在连续流管式反应器中,以H_2O_2为氧化剂,在温度480~550℃、压力32~38MPa及H_2O_2过量100%~270%的条件下,用超临界水氧化(Supercritical water oxidation,简称SCWO)对含对氨基苯酚的模拟废水进行了实验研究。结果表明,采用SCWO法...在连续流管式反应器中,以H_2O_2为氧化剂,在温度480~550℃、压力32~38MPa及H_2O_2过量100%~270%的条件下,用超临界水氧化(Supercritical water oxidation,简称SCWO)对含对氨基苯酚的模拟废水进行了实验研究。结果表明,采用SCWO法能有效去除废水中的含氮有机物对氨基苯酚。升高温度、升高压力和延长停留时间使COD去除率显著提高。在550℃,38MPa,H_2O_2过量190%和停留时间229s时,COD去除率高达98.5%。在此条件下,SCWO总动力学对COD是2.13级,反应的活化能为29.3kJ/mol。展开更多
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
文摘在连续流管式反应器中,以H_2O_2为氧化剂,在温度480~550℃、压力32~38MPa及H_2O_2过量100%~270%的条件下,用超临界水氧化(Supercritical water oxidation,简称SCWO)对含对氨基苯酚的模拟废水进行了实验研究。结果表明,采用SCWO法能有效去除废水中的含氮有机物对氨基苯酚。升高温度、升高压力和延长停留时间使COD去除率显著提高。在550℃,38MPa,H_2O_2过量190%和停留时间229s时,COD去除率高达98.5%。在此条件下,SCWO总动力学对COD是2.13级,反应的活化能为29.3kJ/mol。
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.