Depressing effect of flocculants on molybdenite flotation

The quality of recycled process water is an important issue in the flotation of Cu–Mo ores. Processing of Cu–Mo ores includes two steps: a bulk flotation where molybdenite is recovered together with Cu sulfides, and a subsequent selective flotation step where molybdenite is separated from depressed copper sulfides. Flocculants are usually employed in the middling thickeners in the copper plant, and in the Cu–Mo bulk concentrate ahead of the molybdenite plant. However, the floatability of molybdenite, similarly to other naturally hydrophobic minerals, is highly sensitive to the presence of both natural and synthetic polymers. In this work flotation tests demonstrate that conventional flocculants, high-molecular weight anionic polyacrylamides (PAM), are strong molybdenite depressants. Low-molecular weight shear degraded polyacrylamides in spite of losing flocculation efficiency maintain depressing ability for molybdenite. Also a non-ionic flocculant, polyethylene oxide (PEO), has been studied in this project. Our results indicate that PEO is an efficient flocculant for molybdenite suspensions in a wide pH range. However, similarly to polyacrylamides, the PEO flocculant also depresses molybdenite flotation.     

粤东金坑锡铜多金属矿区花岗岩锆石U-Pb年龄和辉钼矿Re-Os年龄及其地质意义

广东揭西县金坑铜锡多金属矿床位于粤东地区西北部莲花山断裂带南西段,是粤东锡铜多金属成矿带近年来发现的一处中—大型铜锡铅锌多金属矿床。采用LA-ICP-MS锆石U-Pb法和辉钼矿Re-Os法对矿区与成矿有关的细粒花岗岩及与锡石共生的辉钼矿进行定年,获得该矿床成岩年龄为(141.0±0.3)Ma,辉钼矿Re-Os同位素年龄为(141.3±1.0)Ma,两者年龄接近,表明成岩成矿关系最为密切。并结合细粒花岗岩主微量元素分析结果表明细粒花岗岩具有高硅富碱特点,属于高分异的I型花岗岩,这种岩浆演化末端产物细粒花岗岩有利于成矿金属元素富集,为本区成矿提供巨量的物源与热源。结合成岩成矿年龄研究与主微量分析,初步认为成矿地质体为早白垩世细粒花岗岩,并探讨该矿床的成因及其成矿动力学背景。     

江西某钨重选尾矿钼回收试验

江西某重选钨尾矿含SiO281.14％、含钼0.022％,钼矿物以辉钼矿为主要,且嵌布特征简单,具有较高的综合回收价值.为了兼顾尾矿作为水泥原料外销的现状,以尽量确保尾矿粒度不明显下降为原则,对试样进行了选钼工艺技术条件研究.试验结果表明,采用两段阶段磨矿、1粗1扫4精l精扫、中矿顺序返回浮选流程处理该试样,最终获得了钼品位为46.520％、回收率为50.95％的钼精矿.     

辉钼矿湿法浸出新工艺研究

在常压下，研究了二氧化锰对辉钼矿的湿法氧化浸出新工艺。该法较现行的高压氧煮、硝酸法具有节能、投资小、效益高等特点。     

The depression behavior and mechanism of tragacanth gum on chalcopyrite during Cu-Mo flotation separation

In this work, tragacanth gum (TG), a nontoxic and environmental friendly organic polymer, was used to replace the traditional inorganic depressants of chalcopyrite during the flotation separation of copper-molybdenum sulfides. The single mineral flotation and artificial mixed minerals flotation experiments were conducted to investigate the effect of TG on flotation separation behaviour of molybdenite and chalcopyrite. The TG’s adsorption mechanism on molybdenite and chalcopyrite was investigated by X-ray photoelectron spectroscopy (XPS) and Time-of-flight secondary ion mass spectrometry (ToF-SIMS). The flotation experiment results showed that at pH 3–8, TG had a significant selective depressive effect on chalcopyrite flotation and it was enhanced with increasing TG concentration, but hardly affected the molybdenite flotation. XPS analysis showed that TG was chemically adsorbed on both molybdenite and chalcopyrite surfaces and ToF-SIMS results demonstrated that the interaction of TG and chalcopyrite was stronger than that of TG and molybdenite. Further, XPS narrow scanning analysis suggested that TG might chemisorb onto chalcopyrite via chemical bond between the carboxyl groups and Fe sites on bulk chalcopyrite surface as well as the hydrogen bond between the hydroxyl groups and surface Fe oxides/hydroxides. The strong TG adsorption on chalcopyrite hindered the subsequent adsorption of PBX on chalcopyrite surface, thus chalcopyrite was significantly depressed and Cu-Mo flotation separation was achieved.     

