A Green Process for Recovery of H2SO4 and Fe2O3 from FeSO4.7H2O by Modeling Phase Equilirbium of the Fe(II)-SO42--H+-Cl-System
A Green Process for Recovery of H2SO4 and Fe2O3 from FeSO4.7H2O by Modeling Phase Equilirbium of the Fe(II)-SO42--H+-Cl-System
复制标题
通过模拟 Fe(II)-SO42--H -Cl-系统相平衡从 FeSO4.7H2O 中回收 H2SO4 和 Fe2O3 的绿色工艺
DOI：
10.1002/aic.15795
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发表时间：
2017
期刊：
影响因子：
--
通讯作者：
Demopoulos GP
中科院分区：
文献类型：
--
作者：
Zhang Yan;Li Zhibao;Zeng Yan;Demopoulos GP
七水硫酸亚铁（FeSO 4·7 H2O）是硫酸法钛白粉生产过程中产生的主要废弃物，对环境造成了严重的危害。提出了一种新的绿色处理七水硫酸亚铁的工艺，即利用铁源，回收硫酸源作为硫酸。结果表明，向FeSO 4溶液中加入浓HCl，可使FeCl 2·4 H2O结晶析出，然后煅烧生成Fe 2 O3和HCl。通过蒸发FeCl 2·4 H2O饱和滤液获得浓H2SO 4溶液（约65重量%）。为了便于工艺开发和设计，测量了FeCl 2·4 H2O在HCl、H2SO 4和HCl + H2SO 4溶液中的溶解度，并使用混合溶剂电解质模型和电解质NRTL模型对实验数据进行了回归。在预测FeCl 2·4 H2O结晶最佳条件的基础上，对新工艺进行了物料衡算。实验室规模试验得到FeCl 2·4 H2O和Fe 2 O3，单次循环回收率约为70%，表明该工艺可行。© 2017美国化学工程师学会AIChE J，63：4549-4563，2017
Ferrous sulfate heptahydrate FeSO4·7H2O is a major waste produced in titanium dioxide industry by the sulfate process and has caused heavy environmental problem. A new green process for the treatment of FeSO4·7H2O was proposed to make use of iron source and recycle sulfate source as H2SO4. It was found that by adding concentrated HCl to the FeSO4solution, FeCl2·4H2O was crystallized out, which was subsequently calcined to produce Fe2O3and HCl. Concentrated H2SO4solution (about 65 wt %) was obtained by evaporating the FeCl2·4H2O‐saturated filtrate. To facilitate the process development and design, the solubilities of FeCl2·4H2O in HCl, H2SO4, and HCl + H2SO4solutions were measured and the experimental data were regressed with both the mixed‐solvent electrolyte model and the electrolyte NRTL model. On the basis of the prediction of the optimum conditions for the crystallization of FeCl2·4H2O, material balance of the new process was calculated. FeCl2·4H2O and Fe2O3were obtained from a laboratory‐scale test with about 70% recovery of ferrous source for a single cycle, indicating the feasibility of the process. © 2017 American Institute of Chemical EngineersAIChE J, 63: 4549–4563, 2017