溶浸液渗滤速度与其调整

围绕溶浸液在松散矿石堆中渗滤浸出条件下流动速度作了讨论 ,包括浸出动力学条件方程 ,矿石块表面液膜厚度与溶浸液流速的关系 ,溶浸体及其解析方程的建立 ,溶浸区的划分和流速不均匀等问题 ,并以此为基础 ,提出四项有实用价值的实现均匀流速的建议。

Separation of silicon and iron in copper slag by carbothermic reduction-alkaline leaching process

Approximately 2.0-3.0 t of copper slag(CS) containing 35%-45% iron is generated for every ton of copper produced during the pyrometallurgical process from copper concentrate. Therefore, the recovery of iron from CS utilizes a valuable metal and alleviates the environmental stress caused by stockpile. In this paper, a new method has been developed to realize the enrichment of iron in CS through the selective removal of silica. The thermodynamic analyses and experimental results show that the iron in CS can be fully reduced into metallic iron by carbothermic reduction at 1473 K for 60 min. The silica was converted into free quartz solid solution(QSS) and cristobalite solid solution(CSS). QSS and CSS are readily soluble, whereas metallic iron is insoluble, in NaOH solution. Under optimal leaching conditions, a residue containing 87.32% iron is obtained by decreasing the silica content to 6.02% in the reduction roasted product. The zinc content in the residue is less than 0.05%. This study lays the foundation for the development of a new method to comprehensively extract silicon and iron in CS while avoiding the generation of secondary tailing.

Design of the Metal Precursors Molecular Structures in Impregnating Solutions for Preparation of Efficient Ni Mo/Al_2O_3 Hydrodesulfurization Catalysts

The molecular structures of metal precursors in the impregnating solution were designed so as to prepare efficient Ni Mo/Al_2O_3 hydrodesulfurization(HDS) catalysts. At first, five typical impregnating solutions were designed; the existing metal precursors, such as [Mo4(citrate)2O11]^(4-)-like, [P2Mo18O62]^(6-)-like and [P2Mo5O23]^(6-)-like species in the solutions were confirmed by laser Raman spectroscopy(LRS). The UV-Vis spectra results indicated that the solutions containing both phosphoric acid and citric acid could change the existing form of nickel species. Five corresponding Ni Mo/Al_2O_3 catalysts were prepared by the incipient wetness impregnation method. The LRS analysis results of dried catalysts showed that the above metal precursors could be partly retained on alumina support after impregnation and drying, although the interface reaction between different metal precursors and alumina support unavoidably took place. Then the catalysts were sulfided and characterized by N2 physisorption, TEM and XPS analyses. The results showed that different metal precursors in impregnating solution could mainly result in the difference in both the morphology of(Ni)Mo S2 slabs and the promoting effect of Ni species. The catalyst prepared mainly with [P2Mo5O23]^(6-)-like species used as precursors exhibited worse dispersion of(Ni)Mo S2 slabs and lower ratio of Ni–Mo–S active phases than the one with [Mo4(citrate)2O11]^(4-)-like species. Promisingly, the catalyst prepared with co-existing [Mo4(citrate)2O11]^(4-)-like, [P2Mo18O62]^(6-)-like and [P2Mo5O23]^(6-)-like species showed better hydrodesulfurization activity for 4,6-DMDBT thanks to its more well-dispersed Ni–Mo–S active phases.

The preparation of supported ionic liquids (SILs) and their application in rare metals separation

This review summarizes the preparation methods of support ionic liquids （SILs） and their applications in rare metals separation The rare metals separation includes the recovery of high value metal ions and the removal of heavy metal ions from wastewater. SILs can be used as a kind of highly efficient multifunctional separation materials. The preparation methods of SILs include chemical immobilization technique in which ILs moieties are supported on solid supports via covalent bonds and physical immobilization techniques in which ILs are immobilized on solid supports via physical method such as simple im- pregnation, sol-gel method. According to the difference of solid supports, this review summarizes the application of polymer supported ionic liquids （P-SILs）, silica based material supported ionic liquids （SM-SILs） and membrane supported ionic liq- uids （M-SILs） in rare metals separation, P-SILs and SM-SILs prepared by chemical method with N-methylimidazolium group can be used as highly efficient anion exchangers with high thermal stability and good chemical stability for adsorption of Cr（Ⅵ）, Re（Ⅶ）, Ce（Ⅳ）. P-SILs prepared via simple impregnation afforded IL functionalized solvent impregnated resins （SIRs） which showed high separation efficiency and selectivity in the separation of rare earths（Ⅲ） （REs（Ⅲ））. SM-SILs prepared via sol-gel method with IL doped in the support as porogens or extractant show high removal efficiencies and excellent stability for the separation of RE（Ⅲ）, Cr（Ⅲ） and Cr（Ⅵ）. M-SILs with IL as plasticizer or carrier show improved stability, high perme- ability coefficient and good selectivity for Cr（VI） transport. Different supports and different supporting methods were suffi- ciently compared. Based on the different practical application, different forms of SILs can be prepared for separation of rare metals with high separation efficiency and selectivity.