碳酸钠和氯化钙对软锰矿阳离子浮选中方解石的抑制作用（英文）

在软锰矿阳离子浮选中添加十二胺,采用浮选实验、红外光谱分析、接触角测量和zeta电位测试等手段研究碳酸钠和氯化钙对方解石矿物的抑制作用。微浮选实验结果表明,这两种抑制剂都能明显地抑制方解石的浮选。而且,碳酸钠作为活化剂,能增加软锰矿的浮选性能。浮选实验和接触角测试结果表明,碳酸钠对方解石的选择性抑制作用要比氯化钙强。Zeta电位和红外光谱分析表明,碳酸钠减少了方解石矿物表面所带的负电荷,从而减少了十二胺在其表面的静电吸附。在pH=7.5,添加2000 g/t十二胺和1500 g/t碳酸钠的浮选条件下,可得到含40%MnO的软锰矿精矿,回收率达71.5%。

表面溶解对从不同脉石矿物中浮选分离钛铁矿的动力学参数的影响（英文）

研究表面酸溶解对钛铁矿(IL)及其常见伴生脉石矿物(包括橄榄石-辉石(Ol-Px)、透闪石-斜绿泥石(Tr-Cch)和石英)浮选动力学的影响。结果表明,通过表面溶解,钛铁矿的吸附速率常数从5.272增大到8.441 mol/(g·min),而Ol-Px、Tr-Cch和石英的吸附速率常数分别从6.332、7.309和7.774mol/(g·min)减小为5.034、6.223和7.371mol/(g·min)。二元混合矿物的浮选实验结果表明,经表面溶解后,从Ol-Px、Tr-Cch和石英中浮选钛铁矿的修正速率常数值分别从36.15、36.52和47.86min^-1增大到41.72、45.78和56.24min^-1,导致从脉石矿物中分离预处理过的钛铁矿过程的动力学选择性指数(SI)增大。ICP-MS分析证实,脉石矿物动力学参数的降低可能是由于其表面Fe^2+、Ca^2+和Mg^2+的去除,导致矿物表面缺乏足够的活性位点与捕集剂组分发生作用。接触角测量结果证实,表面溶解可防止矿物表面形成稳定的疏水层,从而可在矿物和气泡之间发生稳定的附着。一般来说,钛铁矿浮选动力学参数的提高与伴生脉石矿物中的铁含量呈负相关关系。

加热预处理对钛铁矿及其伴生脉石矿物的表面改性:在浮选过程中的应用

通过浮选实验(微量浮选和实验室浮选槽)、XRD、XPS和FT-IR分析以及Zeta电位和接触角测量,研究常规加热预处理对钛铁矿及其伴生脉石矿物表面性质的影响。在600℃、25 min的最佳条件下进行预处理,pH为6.3时钛铁矿的可浮性由73.5%提高到91%。XRD和XPS分析表明,在此预处理条件下,钛铁矿的Fe^(3+)含量提高约16.5%,而没有出现任何相分解和结构变化。FT-IR分析以及接触角和Zeta电位测量结果证明,钛铁矿可浮性的提高是由于捕收剂吸附作用的增强和较难溶的油酸铁疏水层的形成。矿石浮选实验表明,加热预处理使TiO2回收率由65.4%提高到73.7%,而钛铁矿精矿的TiO2含量没有明显变化。

Cyanex 923支撑液膜中锗的迁移:数学建模（英文）

建立一个数学模型,用于监测草酸溶液中锗(IV)穿过含有4种三烷基氧化膦(Cyanex 923)的平板支撑液膜(FSSLM)的促进迁移过程。FSSLM建模是基于由液-液萃取(LLX)模型计算得出的萃取常数(Kext)。LLX模型提供一种可靠的萃取常数计算方法(Kex=2.057×103 L/mol4)。根据萃取常数、Fick定律和扩散原理,利用Matlab软件对FSSLM模型进行求解。该模型预测的总传质系数(Korg)为3.84 cm/s。利用该总传质系数,得出Cyanex 923浓度为0.126、0.252、0.378、0.505、0.631和0.757 mol/L时的扩散系数(Dm)分别为8.50×10^-4、4.30×10^-4、1.87×10^-4、5.87×10^-5、2.57×10^-5和2.09×10^-5cm2/s。结果表明,本研究得出的扩散速率大于大多数类似的FSSLM体系的扩散速率。这些FSSLM体系都含有Cyanex 923,用于迁移各种金属。模型值与实验数据吻合良好,表明该数学模型具有良好的可靠性。

