Energy recovery from the carbon dioxide for green and sustainable environment using iron minerals as electron donor

Abstract

Biotransformation of the greenhouse gas carbon dioxide to valuable chemicals has attracted enormous attention because of its importance for sustainable environment and a potential green production strategy. This study investigated a microbial driven process for energy production from carbon dioxide by converting it to value-added chemicals using iron minerals as electron donors with an enriched microbial consortium from oil field production water as the biocatalysts. Enhanced production of the bioenergy methane and short-chain fatty acids was observed in the treatments amended with iron minerals compared to the controls without amendment. Analysis of the microbial community population revealed that Methanosarcina mazei and acetogenic bacteria especially Clostridiaceae were responsible to produce methane and volatile fatty acids, respectively. The results indicate that direct electron transfer was facilitated in the process along with hydrogen generation and chemical catalysis by minerals. The main limiting factors in the process were chemical composition, specific surface area and dissolution rate of the minerals. Formation of iron carbonate was detected indicating a potential strategy for capture and storage of carbon dioxide as carbonate minerals in reservoirs. The study yielded new insights about the potential of the earliest biochemical metabolism on earth for carbon dioxide reduction to biochemicals for microbial life, and also sustainable environmental management. It also suggests a technologically and economically feasible strategy for large-scale commercial storage of carbon dioxide in the petroleum and underground reservoirs for energy recovery and cleaner production of chemicals in an environmental efficient way.