泰国复杂高岭土矿除铁的试验研究

对泰国复杂高岭土矿样的物相分析表明影响其白度的主要杂质为含铁矿物。试验证明,常规处理方法不能达到除杂目,而化学漂白与螯合剂强化漂白的联合处理方法可以除去大部分含铁杂质,得到白度高、铁含量低的高岭土精矿。     

宜昌某高岭土剥片试验

宜昌某高岭土矿高岭土含量虽达95%左右,但-2μm粒级产率仅占30%,且有10%的叠片状未剥离高岭土,层间的着色有机杂质直接煅烧难以高效脱色。为获得高品质高岭土熟料,对试样进行了剥片工艺条件研究,并对剥片前后的高岭土进行了SEM分析和熟料白度研究。结果表明,在磨矿前一次性加入与试样质量比为3%的分散剂六偏磷酸钠,搅拌磨中刚玉质中球(=1.2 mm)与小球(=0.8 mm)的体积比为0.8∶1.5,介质充填率为70%,磨矿浓度为70%,剥片转速为800 r/min,磨矿时间为180 min情况下,剥片产品-2μm粒级产率为96.62%,普遍为表面平滑、颗粒均匀的高岭土单片;剥片前后高岭土熟料的白度分别为76.84%和82.08%,剥片使熟料的白度提高了5.24个百分点。剥片后高岭土的粒度和熟料的白度均达到高档填料的质量要求。     

离心分离高岭土中铁钛杂质

用离心法脱除耒阳高岭土中铁，钛着色杂质的扩大试验表明，采用离心分离方法可有效地除去高岭土中的铁钛杂质，铁脱除率为３５．７％，钛脱除率为５６．４％，从而使高岭土白度显著提高。     

Technological characterization of kaolin tailing from small-scale mining in RN and PB states – Brazil

In small-scale mining in north-eastern Brazil, the exploitation of industrial minerals, where kaolin bearing pegmatites are mined, is common. The mineral processing of kaolin is based in mixer and classification by screen and cyclone. The overflow of cyclone is thickened and filtered by pressure filter. The product is dried for market. This work presents the results of tailings characterization. Mass balance was realized and recuperation of kaolin about 56% was identified. The feed grade of Al₂O₃ in the plant is 21.20%. The kaolin product for market sold by the company presents 37.19% Al₂O₃ and whiteness of 81.9%. The average Al₂O₃ content of the tailing is 15.55%. Minerals identified are feldspar, muscovite, tourmaline, illite and kaolinite. The −325# fraction of the tailings present Al₂O₃ grades with characteristics for market (Al₂O₃-35%) and whiteness of 79.7%. Values from 7 to 34 wt% of this −325# fraction were determined in the tailing samples analyzed; these results validate the feasibility of reprocessing the tailings for using in the ceramic industry.     

某高岭土矿石中黄铁矿的分选试验

某高岭土矿石中高岭石含量为79.82%,黄铁矿含量达18.14%,杂质矿物含量仅2.06%。为消除黄铁矿对高岭土质量的影响,同时使黄铁矿得到综合利用,对该矿石进行了实验室浮硫试验。试验针对矿石中高岭石易泥化且黄铁矿嵌布粒度较细的特点,采用实验室仿闭路磨矿方式对原矿进行细磨,既可将原矿磨至-0.043 mm占95.37%从而使黄铁矿得以充分解离,又可减轻高岭石泥化对浮硫过程形成的干扰;然后以酸化水玻璃为高岭石的分散、抑制剂,以丁黄药为黄铁矿的捕收剂,通过闭路1次粗选、2次精选、2次扫选,获得了硫品位为48.77%、硫回收率为87.30%的高品质硫精矿,而浮硫槽内产品可直接作为高岭土精矿用于低档陶瓷原料。     

萍乡硬质高岭土矿物学特征及插层复合物制备

通过化学分析、岩矿鉴定、红外光谱、热重-差热分析、X射线衍射和扫描电镜分析测试和观察,对江西萍乡某矿煤系硬质高岭土的矿物学特征进行了研究。结果表明：江西萍乡煤系硬质高岭土矿物组成简单,主要由高岭石组成,杂质含量极少,结晶程度高,可用于合成催化剂用分子筛和制备有机物插层等。在此基础上,进行了高岭石-甲酰胺插层复合物制备的试制研究。     

