Remediation of marine dead zones by enhancing microbial sulfide oxidation using electrodes (REDOX)

Coastal marine environments suffer from seasonal and sometimes permanent anoxia. These waters are often referred to as dead zones due to the lack of oxygen and the accumulation of hydrogen sulfide (H2S). This project will develop a novel yet simple approach to remediating these waters by using electrodes to connect the otherwise segregated anoxic bottom waters to the oxygen-rich top waters. The subsequent flow of electrons results in the oxidation of H2S to elemental sulfur. The benefits of sulfide removal are two-fold. It will reduce oxygen demand allowing any natural mixing of oxygen (wind driven) to immediately contribute to improving oxygen conditions. Secondly, it will improve conditions as sulfide itself is an extremely toxic substance to all higher (aerobic) life forms and its occurrence has disastrous consequences for benthic marine ecosystems. Our goal is to scale up from completed laboratory tests to a field demonstration of the potential benefits of the approach on chemical and biological water quality.