The current vanadium extraction process from sodium roasted vanadium slag poses risks such as ammonia pollution.This study proposes a novel calcium-based vanadium extraction and hydrolysis precipitation process,achiev...The current vanadium extraction process from sodium roasted vanadium slag poses risks such as ammonia pollution.This study proposes a novel calcium-based vanadium extraction and hydrolysis precipitation process,achieving clean and efficient vanadium recovery.The introduction of Ca O facilitates the targeted reconstruction and conversion of vanadium and calcium in the solution,forming acidsoluble calcium vanadate intermediates.Under optimal conditions,n(Ca)/n(V)ratio of 1.75,extraction temperature of 90℃,and extraction time of 90 min,the vanadium extraction ratio reached 99.83%.This process also separates vanadium from sodium and silicon,enabling one-step purification of the vanadium solution.Subsequent sulfuric acid leaching,conducted at p H of 4.0,90℃,and 60 min,achieved a vanadium leaching ratio of 99.72%,further separating vanadium from calcium and other impurities.Finally,the purified vanadium solution underwent hydrolysis precipitation at p H of 2.1 and 95℃for60 min,achieving a precipitation ratio of 98.69%.The calcined product yielded V_(2)O_(5) with a purity of 98.60%.Compared to the conventional sodium roasting—water leaching along with ammonium salt precipitation process,this innovative method eliminates ammonia-nitrogen wastewater emissions.This study provides a foundation for the development of new vanadium extraction technologies from vanadium slag.展开更多
基金financially supported by the National Natural Science Foundation of China(52204309,52174277 and 52374300)Fundamental Funds for the Central Universities(N2425026)Liaoning Province Science and Technology Plan Joint Fund(2023-MSBA-052)。
文摘The current vanadium extraction process from sodium roasted vanadium slag poses risks such as ammonia pollution.This study proposes a novel calcium-based vanadium extraction and hydrolysis precipitation process,achieving clean and efficient vanadium recovery.The introduction of Ca O facilitates the targeted reconstruction and conversion of vanadium and calcium in the solution,forming acidsoluble calcium vanadate intermediates.Under optimal conditions,n(Ca)/n(V)ratio of 1.75,extraction temperature of 90℃,and extraction time of 90 min,the vanadium extraction ratio reached 99.83%.This process also separates vanadium from sodium and silicon,enabling one-step purification of the vanadium solution.Subsequent sulfuric acid leaching,conducted at p H of 4.0,90℃,and 60 min,achieved a vanadium leaching ratio of 99.72%,further separating vanadium from calcium and other impurities.Finally,the purified vanadium solution underwent hydrolysis precipitation at p H of 2.1 and 95℃for60 min,achieving a precipitation ratio of 98.69%.The calcined product yielded V_(2)O_(5) with a purity of 98.60%.Compared to the conventional sodium roasting—water leaching along with ammonium salt precipitation process,this innovative method eliminates ammonia-nitrogen wastewater emissions.This study provides a foundation for the development of new vanadium extraction technologies from vanadium slag.
