Efficient, pure, and fast synthesis of Na2CO3 under mild conditions from concentrated biogenic CO2 sources using 50 wt% NaOH

This study presents a novel approach for the capture of high-purity biogenic CO 2 to synthesise sodium carbonate from concentrated NaOH solutions (up to 50 wt.%), which has not been previously reported and supported with experimental evidence before. This strategy enables the direct processing of high-purity CO 2 (>95%) from concentrated biogenic sources, such as those in fermentative industries. A customised gas-liquid mixing reactor overcomes viscosity and precipitation challenges, allowing 97.5% CO 2 capture efficiency and mass transfer coefficients up to 16.13 ±0.30 mm/s (n=3), significantly exceeding conventional NaOH-based systems. The optimised hydrodynamic conditions and thermal enhancement occurred in the 88–91 °C temperature range, leading to the production of Na 2 CO 3 with 99.95% purity that meets commercial dense soda standards, with water as the only by-product. Applied to wine industry fermentation, this process offers a new pathway towards a greener sodium carbonate production, eliminating CaCl 2 waste, and leading to the mitigation of up to -8.54 Mt CO 2 /year.