The effect of carbon dioxide absorption using buton asphalt residue through carbonation on calcium carbonate precipitated efficiency

Abstract

The study investigated the efficiency of generating precipitated calcium carbonate (PCC) by chemical dissolution and carbonation from extracted natural asphalt solid waste residue. This residue was then further transformed into calcium carbonate through a series of steps involving calcination at a temperature of 900 °C for 5 hours and ammonium salt dissolution. Subsequently, the calcined residue is dissolved in ammonium salt solutions (2M - NH4Cl, and NH4NO3) under a temperature condition of 60°C. Next, CO2 was injected into the solution contained a high concentration of calcium sources under a predetermined pressure. Additionally, the solution’s initial pH changed to 12 to be the ideal degree of alkalinity. A flow rate of 1 L/min of acetic acid as the extracting agent would result in the highest level of carbonation efficiency. This process yielded vaterite calcium carbonate with a purity of 99.4%, as verified through X-ray diffraction (XRD) and Fourier-transform infrared (FTIR) tests. The vaterite of polymorphic calcium carbonate has a spherical morphology, according to studies utilizing scanning electron microscopy (SEM), confirming the morphological structure of calcium carbonate. The study could add knowledge on preparing the wastes into the high value of vaterite with low processing procedures.