LDH-PCE对锂渣复合水泥流变及水化性能的影响  

Effects of LDH-PCE on Rheological and Hydration Properties of Lithium Slag Composite Cement

作　　者：陈娟 何燕 Chen Juan;He Yan(School of Civil Engineering,Suzhou University of Science and Technology,Suzhou,Jiangsu 215011)

机构地区：[1]苏州科技大学土木工程学院,江苏苏州215011

出　　处：《非金属矿》2025年第1期54-57,73,共5页Non-Metallic Mines

基　　金：国家自然科学基金(51808369);江苏省研究生科研与实践创新计划项目(SJCX23-1722)。

摘　　要：为改善锂渣复合水泥的早期性能,通过两步法制备了丝瓜络状Mg/Al-CO_(3)LDH(层状双金属氢氧化物),采用聚羧酸减水剂(PCE)对LDH进行表面修饰,并将LDH-PCE应用于掺20%锂渣复合水泥中。探究了LDH-PCE对掺20%锂渣(LS)复合水泥的流变性能及水化性能的影响。结果表明,LDH-PCE可显著改善锂渣复合水泥浆体的流变性,缩短初凝时间,提高强度,促进水化放热并缩短水化诱导期。锂渣复合水泥浆体的剪切应力和黏度随着LDH-PCE掺量的增加而逐渐降低。其中,LDH-PCE掺量为2%使3 d、7 d和28 d抗压强度分别提高了17.2%、7.8%和7.5%;LDH-PCE掺量为1%使初凝时间缩短了32 min,水化诱导期缩短2.070 h;LDH-PCE掺量为1.5%使72 h累计放热量增加了18.56 J/g。这是因为LDH-PCE为锂渣复合水泥水化提供成核位点,提高水化速率,促进水化产物Ca(OH)2生成。In order to improve early properties of lithium slag(LS)composite cement,the loofah-shaped Mg/Al-CO_(3)LDH was prepared by two-step method.The surface of LDH was modified by polycarboxylic acid superplasticizer(PCE),and LDH-PCE was applied to the composite cement mixed with 20%LS.The effects of LDH-PCE on rheological properties and hydration properties of 20%LS composite cement were investigated.The results showed that LDH-PCE significantly improved the rheology of LS composite cement,shortened the initial setting time,enhanced the strength,promoted the hydration heat release and shortened induction period of the hydration.The shear stress and viscosity of LS composite binder decreased gradually with the increase of LDH-PCE.The compressive strength of 3 d,7 d and 28 d was respectively increased by 17.2%,7.8%and 7.5%when the addition of LDH-PCE was 2%.1%LDH-PCE shortened the initial setting time was 32 min,and shortened the hydration induction period by 2.070 h.The cumulative heat release of LS composite cement increased by 18.56 J/g at 72 h with the addition of 1.5%LDH-PCE.The LDH-PCE provided nucleation sites for the hydration of LS composite cement,which improved the hydration rate,and promoted the formation of early hydration products Ca(OH)2.

关 键 词：LDH-PCE 锂渣复合水泥 流变性 水化性能 

分 类 号：TU528[建筑科学—建筑技术科学] X705[环境科学与工程—环境工程]