A review of use of metallurgical slag for its carbonation products: processes, crystallization behavior, and application status

In response to the pressing global issue of reducing carbon emissions and the crucial technical challenges of fully utilizing steel slag, researchers have been studying an accelerated carbonation process that entails the carbonation of basic oxides in steel slag to store CO2. However, despite its promising potential, the process has yet to see widespread industrial application. The latest research progress in the area of mineral carbonation processes, both direct and indirect, that are used to capture, utilize, and store carbon in steel slag are summarized. Given the limited scale of steel slag carbonation and the underutilized products that can be derived from it, a new research focus is proposed for examining the regulation of calcium carbonate crystal forms during carbonation using the Ca source in steel slag. Precise control of synthesis variables will help to ensure accurate control of calcium carbonate precipitation in the carbonation process. A summary of the effects of synthesis variables on CaCO3 crystal form and the latest research findings on controlling aragonite morphology are provided. The review is concluded with a discussion of the potential applications and future development prospects of CaCO3 whiskers.

Automated summary

In response to the global issue of reducing carbon emissions and the challenges of utilizing steel slag, researchers have studied an accelerated carbonation process to store CO2. Despite its potential, the process has not been widely applied in industry yet. This review summarizes the latest research progress in mineral carbonation processes and proposes a new research focus on regulating calcium carbonate crystal forms during carbonation using the Ca source in steel slag. The potential applications and future development prospects of CaCO3 whiskers are also discussed.