机械动能磨制备硬质高岭土微粉的工艺参数研究

为了避免高岭土在传统的湿法和普通机械磨超细粉碎过程中引入大量其他杂质,从而造成高岭土纯度降低,研究采用绵阳流能粉体设备有限公司的LNI-330A型机械动能磨对高岭土进行超细粉碎。在分级机转速为1 087 r/min,粉碎主机转速为120 m/s,系统风量为5 400 m³/h,二次风量为465 m³/h,主气流流量为3 523 m³/h情况下,最大产量为397 kg/h,激光粒度分析和扫描电镜分析表明,高岭土微粉的d₅₀<4 μm,呈现结构有序和形貌定型化的特征。     

CRIMM型双箱往复式永磁高梯度磁选机研制及应用

介绍了CRIMM型双箱往复式永磁高梯度磁选机的工作原理、结构和技术参数,指出该机可用于非金属矿加工中去除微细粒弱磁性杂质,并已在长石、高岭土、霞石等非金属矿选矿中获得应用,技术经济效果均佳。     

宜昌某鳞片石墨浮选精矿酸浸脱杂试验

宜昌某鳞片石墨浮选精矿碳含量达93.72%,-200目占83.27%,主要杂质成分为石英、高岭石和伊利石。为了获得高纯石墨精矿,采用混合酸对试样进行了酸浸工艺条件研究。结果表明,混合酸和石墨的体积质量比为3∶1,HF与HCl的物质的量之比为1∶4,酸浸温度为40 ℃,酸浸时间为6 h情况下,可获得固定碳含量为99.1%的高纯石墨精矿。石墨精矿的XRD和SEM分析表明,酸浸工艺可高效地溶出试样中的杂质,且不破坏石墨成分和结构,是获取高品质石墨的重要手段。     

Effect of refractory agent on ash fusibility temperatures of briquette

To solve the problem of the low ash fusion point of briquette, this paper reported that the ash fusibility temperatures can be elevated by changing ash ingredients through blending refractory agents in briquette ash, which will create favorable conditions for moving bed continuous gasification of briquette with oxygen-rich air. The effects of Al₂O₃, SiO₂, kaolin, dry powder and bentonite on ash fusibility temperatures were studied, based upon the relationship between briquette ash components and ash fusibility. The results show that the increasing of ash fusibility temperatures by adding the same amount (11%, w) of refractory agents follows the sequence of SiO₂, bentonite, dry powder, kaolin, Al₂O₃, with the softening temperatures being elevated by 37.2, 57.6, 60.4, 82.6 and 104.4 °. With the same ratio of SiO₂/Al₂O₃ in briquette, adding the Al₂O₃ component is more effective than SiO₂ for raising ash fusibility temperatures. In this paper, inexpensive kaolin and bentonite rich in Al₂O₃ are found to be better refractory agents, and the suitable adding quantities are 9% and 11%, respectively.     

煅烧煤系高岭土和硅粉用于混凝土的对比试验

用煅烧煤系高岭土细粉按一定比例等量取代水泥配制C50高性能混凝土,系统研究了硬化混凝土的力学性能和耐久性能。用工程常用的活性掺合料硅粉作平行试验进行对比,探讨煅烧煤系高岭土细粉代替硅粉用作混凝土活性矿物掺合料的可行性。试验结果表明,经700℃热处理得到的煅烧煤系高岭土具有相当高的水化活性,当掺量同为10%时,掺煅烧煤系高岭土混凝土具有良好的力学性能和耐久性能,而且其对混凝土抗折性能的增强效果优于硅粉。     

煅烧高岭土对卤化丁基胶塞胶性能的影响

分别对不同粒径煅烧高岭土填充的卤化丁基橡胶进行了性能研究,由于团聚,胶料的硫化性能和物理力学性能受到了很大影响;改性高岭土在胶料中的分散性可得到明显的改善,采用Si-69改性土的胶料的综合性能最佳;土的用量对胶料的性能也产生很大的影响.     

Process development for impurity removal from a tin gravity concentrate

A new process for the removal of impurities from tin gravity concentrate using flotation has been developed in this work. Removal of zircon, tantalum and columbite from a tin gravity concentrate has been accomplished by direct tin flotation using a mixture of sulphosuccinate collectors modified with fatty alcohol ester sulphate, and depression of impurities using organic acids and sodium silicate. When using this method, more than 90% of the impurities were removed from the gravity concentrate. The concentrate was upgraded from 58% to approximately 90% SnO₂.The major factors affecting selective flotation of tin from tantalum, niobium and zircon were the degree of collector modification, type and amount of depressant, and the flotation pH. The process has been confirmed in a number of continuous batch tests.     

