一水硬铝石的热分解反应动力学

根据一水硬铝石(α-AlOOH)分解前后的X射线衍射(XRD)谱, 判断其热分解后主要生成α-Al2O3. 分别用Coats-Redfern积分法和Kissinger方法处理了不同升温速率下一水硬铝石的差热曲线, 两种方法得到的热分解反应动力学参数非常接近, 计算所得的活化能分别为254.54 kJ/mol和244.08 kJ/mol, 并推断了反应的动力学模型和反应机理. 研究表明一水硬铝石的热分解符合Mample单行法则, 相对应的机理为随机成核和随后增长.     

氯化钠对铝硅矿物浮选的影响及其作用机理

采用季铵盐DTAL作捕收剂,研究了氯化钠对一水硬铝石和叶蜡石浮选的影响及其作用机理.随着氯化钠浓度的增加,叶蜡石的浮选回收率显著提高,而一水硬铝石的可浮性受其影响很小.机理研究表明:氯化钠对一水硬铝石的zeta-电位没有影响,而能显著降低叶蜡石的zeta-电位,增强捕收剂与叶腊石的静电作用,促进捕收剂的吸附而活化其浮选;叶蜡石表面电位的降低是因为氯离子对叶蜡石存在选择性吸附作用并对其结构进行插层,使得叶蜡石的层间距从0.93 nm增大至1.40 nm.溶液化学计算表明:氯化钠改变溶液的离子强度,显著降低了季铵盐阳离子表面活性剂的临界胶束浓度,使得吸附了捕收剂的矿物表面更容易疏水上浮.     

黑钨矿的组成与其可浮性

黑钨矿含Fe、Mn比例不同时,可浮性存在差异,但原因一直不大清楚。本文研究Mn/Fe比不同的黑钨矿的浮选、吸附行为,动电现象以及受活化作用的情况。并用溶液化学平衡计算讨论Mn、Fe离子与药剂作用的差别。捕收剂在黑钨矿上的化学吸附与Mn离子有更为密切的关系,Mn/Fe比较高的黑钨矿吸附捕收剂的能力较大,可浮性较好;Mn~(2+)离子的活化作用比Fe~(2+)离子强。     

稀散金属镓锗在选冶回收过程中的富集行为分析

凡口铅锌矿稀散金属镓锗主要是以类质同像形式存在于闪锌矿中，如何有效地综合回收镓锗是凡口矿建矿以来研究的主要课题之一。针对凡口矿综合回收稀散金属镓锗的历史、现状与进展，重点研究了镓锗在选矿回收和湿法冶炼过程中的富集行为及走向，为开发镓锗综合回收新技术提供理论指导，从而提高企业经济效益。     

黑钨矿螯合剂中性油浮选研究

本文介绍我们最近的研究结果。比较了三种螯合剂+中性油浮选黑钨矿及与萤石、石英浮选分离的效果,特别考察细粒黑钨矿(-10μ)及在金属阳离子存在时的浮选效果,并讨论了药剂用作机理。     

Degradation of Lix984N and its effect on interfacial emulsion

1 INTRODUCTION Interfacial cruds are supposed to be one of the commonest and most troublesome problems emerging out in practice of copper solvent extraction. Generally, interfacial cruds are inhomogeneous oil/water emulsions that consist of organic phase, aqueous phase and solid particles. It can lead to a lot of detrimental effects on plant operations including difficult phase disengagement, contaminated electrolytes, extractant loss, declined product quality and polluted environment. Lo…     

微细粒高岭石在水介质中的聚团行为

通过采用沉降法以及颗粒表面动电位测试，考察了水介质中PH的变化以及阳离子表面活性剂对微细粒高岭石颗粒聚团行为的影响．结果表明：pH〈7时，水介质中高岭石颗粒表现为强烈的聚团行为；pH〉9时，主要以分散为主．阳离子型表面活性剂的加入使颗粒表面动电位增大，显著提高了高岭石的聚团效果．随表面活性剂浓度的增大，高岭石的聚团行为更加显著．pH=7时，烷基伯胺醋酸盐随着碳链的增长，对高岭石的聚团效果减弱；同一浓度下季胺盐的聚团效果优于烷基伯胺盐．     

Growth kinetics of Thiobacillus ferrooxidans in bioelectrochemical cell

Thiobacillus ferrooxidans might be the most important bacteria used in biometallurgy. The foundation way of its growth process is oxidizing ferrous in order to obtain energy needed for metabolism, but the variation of ferrous concentration and mixed potential of the culture media would have crucial effect on the bacteria growth.Based on the characteristics of Thiobacillus ferrooxidans growth and redox potential of ferric and ferrous, an electrochemical cell was designed conventionally to study growth rule and the relationship between redox potential and bacteria growth was built up, and some growth kinetics of Thiobacillus ferrooxidans were elucidated. It demonstrates that the variation of open potential of electrochemical cell ΔE shows the growth tendency of Thiobacillus ferrooxidans, at the initial growth stage, the value of ΔE increases slowly, when at logistic growth stage, it increases drastically, and the growth rate of bacteria is linear with the oxidation rate of ferrous. The bacteria growth kinetics model is proposed using Monod and Michealis-Menten equation, and the kinetics parameters are got. The consistence of the measured and the calculated results proves that it is proper to use the proposed kinetics model and the electrochemical cell method to describe the growth rule of Thiobacillus ferrooxidans.     

Electrochemical flotation of diethyldithiocarbamate-pyrrhotite system

Using sodium diethyldithiocarbamate as a collector the flotation behavior of pyrrhotite was investigated.The relationship between potential and pH range for pyrrhotite flotation was established. The results show that the flotation of pyrrhotite is dependent on pulp potential at certain pH values. Pyrrhotite has good floatability from pH 2 to pH 12, and poor flotability at pH＞12. Cyclic voltammetry and Fourier transform infrared spectrum analysis show that the major adsorption product of DDTC on pyrrhotite is tetraethylthiuram disulfide. The intensity of Fourier transform infrared signals of tetraethylthiuram disulfide adsorbed on pyrrhotite and the anode current of a pyrrhotite electrode and flotation response of pyrrhotite are correlated with pulp potentials.     

Synthesis of γ-alkoxy-propylamines and their collecting properties on aluminosilicate minerals

1　INTRODUCTIONBayerprocessiswidelyusedtotreatthebauxitewithmoleratioofAl2 O3toSiO2 (n (Al) /n (Si) )morethan 8.AlthoughthereareabundantbauxiteresourcesinChina ,mostofthemarediasporicbaux itewithhighaluminumcontent ,butlown(Al) /n(Si) ,usually 5 8[1] .ThistypeofbauxiteisdifficulttobetreateddirectlybytheBayerprocess .Itisthereforehighlydesirabletoincreasen(Al) /n(Si)ofbauxitebyphysicalcleaning[2 ] .Forthisreason ,flotationdesilicate Bayerprocesswasdeveloped[3] .Flotationdesilicationc…