中南大学学报（自然科学版）2025，Vol.56Issue(8)：3117-3125,9.DOI:10.11817/j.issn.1672-7207.2025.08.003
高铬钒渣钠化焙烧中钙改性驱动的钒铬选择性提取
Calcium-modification driven selective extraction of vanadium and chromium in sodium roasting of high-chromium vanadium slag
摘要
Abstract
To address the challenges of stable vanadium-chromium spinel structures in high-chromium vanadium slag and the difficulty in separating co-dissolved vanadium and chromium via traditional sodium roasting processes,a novel calcium-modified sodium roasting strategy was proposed.By introducing CaO to modulate the sodium salt roasting system,the effects of different mass ratios of CaO and Na2CO3 on the speciation and separation efficiency of vanadium and chromium were systematically investigated.The results show that when only Na2CO3 is used as the roasting additive,synchronous leaching of vanadium(91.5％)and chromium(63.2％)are achieved.When the mass ratio of CaO and Na2CO3 is 0.67,the vanadium leaching efficiency remains stable,while the chromium leaching efficiency increases to 73.0％.Calcium ions are combined with silica-alumina impurities to form high-melting-point calcium silicate,releasing free Na+ions within the liquid phase and promoting the deep oxidation of chromium-bearing spinel to soluble sodium chromate(Na2CrO4).When the mass ratio of CaO and Na2CO3 is increased to 1,excess Ca2+induces coordination reconstruction,converting vanadium into insoluble calcium vanadates(e.g.,Ca2V2O7 and NaCaVO4),while chromium remains predominantly leached as soluble Na2CrO4.During the water leaching stage,the vanadium leaching rate is 6.28％,while the chromium leaching rate reaches 72.26％.In the NH4HCO3 leaching stage,vanadium leaching rate is 83.84％,and chromium leaching rate is 13.35％,achieving the selective vanadium-chromium extraction and separation.关键词
高铬钒渣/钠化焙烧/钙改性/钒铬分离/选择性提取/配位重构Key words
high-chromium vanadium slag/sodium roasting/calcium-modified/vanadium chromium separation/selective extraction/coordination reconstruction分类
矿业与冶金引用本文复制引用
赵卫夺,徐颖鹏,李江涛,刘旭恒,赵中伟..高铬钒渣钠化焙烧中钙改性驱动的钒铬选择性提取[J].中南大学学报（自然科学版）,2025,56(8):3117-3125,9.基金项目
国家自然科学基金基础科学中心项目(72088101) （72088101）
国家自然科学基金重大项目(52494945)(Project(72088101)supported by Basic Science Center Project for National Natural Science Foundation of China （52494945）
Project(52494945)supported by Major Program of National Natural Science Foundation of China) （52494945）
