Capturing Carbon from Oceans

The ocean is a global-scale reservoir of atmospheric CO2. The removal of CO₂ from ocean water is thus considered a promising approach to reduce ambient CO₂, and potentially achieve net-negative emissions.

The Technology Behind Capturing Carbon from Ocean

An asymmetric electrochemical system employing bismuth and silver electrodes that can capture and release chloride ions by faradaic reactions upon application of appropriate cell voltages. The difference in reaction stoichiometry between the two electrodes enables an electrochemical system architecture for a chloride-mediated electrochemical pH swing, which can be leveraged for the effective removal of CO₂ from ocean water without costly bipolar membranes. With two silver–bismuth systems operating in tandem in a cyclic process, one acidifying the ocean water, and the other regenerating the electrodes through alkalization of the treated stream, CO₂ can be continuously removed from simulated oceanwater with a relatively low energy consumption of 122 kJ mol⁻¹, and high electron efficiency. [Source]

Read More: Sustainable Material for Automotive Parts

General Process of CCUS

Seawater has more than 100 times the concentration of CO2 than air, and the oceans absorb 26 percent of the CO2 that humans cause, which contributes to widespread ocean acidification. The MIT researchers stress the significance of water-based carbon capture. They recognize the urgency of lowering CO2 in oceans because they absorb an enormous quantity of carbon compared to the atmosphere and terrestrial ecosystems combined.

By 2025, the suggested technology will be available for demonstration, which could effectively solve this problem.