有色金属科学与工程2026，Vol.17Issue(2)：203-214,12.DOI:10.13264/j.cnki.ysjskx.2026.02.005
过硫酸铵对微晶石墨混酸提纯的强化作用
Strengthening effect of ammonium persulfate on the mixed-acid purification of microcrystalline graphite
摘要
Abstract
The primary impurity minerals in microcrystalline graphite include quartz,mica,chlorite,and sulfide minerals(such as pyrite).Current acid leaching purification processes face challenges,including the low solubility of impurities and the occurrence of secondary precipitation.In this study,hydrochloric acid(HCl)and hydrofluoric acid(HF)were used as the primary leaching agents,and ammonium persulfate((NH4)2S2O8)was introduced to enhance the oxidative properties of the leaching system,thereby strengthening the purification effect.Acid leaching experiments demonstrated that the fixed carbon content of graphite increased from 98.0%to 98.4%with the addition of ammonium persulfate,indicating a significant improvement in the purification efficiency.Thermodynamic analysis revealed that while pyrite cannot spontaneously react with HF and HCl at ambient temperature,the addition of ammonium persulfate promoted its dissolution.Furthermore,it was found that the reaction of mica and chlorite with HF tended to generate potassium hexafluorosilicate(K2SiF6)precipitates.However,the presence of hydrochloric acid in the mixed acid system effectively suppressed the formation of these precipitates to a certain extent,thereby enhancing the purification efficiency.Structural characterization of the purified graphite indicated that the introduction of ammonium persulfate did not adversely affect the surface morphology or the crystalline structure of the microcrystalline graphite.关键词
微晶石墨/混合酸浸/氧化酸浸/热力学Key words
microcrystalline graphite/mixed acid leaching/oxidative acid leaching/thermodynamics分类
矿业与冶金引用本文复制引用
刘梦飞,朱建裕,刘建忠,文中强,陈代雄..过硫酸铵对微晶石墨混酸提纯的强化作用[J].有色金属科学与工程,2026,17(2):203-214,12.基金项目
国家自然科学基金资助项目(42277256),湖南省重点研发项目(2023SK2010) （42277256）
