School of Metallurgy, Northeastern University, Shenyang, 110819, Liaoning, China.
School of Metallurgy, Northeastern University, Shenyang, 110819, Liaoning, China; Liaoning Key Laboratory for Recycling Science of Metallurgical Resources, Shenyang, 110819, Liaoning, China.
J Environ Manage. 2019 Aug 15;244:119-126. doi: 10.1016/j.jenvman.2019.05.037. Epub 2019 May 18.
Chromium-containing vanadium tailings (CCVT), an industrial waste, were utilized to extract chromium efficiently by soda roasting-water leaching process and for the preparation of highly pure chromium oxide. The effect of extraction of chromium under different roasting and leaching conditions were analyzed using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The maximum chromium extraction rate of 91.51% was obtained when soda (NaCO) and CCVT were mixed in a molar ratio (n (NaCO)/n (CrO)) of 8, roasted at 900 °C and maintained for 120 min. Then, the roasted product was leached in water at 60 °C for 60 min with a liquid-solid mass ratio (L/S) of 10. During soda roasting, the chromium-containing phase (FeCr)O combines with NaCO to form NaCrO, which was then transferred into the leaching liquid, post water leaching. The by-products such as NaFeTiO, NaCaSiO, and NaFeSiO were left in the leaching residue which was called chromium tailings (CT). 87.40% chromium oxide was recovered from the unpurified leaching liquid after reduction and precipitation by adding NaS, followed by roasting the deposit. This process not only relieved the potential threat of the industrial waste CCVT to the environment but also realized the recovery of the valuable element chromium.
含铬钒尾矿（CCVT）是一种工业废料，通过苏打 roasting-water 浸出工艺高效提取铬，并制备高纯氧化铬。采用 X 射线衍射（XRD）和扫描电子显微镜（SEM）分析了不同焙烧和浸出条件下铬的提取效果。当苏打（NaCO）和 CCVT 以摩尔比（n（NaCO）/n（CrO））为 8 混合，在 900°C 下焙烧 120 分钟时，铬的最大提取率为 91.51%。然后，将焙烧产物在 60°C 下用液固质量比（L/S）为 10 的水浸出 60 分钟。在苏打焙烧过程中，含铬相（FeCr）O 与 NaCO 结合形成 NaCrO，然后转移到浸出液中，再经水浸出。副产物如 NaFeTiO、NaCaSiO 和 NaFeSiO 留在浸出渣中，称为铬尾矿（CT）。在添加 NaS 还原沉淀后，从未纯化的浸出液中回收了 87.40%的氧化铬，然后对沉淀物进行焙烧。该工艺不仅缓解了 CCVT 工业废料对环境的潜在威胁，还实现了有价值元素铬的回收。
