文献类型：期刊文献

中文题名：黔北务正道地区富锂铝土矿溶出性能

英文题名：The Digestion Performance of Lithium-Rich Bauxite in the Wuchuan,Zheng'an and Daozhen Area of Northern Guizhou Province

作者：路坊海 庞朋魏 柴洪云 何海军 魏壮强 舒娅

第一作者：路坊海

机构：[1]贵州理工学院材料与能源工程学院,贵阳550025;[2]贵州大学材料与冶金学院,贵阳550025;[3]国家电投集团贵州遵义产业发展有限公司,贵州遵义564300

第一机构：贵州理工学院材料与能源工程学院

年份：2025

期号：11

起止页码：98-105

中文期刊名：有色金属(冶炼部分)

外文期刊名：Nonferrous Metals(Extractive Metallurgy)

收录：;北大核心:【北大核心2023】；

基金：贵州省科技支撑计划项目(黔科合支撑[2023]一般243);贵州理工学院高层次人才科研启动经费项目(XJGC20181010);贵州省高层次创新型人才培养项目(GZSQCC2018002)。

语种：中文

中文关键词：富锂铝土矿;铝;锂;溶出性能;实际溶出率

外文关键词：lithium-rich bauxite;aluminum;lithium;digestion performance;actual digestion rate

摘要：黔北务川一正安一道真(简称务正道)地区铝土矿资源富锂现象显著,具有较好的锂资源利用潜力。选取务正道地区代表性大型矿床瓦厂坪铝土矿开展富锂铝土矿中铝锂溶出性能研究,所取铝土矿样品Al_(2)O_(3)、SiO_(2)和SO_(3)含量分别为60.66%、10.90%和8.23%,铝硅比为5.57,属于高硫型中低铝硅比铝土矿,锂含量为337μg/g,主要是以类质同象的形式存在于绿泥石黏土矿物中。研究结果表明,原矿最适宜溶出条件为:苛性碱浓度246 g/L、溶出温度255℃、溶出时间45 min、石灰添加量12%、固液比1∶3 g/L,Al_(2)O_(3)实际溶出率为79.65%,Li实际溶出率为71.23%。采用焙烧工艺对铝土矿原矿进行脱硫活化,在原矿最适宜条件下进行溶出试验,活化后矿石中Al2O3实际溶出率80.93%,Li实际溶出率81.29%,整体溶出性能优于原矿,说明矿石经焙烧后,硫化物和有机物含量降低,矿石晶体结构被破坏,有效提高了矿石的溶出性能。热力学数据计算表明,Al_(2)O_(3)和Li_(2)O与NaOH在255℃(528 K)时反应吉布斯自由能分别为-190.05、-72.53 kJ/mol。采用收缩未反应模型进行反应动力学研究,结果表明,溶出温度在255℃时,Al2O3的溶出反应属于边界层传质控制,速率常数为0.0036 min^(-1);Li的溶出反应属于化学反应控制,速率常数为0.00815 min^(-1)。
Lithium is recognized as a strategic critical metal,yet China's lithium supply remains heavily importdependent due to multifaceted constraints.In the Wuchuan-Zheng'an-Daozhen area(abbreviated as Wuzhengdao)of northern Guizhou Province,a pronounced lithium enrichment has been identified within bauxite deposits,exhibiting an average lithium concentration of 756μg/g,2.5 times higher than the national average for Chinese bauxite(306.5μg/g).This region contains proven bauxite reserves of 700 million metric tons,with estimated prospective reserves reaching approximately 980 million metric tons.The associated lithium oxide(Li_(2)O)resources are quantified at 1.82 million metric tons,demonstrating considerable potential for lithium resource exploitation.This study selects the representative large-scale Wachangping bauxite deposit in the Wuzhengdao area to inveatigate the digestion performance of aluminum and lithium in lithium-rich bauxite.The bauxite sample taken has contents of Al_(2)O_(3),SiO_(2) and SO_(3) of 60.66%,10.90% and 8.23% respectively,with an Al/Si ratio of 5.57,which belongs to highsulfur type bauxite with medium and low Al/Si ratio.The lithium content is 337μg/g.The XRD analysis shows that the main minerals are boehmite,SiO_(2) and Fe_(2)O_(3),and lithium exists in the form of isomorphism in chlorite clay minerals.The digestion experiments show that the actual digestion rates of Al_(2)O_(3) and Li is 79.65% and 71.23% respectively under the most suitable digestion conditions for the raw ore including dissolution temperature of 255℃,caustic alkali concentration of 246 g/L,lime dosage of 12%,solid-liquid ratio of 1∶3 g/L,and dissolution time of 45 minutes.Under these conditions,the main phases of the digested red mud are Na_(2)O·Al_(2)O_(3)·SiO_(2)·nH_(2)O and Fe_(2)O_(3),and no characteristic peak of boehmite is found.The SEM microstructural analysis reveals morphological alterations in the red mud,including internal pore formation due to mineral dissolution,indicating thorough extraction of Al_(2)O_(3) and Li2O.Desulfurization treatment of the raw ore was carried out by roasting method.The digestion experiment was carried out under the most suitable digestion conditions.The experimental results show that after activation,the actual digestion rate of Al_(2)O_(3) and Li in roasted ore is 80.93% and 81.29% respectively.The overall digestion performance is better than that of the raw ore,indicating that the sulfur and organic matter contents in the ore are reduced after roasting,and the crystal structure of the ore is destroyed.Thermodynamic data calculations show that the Gibbs free energy of the reactions of Al_(2)O_(3) and Li_(2)O with NaOH at 255℃(528 K)is-190.05 kJ/mol and-72.53 kJ/mol,respectively.The reaction kinetics was studied using the unreacted shrinking core model.The results show that at dissolution temperature of 255℃,the digestion reaction of Al_(2)O_(3) is controlled by boundary layer mass transfer,with a rate constant of 0.0036 min^(-1).The digestion reaction of Li is controlled by chemical reaction,with a rate constant of 0.00815 min^(-1).