Affiliation:Mineral Processing and Bioengineering, Central South University
Publish a journal:Separation and Purification Technology
Summary: The abundant resource of steel slag makes it an interesting prospect for long-term COstore through mineral carbonization . In this paper, the dissolution of steel slag in acetic acid (HAc) solution and the immobilization of COin in steel slag leachate are investigated to synthesize high-value CaCO. The results showed that the microwave water bath conditions were beneficial for increasing the leaching rate of Ca and Mg elements in steel slag, while the low concentration HAc solution showed high selectivity for Ca+Mg. In microwave-enhanced water bath reactions, the leaching rate and selectivity of Ca+Mg can be increased by increasing the reaction temperature, extending the leaching time, decreasing the concentration of the HAc solution, and increasing the stirring rate. The kinetic parameters of elemental calcium, including the apparent activation energy, were 14.51 kJ⋅mol, indicating control by surface chemical reactions. Finally, by introducing 20% CO into the leachate, high-purity CaCO whiskers could be synthesized at 400 W ultrasonic conditions at a reaction temperature of 70 °C, a reaction time of 15 minutes, and a solution pH of 9.1. This strategy promotes the parallel utilization of thin smoke gases and large quantities of solid steel slag waste, thereby improving the economic and environmental performance of the steel industry.