Development of Low-emission Pyro-hydrolysis Technology for HCl Regeneration from CaCl2 Waste

Hydrochloric acid (HCl) leaching process plays a significant role in energy-critical elements extraction industry. In this thesis, a low-emission process integrating CO2 capture with SiO2-assisted pyro-hydrolysis was developed for regenerating valuable HCl from CaCl2 waste. The feasibility of this process was comprehensive investigated from techno-economic, thermodynamic, and kinetic aspects. To achieve this, both experimental approach and simulation approach including flowsheet simulation, density functional theory calculation, were employed in this thesis. These findings provide valuable support for the advancement of HCl regeneration technology and make a significant contribution to the circular economy and sustainable development of the HCl-based critical elements extraction industry.