Utilization of carbon dioxide and nitrate to produce sodium bicarbonate through a nitrate hydrogenation method

Abstract

Sodium carbonate (Na₂CO₃), known as soda ash, is used in various industrial processes such as glass making, detergent, metallurgy, and water treatment, which is produced from salt brine (NaCl) and limestone (CaCO₃) in the presence of ammonia by the Solvay process. Although the Solvay process is fully optimized, it requires large amounts of energy, generates significant CO₂ emissions, and produces undesirable byproducts. Here we describe a catalytic strategy that can address the energy and environmental challenges facing the Solvay process. The hydrogen-bearing H_xRuO₂ catalyst selectively hydrogenates nitrate to ammonia, facilitating the conversion of CO₂ into sodium bicarbonate (NaHCO₃) through mineralization and yielding valuable ammonium bicarbonate (NH₄HCO₃). We also report on the techno economic analysis and life cycle assessment of the catalytic process compared to the Solvay process via rigorous commercial-scale process design and thereby propose a clear solution to mitigating CO₂ emission, reducing energy consumption, and alleviating the environmental threat without loss of economic feasibility. The newly developed catalytic route might offer a promising alternative process to produce soda ash via an atom economic synthetic route.