Captura’s ocean carbon removal technology at the Port of Los Angeles has captured about 100 tons of carbon dioxide over the past year.Every year, hundreds of container ships slide into the Port of Los Angeles, the busiest in the Western Hemisphere. Belching carbon dioxide , they deliver some $300 billion in goods to trucks and railcars that add their own pollution to our warming planet.
But one long gray barge docked at the port is doing its part to combat climate change. On the barge, which belongs to Captura, a Los Angeles–based startup, is a system of pipes, pumps, and containers that ingests seawater and sucks out CO, which can be used to make plastics and fuels or buried.
Captura’s process starts by piping seawater to a reactor that uses electricity to split a few of the water molecules into positively charged protons and negatively charged hydroxyl ions. Those compounds react with sodium and chloride ions in the water to produce hydrochloric acid and sodium hydroxide, a base. The acid reacts with bicarbonate ions in the water, causing COto bubble out into a storage tank.
Ocean capture advocates are seeking more government support. In the United States, direct air capture plants earn a $180 tax credit per ton of sequestered COEven if the technology takes off, it will have to scale up massively to make a dent in offsetting global emissions. According to the Intergovernmental Panel on Climate Change, by 2050 engineered carbon removal efforts will need to remove some 5 billion tons of CO every year to limit the global temperature increase to 1.5°C.