Improving Hydration Resistance of MgO-CaO Clinkers by Depositing MgO Coating
By carbotherma1 reduction of MgO with black carbon as reduction agent at a high temperature,MgO was deposited on surface MgO-CaO clinker (as coating) to improve the clinkers hydration resistance.In the paper, effect of deposition temperature and holding time on the hydration resistance of the treated MgO-CaO, the deposition mechanism and MgO coating kinetics were investigated with hydration resistance test, X-ray diffractometry (XRD) and scanning electronic microscope (SEM).Results showed MgO coating grew in a 2-D mode on the surface of MgO-CaO particles;the MgO-coated MgO-CaO clinker improved its hydration resistance,and would become stronger when coated at higher deposition temperature and longer holding time.Measurement also found that MgO deposition process varied with deposition temperature: it was mainly a chemical-controlled process at temperature between 1673K-1773K, with an apparent activation energy (AAE) of 9Z8 kJ mol-1;it would change into a diffusion-controlled process when temperature rising to 1 773K-1873K, with apparent activation energy of 19.2 kJ mol-1.
MgO-CaO clinker hydration resistance MgO coating carbothermal reduction deposition mechanism
YIN Hongfeng LI Botao GAO Kui DING Songxiong
College of Materials and Mineral Resources,Xian University of Architecture & Technology,Xian 71005 College of Materials and Mineral Resources,Xian University of Architecture & Technology,Xian 71005
国际会议
西安
英文
1-5
2016-09-20（万方平台首次上网日期，不代表论文的发表时间）