Controllable Synthesis of Various CaCO₃ Morphologies Based on a CCUS Idea

Abstract

A novel, green, and economic CaCO3 synthesis method using a CO2-storage material (CO2SM) was developed based on the strategy of carbon capture, utilization, and storage (CCUS). In this process, CO2SM was used as both a CO2 source and a crystal modifier to regulate and control the crystallization of CaCO3. 1,4-Butanediol (BDO) and/or 1,2-ethanediamine (EDA) from CO2SM played unexpected roles as a surfactant, structure-directing agent, and/or pH modulator. The effects of CO2SM concentrations, reaction temperatures, and reaction times were systematically investigated. Pure calcite (bundle-like and dumbbell-like) and pure vaterite (oblate spheroid and snowball-like) CaCO3 products were obtained. Moreover, the CO2SM was recycled to prepare same crystal phase CaCO3 upon the addition of an appropriate amount of Ca(OH)2 with 120 g·L–1 CO2SM concentration.