Supercritical antisolvent precipitation of calcium acetate from eggshells

The search for sustainable resources remains a matter of global interest. The presence of calcium in food waste may be a material to be valued. In this paper we show a new way of precipitating calcium acetate, produced from eggshells, using the supercritical antisolvent technique (SAS). It also presents the study of the precipitation efficiency as a function of the experimental conditions that affect the SAS results temperature, pressure, liquid solution concentration and injection flow. It was possible to obtain good results under almost all experimental conditions, highlighting a higher yield for 200 bar pressures and lower solution injection flows. The obtained particles have a rod-like appearance having different sizes depending on the operating conditions. (C) 2020 Elsevier B.V. All rights reserved.