【摘要】 本文以铜冶炼过程所产生的含砷废水为研究对象,研究了Fe/As摩尔比、初始pH值、氧分压、反应时间以及反应温度等宏观技术参数对水热臭葱石沉砷过程及沉砷渣物相转变的影响规律。结果表明:在Fe/As摩尔比1.5、初始pH1.0、反应温度160℃、搅拌转速500 r/min、氧分压0.6 MPa和反应时间3 h的优化技术条件下,砷与铁的沉淀率分别为98.09%和87.64%,获得了纯度较高的臭葱石沉砷渣;沉砷渣中砷、铁及硫的含量分别为22.21%、25.36%及3.34%,其中硫主要以亚稳态铁矾的形式存在;降低Fe/As摩尔比和初始pH值、延长反应时间均有利于亚稳态铁矾的返溶、重结晶,进而形成性质稳定的臭葱石物相。更多还原

【Abstract】 In this paper, the arsenic-containing wastewater produced by the copper smelting process was studied. The effects of macroscopic technical parameters, such as Fe/As molar ratio, initial pH, reaction temperature, oxygen partial pressure and reaction time, on the arsenic precipitate process and the phase transformation of scorodite precipitate were investigated. The experimental results indicate that, under hydrothermal conditions of initial Fe/As molar ratio of 1.5,initial pH of 1, temperature of 160 ℃, agitation speed of 500 r/min, oxygen partial pressure of 0.6 MPa and reaction time of 3 h, the arsenic and iron removal rates are 98.09% and 87.64%, respectively, the contents of As, Fe and S in scorodite precipitate are 22.21%, 25.36% and 3.34%, respectively, and the sulfur is mainly in the form of jarosite. Reducing the Fe/As molar ratio and initial pH, and extending the reaction time are all favorable for re-dissolution of metastable jarosite and recrystallization to form the stable scorodite phase.更多还原