Indonesia has the largest natural asphalt reserves located in Buton Island (Asbuton). Ironically, Indonesia imports significant amount of asphalt due to no useful technology to produce asphalt from the Asbuton. Objective of this research is to produce asphalt by extraction of CaCO3 as Asbuton’s impuritiesusing H2CO3 in brine waterassolvent in a semi batch extraction system.CO2 is dissolved in brine water to produce H2CO3 as solvent. Reaction betweenCaCO3 and H2CO3 produces calcium bicarbonate(Ca(HCO3)2). This bicarbonate is then decomposed toCO2and reinjected into the extract or to construct aCO2cycle in semi batch system. The optimum results obtained at extraction conditions of 2 bars, 85oC, ratio 0.02 g/mL, 0,5M NaCl and 100 minutes of extraction time.Product asphalt contains 55% asphaltand 45% impurities. The asphalt specification is suitable for hot-mix asphalt type5/55and can be applied to the asphalt mixture type ofACPen60.