辉钼精矿熔盐氧化工艺研究

对辉钼精矿在Na2CO3-Na2MoO4-Na2SO4和Na2MoO4-Na2SO4体系的熔盐氧化过程进行了研究.结果表明,在控制适当的工艺条件(配料比、温度、鼓风速度和时间等)下,钼的转化率和脱硫率均可达99%以上.对Na2CO3-Na2MoO4-Na2SO4体系,钼精矿中的钼和硫分别以Na2MoO4和Na2SO4形态进入溶液.对Na2MoO4-Na2SO4体系,钼以Na2MoO4形态进入溶液,硫进入气相,烟气中的SO2浓度达5%以上.     

Investigation into the flotation response of refractory molybdenum ore to depressant mixtures:A case study

In this paper, bulk flotation followed by separation was investigated to concentrate purified molybdenite product from Jinduicheng molybdenum ores(Shanxi province, China). The bench scale tests mainly focussed on separation of molybdenite from other sulfide minerals using the new type of depressants.The effect of each single depressant, including organic depressant-modified dextrin(MD), P-Nokes reagent(PN) and sodium trithiocarbonate(ST), and their mixtures on galena, chalcopyrite and other sulfide ores, was examined in turn by changing the concentrations used in cleaner flotation tests. Closed circuit experiments were carried out under the optimal condition and satisfying recovery and grade of molybdenite concentrate could be achieved(86.294% and 53.157%, respectively). A potential reagent regime was developed, with more environmental friendly and more economical advantages due to the introduction of modified dextrin.     

辉钼矿在微波场中的升温特性及焙烧测试

考察了辉钼矿在微波场中的升温行为,探究了物料量、物料厚度以及微波功率对辉钼矿升温行为的影响。研究结果表明,辉钼矿具有良好的微波吸收性能,其升温过程可分为3个阶段;物料在微波场中升温与微波功率呈正比,而与物料厚度和物料量成反比。在本试验范围内,微波功率0.5 k W条件下,18 min后可将130 g辉钼矿加热至800℃。由焙烧产品的表征结果可知,本试验得到了特征良好的焙烧产品;微波氧化焙烧辉钼精矿制备高纯度三氧化钼是可行的。     

提高某难选钼矿回收率的途径

陕西某难选钼矿石氧化率高、泥化严重。采用一粗二扫的浮选流程,用煤油作捕收剂、松醇油作起泡剂,获得含钼７．９３％ 的钼粗精矿,回收率为８２．７６％ 。再在球磨机中加适量水玻璃作分散剂,通过硫化钠诱导浮选,可获得含钼５．３１％ 的粗精矿,回收率为８５．５３％ ,与前者相比回收率提高了２．７７％ 。     

某钼铋硫混合精矿浮选分离试验

某钼铋硫混合精矿品位较低,粒度较粗,-0.074 mm占64%,钼、铋主要以连生体的形式存在。为获得合格的钼、铋精矿,对试样进行了浮选分离试验。结果表明,试样再磨至-0.074 mm占85%后,采用1粗1精2扫钼铋混浮、1粗2精2扫抑铋浮钼流程处理,最终获得钼品位为53.13%、钼回收率为88.95%、含铋1.46%的钼精矿,铋品位为23.68%、铋回收率为80.06%、含钼3.87%的铋精矿,以及硫品位为31.16%、硫回收率为71.98%、含钼0.32%、含铋1.11%的硫精矿。