Indirect mineral carbonation of natural asphalt extraction solid waste residue via pH and temperature control
Michael Ambarita, Devit Ardiansyah, Wolfgang W. Schmahl, Yustina M. Pusparizkita, Rifky Ismail, J. Jamari, Athanasius Priharyoto Bayuseno
Abstract
This study investigated the recycling of solid waste residues from rock asphalt extraction via 5-hour calcination at 900 °C and indirect carbon mineralization. The calcined powder was first dissolved at 60 °C in 2 M CH3COOH, carbonized in NH4HCO3, and agitated at 1200 rpm in 2 M NaOH for 30 minutes at 30–60 °C and pH 12. The precipitated calcium carbonate (PCC) results are calcite (24.4–56.3 wt.%) and vaterite (75.6–3.7 wt.%), as confirmed by XRD analysis, carbonate FTIR spectra, and SEM images of prismatic calcite and spherical vaterite. This high-value PCC product has potential industrial applications, such as paper and plastics.