A DFT study on the effect of lattice impurities on the electronic structures and floatability of sphalerite

The electronic structures of bulk sphalerite containing 14 typical kinds of impurities were studied by density-functional theory (DFT). The calculated results show that the presence of Cd, Hg, Ga, Ge, In, Ag, Sn, Pb and Sb could increase the lattice parameter of sphalerite. Ag, Sn, Pb, Sb, Cd and Hg impurities narrowed the band-gap and increased the conductivity of sphalerite. Moreover, Mn, Fe, Ga, In, Sn and Sb impurities changed the semiconductor type of sphalerite from p-type to n-type. All of the impurities except Cd and Hg made the Fermi level shift to higher energy and led to the occurrence of an impurity state in the forbidden band.Analysis of the frontier molecular orbital showed that the impurities Mn, Fe, Cu, Ge, Sn, Pb and Sb contributed greatly to the highest occupied molecular orbital (HOMO) and greatly influence the nucleophilicity of sphalerite. On the other hand, the impurities of Fe, Cu, Co, Ni, Cd and Ga greatly contributed to the lowest unoccupied molecular orbital (LUMO) and greatly affected the electrophilicity of sphalerite. The interactions of O₂ and xanthate with sphalerite are discussed. Results suggest that Mn, Fe, Ni, Cu, Sn and Pb impurities favored the oxidization of sphalerite; however, the impurities of Cd, Hg, Ga and In had the opposite effect. Impurities of Mn, Fe, Co, Ni, Cu, Hg and Pb could enhance the reactivity of xanthate with sphalerite.     

拜耳法生产氧化铝锌杂质的脱除研究现状

铝土矿中的锌杂质会直接影响氧化铝产品的纯度,影响氧化铝的生产指标。由于氢氧化锌为两性物质,所以锌在拜耳法生产系统中主要以ZnO_2~(2-)的形式存在,再加上锌与铝在苛性溶液中有着较为相似的化学行为,这就使得在拜耳液中脱锌极其困难。目前,国内外主要采用添加硫化物的方法除锌,尤其是在配矿时添加高硫铝土矿除锌,这种方法已经成为拜耳法除锌的很好选择。     

我国高岭土开发现状及综合利用进展

高岭土是一种应用广泛的非金属矿产资源。我国是世界上最早发现并利用高岭土的国家，高岭土储量位居世界前列。虽然我国高岭土储量较大，但随着其应用领域的扩展，资源严重紧缺，价格随之上涨，尤其是优质的高端高岭土加工产品还远不能满足市场消费的需求。本文综述了我国高岭土的主要开发现状、综合利用领域发展进展，并对高岭土的开发与利用情况进行了总结，创建高岭土矿产资源开发与利用新理念，不断探索高岭土资源的开发应用方式，提升高岭土利用效率，促进我国经济可持续高质量发展。      

高岭土提纯工艺及其应用研究进展

高岭土是一种重要的非金属矿产资源,具有良好的吸附性、可塑性和稳定性等,被广泛应用于造纸、陶瓷、橡胶和耐火材料等材料制备领域。但我国生产的高岭土产品质量较低,优质高岭土依赖进口,优化及创新高岭土提纯工艺至关重要。系统的介绍了高岭土的重选、磁选、浮选、浸出、化学漂白和焙烧等提纯工艺,以及高岭土、改性高岭土和纳米高岭土的应用研究进展。      

煤系高岭土粒度对煅烧工艺制度的影响

对不同粒度煤系高岭土进行了煅烧试验研究,并探讨了煤系高岭土的煅烧机理,从实践上证明了利用煤系高岭土生产造纸涂料用优质高岭土的可行性,为开发煤系高岭土进行了有益探讨。     

南方某高岭土除铁增白实验

以南方某高岭土为对象,在试样性质研究的基础上,系统考查了pH值、保险粉用量、草酸用量、矿浆浓度、温度等因素对高岭土白度的影响。结果表明:该高岭土属于砂质高岭土,影响白度的矿物主要为赤铁矿、磁铁矿和金红石;在较优的除铁增白实验条件下,获得了Fe₂O₃含量为0.46%,白度为80.82%的高岭土产品;为该高岭土矿的开发利用提供技术支撑。      

Preparation of layered nickel aluminium double hydroxide from waste solution of nickel

The separation of nickel has been carried out from a waste solution containing 3.18 g/L Ni with other impurities such as Fe, Zn, Cu and As. Iron was removed by precipitation and Cu and Zn were removed by solvent extraction using LIX 622N and NaTOPS-99, respectively. After removal of all these impurities nickel was extracted by 1.5 M NaTOPS-99 in two counter-current stages at A:O ratio of 3:1 and the loaded organic was stripped with 30 g/L H₂SO₄ at phase ratio of unity. The strip solution of nickel was treated with Al₂(NO)₃ · 9H₂O for co-precipitation by increasing the pH of solution with 1 M NaOH up to 10. The Ni–Al layered double hydroxide was confirmed through XRD characterization.