采用沉淀−煅烧法回收盐湖卤水中镁资源制备镁橄榄石耐火材料  

Mg recovery from salt lake brine into forsterite refractory materials via precipitation−calcination process

作　　者：张烨 胡岳华[2] 王丽[2] 孙伟[2] Ye ZHANG;Yue-hua HU;Li WANG;Wei SUN(National Engineering Research Center for Comprehensive Utilization of Salt Lake Resources,School of Chemical Engineering,East China University of Science and Technology,Shanghai 200237,China;Key Laboratory of Hunan Province for Clean and Efficient Utilization of Strategic Calcium-containing Mineral Resources,School of Minerals Processing and Bioengineering,Central South University,Changsha410083,China)

机构地区：[1]华东理工大学化工学院国家盐湖资源综合利用工程技术研究中心,上海200237 [2]中南大学资源加工与生物工程学院战略含钙矿物资源清洁高效利用湖南省重点实验室,长沙410083

出　　处：《Transactions of Nonferrous Metals Society of China》2024年第2期694-708,共15页中国有色金属学报（英文版）

基　　金：supports from the National Natural Science Foundation of China(Nos.52204268,51974365,91962223);the Natural Science Foundation of Hunan Province,China(Nos.2020JJ5747,2020JJ5749);the Innovation-driven Project of Central South University,China(No.2020CX039);the National“111”Project of China(No.B14034);the Key Laboratory of Hunan Province for Clean and Efficient Utilization of Strategic Calcium-containing Mineral Resources,China(No.2018TP1002);the Young Elite Scientists Sponsorship Program by CAST,China(No.2019QNRC001).

摘　　要：通过沉淀−煅烧法研究盐湖锂镁分离和镁资源制备高附加值的镁橄榄石耐火材料。采用Na_(2)SiO_(3)和NaOH组合沉淀剂将盐湖卤水中的锂、镁离子沉淀分离,获得不同MgO/SiO2摩尔比的镁沉淀物。镁沉淀物主要由无定形硅酸镁和氢氧化镁堆积而成,在1400℃条件下的质量残留率均在62%以上。高温烧结实验表明,在Mg/Na_(2)SiO_(3)/NaOH的摩尔比为1:0.6:0.8、烧结温度为1350℃、时间为210 min的条件下,镁沉淀物可制备成性能优良的耐火材料,其耐火度在1800℃以上,抗压强度为190.73 MPa,体积密度为2.53 g/cm^(3),显气孔率为5.94%。所制备的耐火材料主要为镁橄榄石相,含有少量的顽火辉石相。Li/Mg separation and magnesium recovery as a high-value forsterite refractory material from the salt lake were investigated via the precipitation−calcination process.The combined Na_(2)SiO_(3)and NaOH precipitants were applied for Li/Mg precipitation separation from salt lake brine and magnesium precipitates could be produced with various MgO/SiO_(2)molar ratios.It is demonstrated that the magnesium precipitates were mainly composed of accumulative amorphous magnesium silicate and magnesium hydroxide,with more than 62%of mass residual at 1400℃.The high-temperature sintering experiments showed that when the Mg/Na_(2)SiO_(3)/NaOH molar ratio was 1:0.6:0.8,the magnesium precipitates could be prepared into a high-quality refractory material under the conditions of 1350℃and 210 min,with the refractoriness of higher than 1800℃,compressive strength of 190.73 MPa,bulk density of 2.53 g/cm^(3),and apparent porosity of 5.94%.The prepared refractory materials mainly contained forsterite,with a minor enstatite phase.

关 键 词：盐湖卤水 组合沉淀剂 锂镁沉淀分离 镁沉淀物 镁橄榄石耐火材料 

分 类 号：TS396.1[轻工技术与工程] TQ175.713[化学工程—硅酸盐工业]