Inorganic Chemicals Industry >
Preparation of α-hemihydrate gypsum in Mg-Na mixed salt solution system under atmospheric pressure
Received date: 2023-03-06
Online published: 2023-11-16
The species and concentration of salt solution are the key factors of the preparation process of α-hemihydrate gypsum in the atmospheric salt solution method.With Mg（NO3）2 as main composition，three kinds of mixed salt solution，including Mg（NO3）2-NaCl、Mg（NO3）2-Na2SO4 and Mg（NO3）2-NaNO3，were employed to investigate the crystal transformation from dihydrate gypsum to α-hemihydrate gypsum，and the effects of the concentration of mixed salts，crystal modifier type and dosage on the transformation rate of dihydrate gypsum and crystal morphology were studied in the Mg（NO3）2-NaCl solution.The results showed that in the mixed salt solution of Mg（NO3）2-1%NaCl，the minimum Mg（NO3）2 mass fraction for the complete conversion of gypsum dihydrate to gypsum hemihydrate within 4 h was 27%.As the mass fraction of Mg（NO3）2 increasing from 27% to 36%，the supersaturation of the solution and transformation rate of dihydrate gypsum were increased，and the induction period was decreased from 90 min to 20 min.Using DL-malic acid，maleic acid and 3-nitrophthalic acid as crystal modifiers，the transformation rate of dihydrate gypsum was decreased and the aspect ratio was reduced.When the mass fraction of DL-malic acid was 1%，the absolute dry compressive strength of the α-hemihydrate gypsum was 21.74 MPa.
LI Yunfei , LIU Shuqing , TANG Shengwei , ZHANG Tao . Preparation of α-hemihydrate gypsum in Mg-Na mixed salt solution system under atmospheric pressure[J]. Inorganic Chemicals Industry, 2023 , 55(11) : 100 -106 . DOI: 10.19964/j.issn.1006-4990.2023-0116
| 1 | 逄鲁峰，孙立刚，付鹏，等.一种新型石膏自流平材料的研究与工程应用［J］.新型建筑材料，2021，48（10）：6-10. |
| PANG Lufeng， SUN Ligang， FU Peng，et al.Research and engineering application of a new type of gypsum based self-leveling material［J］.New Building Materials，2021，48（10）：6-10. | |
| 2 | ZAMANIAN A， HESARAKI S， KHORAMI M.Physical and in-vitro biological evaluation of a novel calcium sulfate-apatite nanocomposite［J］.Journal of the Australian Ceramic Society，2010，46（2）：43-47. |
| 3 | LIU Chuanbei， GAO Jianming， TANG Yongbo，et al.Preparation and characterization of gypsum-based materials used for 3D robocasting［J］.Journal of Materials Science，2018，53（24）：16415-16422. |
| 4 | WU Xiaoqin， WU Zhongbiao.Modification of FGD gypsum in hydrothermal mixed salt solution［J］.Journal of Environmental Sciences（China），2006，18（1）：170-175. |
| 5 | 胡成，向玮衡，陈平，等.丁二酸对水热合成α-半水脱硫石膏微晶形貌及力学强度的影响［J］.无机盐工业，2021，53（4）：76-80. |
| HU Cheng， XIANG Weiheng， CHEN Ping，et al.Effects of succinic acid on crystallite morphology and mechanical strength of α-hemihydrate desulfurized gypsum synthesized by hydrothermal method［J］.Inorganic Chemicals Industry，2021，53（4）：76-80. | |
| 6 | 江瀚宁，李玉平，王志云，等.硫酸铝、草酸钾及其共混物对α-半水石膏制备及性能的影响［J］.无机盐工业，2022，54（10）：121-126. |
| JIANG Hanning， LI Yuping， WANG Zhiyun，et al.Effect of potassium oxalate and aluminum sulfate and their compounds on preparation and properties of α-hemihydrate gypsum［J］.Inorganic Che-micals Industry，2022，54（10）：121-126. | |
| 7 | REIGL S， VAN DRIESSCHE A E S， MEHRINGER J，et al.Revisiting the roles of salinity，temperature and water activity in phase selection during calcium sulfate precipitation［J］.CrystEngComm，2022，24（8）：1529-1536. |
| 8 | LIU Tianjie， FAN Hao， XU Yanxia，et al.Effects of metal ions on the morphology of calcium sulfate hemihydrate whiskers by hydrothermal method［J］.Frontiers of Chemical Science and Engineering，2017，11（4）：545-553. |
| 9 | YANG Baojun， DONG Yinzhe， WANG Bainian，et al.A mild alcohol-salt route to synthesize α-hemihydrate gypsum microrods from flue gas desulfurization gypsum in large scale［J］.Materials Research Express，2019，6（4）：045507. |
| 10 | SUKIMOTO S， HARA N， MUKAIYAMA H.Effects of salts on the formation of α-calcium sulfate hemihydrates in aqueous salts solution under the atmospheric pressure［J］.Gypsum & Lime，1985，1985（199）：363-370. |
| 11 | CHEN Xuemei， GAO Jianming， WU Ye，et al.Preparation of CSHW with flue gas desulfurization gypsum［J］.Materials，2022，15（7）：2691. |
| 12 | 杨后文，刘丰，江郡，等.常压水热法制备半水脱硫石膏的工艺因素研究［J］.矿产综合利用，2021（1）：140-143，198. |
| YANG Houwen， LIU Feng， JIANG Jun，et al.Research on process condition on the preparation of hemihydrate desulfurization gypsum with hydrothermal method under atmospheric pressure［J］.Multipurpose Utilization of Mineral Resources，2021（1）：140-143，198. | |
| 13 | JIANG Guangming， WANG Hao， CHEN Qiaoshan，et al.Preparation of alpha-calcium sulfate hemihydrate from FGD gypsum in chloride-free Ca（NO3）2 solution under mild conditions［J］.Fuel，2016，174：235-241. |
| 14 | 杨润，陈德玉，米阳，等.常压无氯复合盐溶液磷石膏制备α-半水石膏［J］.非金属矿，2019，42（4）：1-5. |
| YANG Run， CHEN Deyu， MI Yang，et al.Preparation of α-semi hydrated gypsum from phosphogypsum in atmospheric pressure chlorine-free complex salt solution［J］.Non-Metallic Mines，2019，42（4）：1-5. | |
| 15 | 李军，胡俊要，王涛，等.一种常压盐溶液法制取α-超高强石膏的方法：中国，107382111B［P］.2020-06-19. |
| 16 | LI Zirui， LIU Yong， XING Dongxian，et al.Effect of maleic acid and pH on the preparation of α-calcium sulfate hemihydrate from phosphogypsum in Mg（NO3）2 solution［J］.Journal of Material Cycles and Waste Management，2022，24（1）：143-154. |
| 17 | 李显波.高强α半水磷石膏晶形调控及水化硬化性能研究［D］.贵阳：贵州大学，2019. |
| LI Xianbo.Crystal morphology control and hydration hardening properties of high strength α-hemihydrate phosphogypsum［D］.Guiyang：Guizhou University，2019. | |
| 18 | GAO Dejun， ZHANG Dian， PENG Yanzhou，et al.Effects of different carboxyl additives on the growth habits of hemihydrate gypsum crystals［J］.Construction and Building Materials，2022，316：126037. |
| 19 | LI Xianbo， ZHANG Qin.Effect of molecular structure of organic acids on the crystal habit of α-CaSO4·0.5H2O from phosphogypsum［J］.Crystals，2020，10（1）：24. |
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