally decompose or electrolyze the ammonia solution, thus recycling the acid and ammonia. Compared with existing approaches, this recycling method is energetically neutral. This technology also describes a method in which CO2 is absorbed into a basic solution and sequestered into calcium carbonate using slaked lime in an ion-exchange process.
This technology has been validated through several successful carbon sequestration projects.
Tech Ventures Reference: IR M04-022