Integration of CO2 capture and storage based on pH-swing mineral carbonation using recyclable ammonium salts

The integration of CO2 capture and storage process based on mineral carbonation using recyclable ammonium salts is a new approach to capture carbon dioxide and convert it into mineral carbonates. This process avoids stripping CO2 as pure gas from absorbents and compression of CO2, and therefore reduces energy consumption. The additives used in this process are recyclable ammonium salts, the NH4HSO4 and NH4HCO3. The results from extraction experiments show that NH4HSO4 was able to extract 100% of magnesium from serpentine at 100 degrees C after 3 hours. And the precipitation of hydromagnesite using NH4HCO3 solution is much more effective than using CO2, where the highest magnesium carbonation achieved 96%. Based on the experimental results, this process shows that the process has the potential to be cost-effective. (C) 2011 Published by Elsevier Ltd.