Density, Refractive Index, Electrical Conductivity, pH, and FT-IR and UV-Vis Spectra of Potassium Carbonate-Potassium Bicarbonate-Water System

Potassium carbonate (K2CO3) solutions are essential absorbents in carbon capture and storage (CCS) and bioenergy with carbon capture and storage (BECCS) processes, forming potassium bicarbonate (KHCO3) when reacting with CO2 and H2O. Optimizing the desorption of CO2 during solvent regeneration is vital for enhancing efficiency and economic viability. These solutions are widely used in chemical engineering, material science, and environmental science, making an understanding of their physicochemical properties crucial. This study explores the properties of K2CO3 (1) + KHCO3 (2) + H2O (3) mixtures, focusing on density, refractive index, electrical conductivity, pH, and spectral analyses (FT-IR and UV-vis). Measurements span K2CO3 solvent strengths from 5 to 30 wt %, temperatures from 293.2 to 353.2 K, and solvent loadings (theta) from 0.0 to 1.0. The mass fraction ranges are omega 1 = 0.0000-0.3000 and omega 2 = 0.0000-0.3968. Results show that the density and refractive index increase with solvent strength, decrease with temperature, and remain stable with loading. Electrical conductivity rises with solvent strength and temperature but decreases with loading, while pH decreases with loading and temperature. This study provides valuable insights into the behavior of electrolyte solutions, offering significant implications for carbon capture technologies and industrial applications.