An acidic mixture of sulfuric and fluosilicic acid(H_(2)SO_(4)+H_(2)SiF_(6))was employed as lixiviant to enhance leaching of lithium from lepidolite.The H_(2)SiF_(6) was obtained as a byproduct of anhydrous hydrofluor...An acidic mixture of sulfuric and fluosilicic acid(H_(2)SO_(4)+H_(2)SiF_(6))was employed as lixiviant to enhance leaching of lithium from lepidolite.The H_(2)SiF_(6) was obtained as a byproduct of anhydrous hydrofluoric acid production,aiming to provide HF molecules.It was found that the HF molecules were the main reaction component and played a key role in strengthening the dissolution of lepidolite.Different factors,including mass ratio of ore/H_(2)SO_(4)/H_(2)SiF_(6),concentrations of H_(2)SO_(4) and H_(2)SiF_(6),leaching temperatures(40−80℃)and time(15−75 min),were investigated.Moreover,an efficient tubular reactor was employed to improve this acid leaching system.Under the optimal conditions(ore/H_(2)SO_(4)/H_(2)SiF_(6) mass ratio of 1:0.8:1.6,80 wt.% H_(2)SO_(4),15 wt.% H_(2)SiF_(6),80℃,15 min),97.9% of Li,96.4% of K,97.6% of Rb,96.7% of Cs and 81.4% of Al(mass fraction)were leached.Additionally,a two-step thermal process was proposed to remove fluorine of leaching slurry.This acid treatment using an acidic mixture of H_(2)SO_(4) and H_(2)SiF_(6) in a continuous tubular reactor shows potential as an alternative process to extract lithium from lepidolite.展开更多
基于OBE理念,化工专业英语教学团队确定了课程的教学目标、教学内容,并将教学内容分解为learn to read、read to learn、learn to share、share to learn四部分,在此基础上层层递进,采用词汇拓展、猜词游戏、课堂演讲和视频及案例分析...基于OBE理念,化工专业英语教学团队确定了课程的教学目标、教学内容,并将教学内容分解为learn to read、read to learn、learn to share、share to learn四部分,在此基础上层层递进,采用词汇拓展、猜词游戏、课堂演讲和视频及案例分析等教学手段,实现学生从语言学习向语言应用的转变。教师在课程教学中由传统的授课者转变为教学的引导者和推动者,循序渐进地引导学生由被动学习转变为自主学习,以提高学生专业英语学习的有效性,提升学生的专业素养,扩展其国际视野,从而实现课程教学目标。展开更多
基金the financial supports from Natural Science Foundation of Henan,China(No.212300410278)Henan Provincial Key Research and Development Program,China(No.212102310371)+1 种基金Henan Postdoctoral Foundation,China(No.202002020)China Postdoctoral Science Foundation(No.2020M682353).
文摘An acidic mixture of sulfuric and fluosilicic acid(H_(2)SO_(4)+H_(2)SiF_(6))was employed as lixiviant to enhance leaching of lithium from lepidolite.The H_(2)SiF_(6) was obtained as a byproduct of anhydrous hydrofluoric acid production,aiming to provide HF molecules.It was found that the HF molecules were the main reaction component and played a key role in strengthening the dissolution of lepidolite.Different factors,including mass ratio of ore/H_(2)SO_(4)/H_(2)SiF_(6),concentrations of H_(2)SO_(4) and H_(2)SiF_(6),leaching temperatures(40−80℃)and time(15−75 min),were investigated.Moreover,an efficient tubular reactor was employed to improve this acid leaching system.Under the optimal conditions(ore/H_(2)SO_(4)/H_(2)SiF_(6) mass ratio of 1:0.8:1.6,80 wt.% H_(2)SO_(4),15 wt.% H_(2)SiF_(6),80℃,15 min),97.9% of Li,96.4% of K,97.6% of Rb,96.7% of Cs and 81.4% of Al(mass fraction)were leached.Additionally,a two-step thermal process was proposed to remove fluorine of leaching slurry.This acid treatment using an acidic mixture of H_(2)SO_(4) and H_(2)SiF_(6) in a continuous tubular reactor shows potential as an alternative process to extract lithium from lepidolite.
文摘基于OBE理念,化工专业英语教学团队确定了课程的教学目标、教学内容,并将教学内容分解为learn to read、read to learn、learn to share、share to learn四部分,在此基础上层层递进,采用词汇拓展、猜词游戏、课堂演讲和视频及案例分析等教学手段,实现学生从语言学习向语言应用的转变。教师在课程教学中由传统的授课者转变为教学的引导者和推动者,循序渐进地引导学生由被动学习转变为自主学习,以提高学生专业英语学习的有效性,提升学生的专业素养,扩展其国际视野,从而实现课程教学目标。
