摘要
磷石膏和脱硫石膏是堆存量最大的工业固废石膏,将其转化为半水石膏作为建筑胶凝材料是最主要的资源化利用途径。采用蒸压法制备α-半水石膏,以磷石膏和脱硫石膏为原料,天然石膏作为对照组,探究了十二烷基苯磺酸钠(SDBS)、硫酸铝[Al_(2)(SO_(4))_(3)]、复合转晶剂CM(硫酸铝、柠檬酸钠)对α-半水石膏晶体形貌的调控作用及其强度的影响。结果表明,于135℃下蒸压5 h,3种石膏均能稳定制备α-半水石膏,3种转晶剂对于半水石膏物相组成无影响,同时0.4%(质量分数)CM能够有效降低晶体的长径比;通过t检验法检测,转晶剂对脱硫石膏、天然石膏制备的α-半水石膏的抗压强度有显著性增强作用,α-半水石膏的抗压强度增加2倍以上,分别为13.59 MPa和17.45 MPa。而转晶剂对以磷石膏为原料制备的α-半水石膏的强度没有明显作用。脱硫石膏和天然石膏在0.4%CM的调控下晶体长径比降低,抗压、抗折强度显著提升,而磷石膏由于其杂质影响,转晶剂的作用效果不明显,研究结果可为工业石膏的工业化生产提供一定的理论指导。
Phosphogypsum and desulfurization gypsum are industrial solid wastes with the largest storage capacity,and transforming them into hemihydrate gypsum as building materials is the best way for resource recycle.Theα-hemihydrates gypsum was obtained by autoclave method from different industrial gypsum including desulfurized gypsum(FGD),phospho⁃gypsum(PG)and natural gypsum(NG)as a control group.The effects of crystal modifiers including sodium dodecyl ben⁃zene sulfonate(SDBS),aluminum sulfate[Al_(2)(SO_(4))_(3)]and compound crystal modifier(CM)on the morphology and strength ofα-hemihydrates gypsum were investigated.The results showed that under autoclaved pressure at 135℃for 5 h,α-hemi⁃hydrate gypsum could be prepared by three types of gypsum stably,three types of crystal modifiers had no impact on the phase composition of hemihydrate gypsum.0.4%CM could reduce the aspect ratio of crystals effectively.Based on T-test,the crystal modifiers had significant enhancing effect on the compression strength ofα-hemihydrate gypsum prepared from FGD and NG,which was increased by more than 2 times to 13.59 MPa and 17.45 MPa,respectively.However,the strength ofα-hemihydrates gypsum prepared by PG had no obvious change by adding crystal modifiers.The results exhibited that 0.4%CM could reduce the aspect ratio of crystals and improved compressive and flexural strength significantly ofα-hemihy⁃drates gypsum prepared from FGD and NG.The crystal modifier had no obvious impact onα-hemihydrates gypsum pre⁃pared from PG due to impurities.The results of the study provided a certain degree of theoretical guidance for the industrial production of different gypsum.
作者
王培雄
龚小梅
丁家琪
曹宏
WANG Peixiong;GONG Xiaomei;DING Jiaqi;CAO Hong(Monitoring and Scientific Research Center of Yangtze River Ecology and Environmient Administration,Ministry of Ecology and Environment,Wuhan 430014,China;Hubei Changjiang New Materials Research and Design Institute Co.,Ltd.,Wuhan 430061,China;School of Materials Science and Engineering,Wuhan University of Engineering,Wuhan 430061,China)
出处
《无机盐工业》
CAS
CSCD
北大核心
2024年第4期112-117,共6页
Inorganic Chemicals Industry
基金
国家重点研发计划项目(2022YFC3203500)。
关键词
磷石膏
脱硫石膏
Α-半水石膏
转晶剂
强度
phosphogypsum
desulfurization gypsum
α-hemihydrates gypsum
crystal modifier
mechanical strength
