石煤酸浸提钒过程中V、Fe、Al的浸出行为研究

Leaching Behaviour of V,Fe,Al during Vanadium Extraction from Stone Coal by Sufuric Acid Leaching

在热力学计算分析的基础上,对某云母型石煤脱碳样在酸浸提钒过程中V、Fe、Al的浸出行为进行研究。结果表明,在氟化钙—硫酸浸出体系中,含钒矿物白云母溶解的同时,赤铁矿和钾长石等矿物亦会发生溶解反应,硫酸浓度、浸出温度、浸出时间、液固比等参数对V、Fe、Al的浸出率影响有相同趋势,铝浸出率高于钒和铁;酸浸过程中主要矿物溶解的难易顺序为赤铁矿、白云母、钾长石,且赤铁矿达到溶解平衡所需时间较长,而白云母和钾长石可在较短时间内达到溶解平衡;要减少酸浸提钒过程中铁的溶出,可在保证钒浸出率的前提下适当缩短浸出时间。

Leaching behaviours of vanadium,iron and aluminum during vanadium extraction from stone coal were investigated applying decarburization sample of muscovite-type stone coal based on thermodynamics calculation and analysis.The results show that in calcium fluoride and sulfuric acid leaching system,potassium feldspar and hematite would be dissolved accompanied with dissolution of main vanadium-bearing mineral muscovite.The effects of sulfuric acid concentration,leaching temperature,leaching time,and ratio of liquid to solid on leaching rates of vanadium,iron,and aluminum present the same trend.Leaching rate of aluminum is higher than those of vanadium and iron.During vanadium extraction from stone coal decarburization sample,main minerals are sequenced in terms of leaching difficulty as hematite,muscovite,and potassium feldspar.It takes a long time for hematite to reach dissolution balance,while muscovite and potassium feldspar realize dissolution balance in relatively short time.Leaching time can be shortened appropriately on premise of ensuring vanadium leaching to decrease dissolution of iron to the largest extent.