锂渣粉的组成及在水泥浆体中的物理与化学反应特性  

Composition of Lithium Slag Powder and Its Physical and Chemical Reaction Characteristics in Cement Paste

作　　者：李保亮[1] 尤南乔 曹瑞林 霍彬彬 陈春[1] 张亚梅[1] LI Baoliang;YOU Nanqiao;CAO Ruilin;HUO Binbin;CHEN Chun;ZHANG Yamei(Jiangsu Key Laboratory of Construction Materials,School of Materials Science and Engineering,Southeast University,Nanjing 211189,China)

机构地区：[1]东南大学材料科学与工程学院,江苏省土木工程材料重点实验室,南京211189

出　　处：《材料导报》2020年第10期10046-10051,共6页Materials Reports

基　　金：中日政府间科技合作项目(2016YFE0118200);国家自然科学基金(51778132);国家973项目(2015CB655100)。

摘　　要：利用XRF、ICP、XRD、TG/DTG、FTIR、SEM-EDS和氮气吸附等手段,分析了典型锂渣粉的组成及锂渣粉在水泥浆体中的物理与化学反应特性。结果表明:锂渣中含有层块状锂辉石、棒状石膏、多孔状硅藻土、球形锂辉石与饼状碳酸钙等;锂渣属于多孔材料,其孔主要为2~50 nm的中孔,主要由锂辉石、炭黑、硅藻土等引起;锂渣的BET比表面积为P·II52.5水泥的5倍,总孔体积为水泥的4倍,但平均孔径小于水泥;锂辉石、石膏、硅藻土与炭黑等的存在是导致锂渣含水率较高的主要原因;此外,锂渣混凝土需水量大,还与石膏、硫酸钠、碳酸钠和碳酸锂等可与水泥中的铝酸盐矿物反应形成较多钙矾石等有关。锂渣属于酸性渣,掺加到水泥中会降低水泥浆体的碱度;锂渣中影响水泥水化的元素主要为S、Ca、Si、Al和K等,而Li的影响较小;锂渣具有较高活性,不仅与其中的石膏有关,还与硫酸钠、碳酸钠和碳酸锂有关。Composition of lithium slag( LS) powder and its physical and chemical reaction characteristics in cement paste were analyzed by means of XRF,ICP,XRD,TG/DTG,FTIR,SEM-EDS,nitrogen adsorption,etc. The SEM results showed that LS contained layered leached spodumene,rod-like gypsum,porous diatomite,spherical leached spodumene and disk-shaped calcium carbonate. Moreover,LS was a porous material,whose pores were mainly mesopores of 2-50 nm,caused by layered leached spodumene,carbon black,porous diatomite,etc. The specific surface area from BET test and total pore volume in LS were 5 times and 4 times of P·II 52. 5 cement respectively,but the average pore size was smaller than that of cement. Layered leached spodumene,gypsum as well as porous diatomite and carbon black were the main sources of high water content of LS. In addition,the large water demand of LS blended concrete was also related to the fact that gypsum,sodium sulfate,sodium carbonate and lithium carbonate can react with aluminate mineral in cement to form more ettringite,etc. LS is an acid slag which can reduce the alkalinity of cement paste mixed with LS. The main elements in LS affecting cement hydration are S,Ca,Si,Al,K,etc.,while the influence of Li can be neglected. In addition to gypsum,the reason why LS has relatively high activity is also related to sodium sulfate,sodium carbonate and lithium carbonate in LS.

关 键 词：锂渣粉 组成 水泥浆体 形貌 孔 特性 

分 类 号：TU528[建筑科学—建筑技术科学]