MgO Doping on the Sintering and Carbonation Properties of Ternesite

作     者：Du, Xiaoyun Chang, Jun 

作者机构：Dalian Univ Technol Sch Infrastruct Engn Dalian 116024 Peoples R China Hainan Univ Sch Civil Engn & Architecture Haikou 570288 Peoples R China 

出 版 物：《ACS SUSTAINABLE CHEMISTRY & ENGINEERING》 (ACS Sustainable Chem. Eng.)

年 卷 期：2025年第13卷第4期

页      面：1689-1707页

核心收录：

学科分类：0817[工学-化学工程与技术] 08[工学] 0703[理学-化学] 

基　　金：National Key Research and Development Program of China [2022YFE0208200] National Key Research and Development Program of China 

主　　题：C5S2$ low carbon cement periclase carbonatable binder crystal structure 

摘      要：Ternesite has been proven to have significant competitiveness as an ultralow lime CO2 sequestration binder. It is worthy of industrial production for CO2 emission reduction in the cement industry. MgO is inevitable in natural limestone, which may change ternesite s sintering and carbonation properties. This study aims to simulate the effect of MgO content on the sintering and carbonation behavior of ternesite. The results show that less than 4% Mg2+ is dissolved in the crystal structure of ternesite by replacing Ca2+ and induces a reduction of cell size. More than 4% MgO will be sintered to form bredigite and merwinite, restraining ternesite content in clinkers. The compressive strength of ternesite clinker compacts is negatively correlated with the MgO doping content. The increase in MgO doping from 0 to 20% resulted in a 68.2% decrease in compressive strength. MgO doping less than or equal to 3% improves the CO2 sequestration capacity of ternesite clinkers by 4.1%;however, more than or equal to 5% will reduce the CO2 sequestration capacity. The analysis of carbonation products showed that MgO reduced the content of aragonite and vaterite and induced the formation of magnesian calcite and monohydrocalcite. The difference in ternesite content, crystal morphology, and carbonation products is the reason for the change in carbonation properties of MgO-doped clinkers.