mineral carbonation, precipitated calcium carbonate, acetic acid, succinic acid, blast furnace slag, calcium succinate
Two organic acids were trialled for the extraction of calcium from steelmaking blast furnace slag for the purpose of precipitated calcium carbonate (PCC) production: succinic and acetic acids. While the leaching performance of succinic acid was superior, carbonation of its leachate did not result in the production of PCC, but rather the precipitation of calcium succinate, and only after the use of pH buffering agents (sodium hydroxide or bicarbonate). In contrast, carbonation of the acetic acid leachate resulted in the production of PCC, also with the aid of buffering agents. This discrepancy highlights the need for a combination of chemical, mineralogical and morphological analytical techniques for the accurate characterization of carbonation precipitates for future publications in this field. Additional effects observed in this study were the low atom-efficiency of the acids for calcium leaching, at ~20–30% of the stoichiometric value, the low extraction selectivity but high carbonation selectivity between calcium and magnesium, and the contamination of the formed PCC’s with small amounts of co-leached aluminium and silicon. Further work is warranted on the purification of this PCC synthesis route.
Faculty of Applied Science & Technology
School of Chemical and Environmental Sciences
Peer Reviewed/Refereed Publication
PGS-D financial support from the Natural Sciences and Engineering Research Council of Canada (NSERC) (PGSD3-388899-2010)
© 2014 Elsevier B.V. All rights reserved.
Original Publication Citation
Santos, R. M., Chiang, Y. W., Elsen, J., & Van Gerven, T. (2014). Distinguishing between carbonate and non-carbonate precipitates from the carbonation of calcium-containing organic acid leachates. Hydrometallurgy, 147-148, 90-94. doi:10.1016/j.hydromet.2014.05.001
Santos, Rafael M.; Chiang, Yi Wai; Elsen, Jan; and Van Gerven, Tom, "Distinguishing Between Carbonate and Non-carbonate Precipitates From the Carbonation of Calcium-containing Organic Acid Leachates" (2014). Faculty Publications and Scholarship. 18.