摘要
The synthesis of α-calcium sulfate hemihydrate (α-CSH) from flue gas desulfurization (FGD)gypsum is a good way to realize the comprehensive utilization of FGD gypsum. To obtainα-CSH with the satisfactory performances, a facile hydrothermal-aging pretreatment process for FGD gypsum raw materials was proposed, where FGD gypsum was firstly hydrothermally converted to α-CSH whiskers, and α-CSH whiskers were further hydrated to synthesize CaSO4·2H2O (CSD) by aging under the regulation of N,N'-methylenebisacrylamide (MBA). The effects of aging time, MBA addition, aging temperature, and pH on the morphology of the synthesized CSD were investigated. The synthesized CSD crystals exhibit highly uniform prismatic morphology with the length of ca 100μm and the whiteness of 91.56%. The regulation mechanism of MBA was also illustrated. The synthesized CSD crystals with prismatic morphology were further used as raw materials to synthesize the short columnar α-CSH. The absolute dry compressive strength of paste prepared from the short columnar α-CSH is 40.85 MPa, which reaches α40 strength grade.
作者
苏一鑫
GAO Lili
陈学青
LI Zhishui
李雲
CAO Jilin
SU Yixin;GAO Lili;CHEN Xueqing;LI Zhishui;LI Yun;CAO Jilin(Engineering Research Center of Seawater Utilization Technology of Ministry of Education,School of Chemical Engineering and Technology,Hebei University of Technology,Tianjin 300130,China;Heze Center for Disease Control and Prevention,Heze 274010,China;Tianjin Bohua Yongli Chemical Industry Co.,Ltd.,Tianjin 300452,China)
基金
Funded by National Natural Science Foundation of China(No.22008049)
Natural Science Foundation of Hebei Province,China (Nos.B2020202081 and B2018202330)
Key Laboratory of Gas Hydrate,Guangzhou Institute of Energy Conversion,Chinese Academy of Sciences,China (No.E029kf1601)
Research Fund Program of Science and Technology of Colleges and Universities of Hebei Province,China (No.QN2019012)。