Applied Mineralogical Studies on Iranian Titanium Deposits

Qara-aghaj and Skandian as hard rock titanium deposit and Kahnooj one as a placer deposit were investigated from applied mineralogical point of view. The mineralogical studies were carried out using XRD, XRF, optical microscopy, scanning electron microscopy and microprobe analysis. These studies indicated that ilmenite and magnetite are main valuable minerals in the studied ores. Pyroxene, olivine and plagioclase are the main gangue minerals in Qara-aghaj ore while chlorite and plagioclase are the major gangue minerals in Skandian ore. Plagioclase, clinopyroxene, amphibole, feldspate and some quartz are the important gangue minerals in kahnooj deposit. In all three ores ilmenite is mainly in the form of ilmenite grains but some lamellae of ilmenite with thickness between 0.1 to 20 μm have been occurred as exsolution textures inside magnetite grains, where the magnetite here can be referred to as ilmenomagnetite. In the hard rock ores some fine ilmenites have been disseminated in silicate minerals. The liberation degree of granular ilmenite was determined 150, 140 and 200 μm for Qara-aghaj, Skandian and Kahnooj, respectively. So, only the granular form of ilmenite is recoverable by physical methods. Some sphene and rutile as titanium containing minerals were observed mainly inside ilmenite phase in kahnooj ore. Some fine rutile was also found inside Skandian ilmenite while there were not any other titanium minerals inside Qara-aghaj ilmenite. Apatite is another valuable mineral which was found only in Qara-aghaj ore. Using SEM and microprobe analysis it was found that there are different amounts of exsolved fine lamellae of hematite inside ilmenite in Qara-aghaj and Kahnooj ores while it was not observed in Sckandian one. The average contents of TiO2 in the lattice of Qara-aghaj, Skandian and Kahnooj ilmenite were determined 51.13, 50.9% and 52.02%, respectively. FeO content of ilmenite lattice for all three samples is clearly lower than the theoretical content. This is due to the substitution of Mg and Mn for some Fe2+ ions in the ilmenite lattice. V2O3 content of magnetite lattice is up to 1%. So, magnetite can be a suitable source for production of vanadium as a by-product in all three deposits.

Removal of Ni and Cd Ions from Aqueous Solution Using Iron Dust-zeolite Composite： Analysis by Thermodynamic, Kinetic and Isotherm Studies

To examine the effectiveness of iron dust-zeolite composite as an adsorbent for the removal of heavymetal ions from aqueous solutions, the adsorption isotherms, the kinetic, thermodynamic and optimum conditions,such as initial concentration, pH, contact time, adsorbent dosage and competitive adsorption conditions of heavymetals were investigated. The characterization of the composite was characterized via FTIR, SEM, XRF and XRDmethods. Kinetic results on the removal of heavy metal ions from aqueous solutions have been well described by thepseudo-second-order model. The adsorption data for Cd and Ni ions were fitted well with the Langmuir and Fretm-dlich isotherm models, respectively. The maximum adsorption capacities of iron dust-zeolite for Cd and Ni ions wereequal to 78.125 and 76.33 mg/g, respectively. The thermodynamic parameters such as enthalpy, entropy and freeenergy of adsorption of metal ions were determined. It was found that the process is endothermic, favorable andspontaneous. The competitive adsorption ability of heavy metal ions in the binary system on the composite showedthat Cd ions had a synergistic effect on the adsorotion of Ni and Ni ions had the negative effect on Cd adsorption.