Extraction of valuable metals from Ti-bearing blast furnace slag using ammonium sulfate pressurized pyrolysis−acid leaching processes  

硫酸铵加压热解−酸浸工艺提取含钛高炉渣中有价金属

作　　者：Zhen-zhong BIAN Ya-li FENG Hao-ran LI 边振忠;冯雅丽;李浩然(北京科技大学土木与资源工程学院,北京100083;中国科学院过程工程研究所生化工程国家重点实验室,北京100190)

机构地区：[1]School of Civil and Resource Engineering,University of Science and Technology Beijing,Beijing 100083,China [2]State Key Laboratory of Biochemical Engineering,Institute of Process Engineering,Chinese Academy of Sciences,Beijing 100190,China

出　　处：《Transactions of Nonferrous Metals Society of China》2020年第10期2836-2847,共12页中国有色金属学报（英文版）

基　　金：Project(DY135-B2-15)supported by China Ocean Mineral Resources R&D Association;Project(2015ZX07205-003)supported by Major Science and Technology Program for Water Pollution Control and Treatment,China;Projects(21176242,21176026)supported by the National Natural Science Foundation of China。

摘　　要：A novel method of extracting valuable metals from Ti-bearing blast furnace slag(TBBF slag)via pressure pyrolysis of recyclable ammonium sulfate(AS)−acid leaching process was proposed.The results show that when pressurized roasting at an AS-to-slag mass ratio 3:1 and 370℃for 90 min,the extraction rates of titanium,aluminum and magnesium reached 94.5%,91.9%and 97.4%,respectively.The acid leaching solution was subjected to re-crystallization in a boiling state to obtain a titanium product having a TiO2 content of 94.1%.The above crystallization mother liquor was adjusted to pH=6 and pH≥12.2,respectively,and then qualified Al2O3 and MgO products were obtained.The analysis through XRD and SEM−EDS proves that the main phases in roasted samples were NH4AlSO4,CaSO4 and TiOSO4.The thermodynamic analysis presents that the main minerals of perovskite,spinel and diopside in raw ore could spontaneously react with the intermediate produced by AS under optimal conditions.提出一种硫酸铵(AS)加压热解−酸浸新工艺,从含钛高炉渣中(TBBF)分段回收有价金属。结果表明,当在铵矿比3:1、370℃的条件下热解90 min时,钛、铝和镁的提取率分别为94.5%、91.9%和97.4%。酸浸液在沸腾状态下重结晶除杂可获得TiO2含量为94.1%的钛产品。上述结晶母液分别调节pH=6和pH≥12.2,可获得合格的氧化铝和氧化镁产品。XRD和SEM−EDS分析表明,焙烧样品中主要物相为NH4AlSO4、CaSO4和TiOSO4。热力学分析显示,在最优条件下,原矿中钙钛矿、镁铝尖晶石和透辉石能与AS产生的中间产物自发反应。

关 键 词：Ti-bearing blast furnace slag ammonium sulfate pressurized pyrolysis high value products 

分 类 号：TF82[冶金工程—有色金属冶金]