Simultaneous Treatment of Carbon Dioxide and Desalination Brine Using KOH

抄録

This study proposes a simultaneous treatment method for brine waste and CO₂ using KOH as the CO₂ absorbent. The aim is to selectively separate the dominant ions, namely Mg, Ca, and Na, found in desalination by-products and solar sea salt waste. The process begins with the separation of Mg ions based on their solubility equilibrium, induced by the addition of KOH solution. The separated material is then analyzed for purity and utilized as a CO₂ absorbent. Next, the separation of Ca ions is accomplished by introducing K₂CO₃ to the solution after Mg separation, promoting precipitation based on the solubility balance of seawater ions. In this process, K₂CO₃ obtained from the CO₂ absorption process of KOH is utilized. Finally, Na ions are precipitated and separated by the combined addition of K₂CO₃ and CO₂ absorption. Precipitated metal carbonates are subjected to quantitative and qualitative analyses using techniques such as XRD and SEM. Overall, the proposed method offers a promising approach to address the environmental challenges associated with brine waste treatment and CO₂ mitigation. By utilizing KOH as an absorbent and selectively separating key ions, it presents a viable solution for enhancing the industrial applicability of desalination technology.