Leaching behavior and mineralogical evolution of vanadium released from sodium roasted-acid leaching tailing of vanadium slag  

作　　者：Bao Liu Jin Li Qian-qian Ren Shuang Cai Xue Yang Ya-nan Zeng Jun-guo Li 

机构地区：[1]College of Metallurgy and Energy,North China University of Science and Technology,Tangshan,063210,Hebei,China

出　　处：《Journal of Iron and Steel Research International》2022年第5期772-782,共11页

基　　金：supported by the Natural Science Foundation of Hebei Province(Nos.E2020209195,E2021209043,E2020209043),National Natural Science Foundation of China(No.51574108),Tangshan Municipal Project of Science and Technology(No.19150201E);Science and Technology Project of Hebei Education Department(Nos.BJ2020022,BJ2021034).

摘　　要：The sodium roasted-acid leaching tailing(SRALT)of vanadium slag with a certain amount of vanadium exhibits potential environmental risk.To investigate the leaching behavior of vanadium from the SRALT,neutral batch leaching tests were performed.The evolution of vanadium concentration,pH,redox potential(Eh),dissolved oxygen,and conductivity as a function of time was measured.Pourbaix diagrams of V–H2O system with different vanadium concentrations were obtained to identify the ionic speciation of vanadium in leachate.X-ray diffraction,X-ray photoelectron spectroscopy,field emission-scanning electron microscopy,and thermogravimetry–differential scanning calorimetry analysis were conducted to investigate the mineralogical evolution of the SRALT during the leaching process.It was found that the major minerals of the original SRALT are titanomagnetite,spinel,olivine,and augite.The valence states of V existing in the original SRALT are V^(3+)and V^(5+).The pH and Eh values of the obtained leachates are 10.00–10.58 and(−43)–(+67)mV,respectively.In this pH and Eh region,the released vanadium is mainly present as HVO_(4)^(2−).The FeOOH and CaCO_(3)would form during the leaching process.The HVO_(4)^(2−)would be mainly adsorbed by the FeOOH and slightly incorporated into the CaCO_(3),resulting in the decline in the vanadium concentration.The vanadium concentration above 27 mg L^(−1)and the dissolved oxygen value below 5.0 mg L^(−1)can be obtained after a short leaching period.As a V(V)-releasing and oxygen-depleting substance,the leaching toxicity of the SRALT should not be ignored.

关 键 词：VANADIUM Vanadium slag TAILING Leaching toxicity Mineralogical analysis 

分 类 号：TF841.3[冶金工程—有色金属冶金]