从某钽铌尾矿中回收长石和石英的试验研究

针对某钽铌尾矿中石英和长石含量较高的特点。在对矿样进行工艺矿物学分析基础上，制定了在碱性条件下，先脱杂质矿物。再浮云母。后浮长石和石英的综合回收工艺流程。试验得到的长石产品可达到玻璃及陶瓷Ⅱ级原料的质量标准，其矿物回收率约为70％～75％。石英产品可达到硅铁Ⅱ级及玻璃Ⅱ级原料的质量标准，其矿物回收率约为75％～80％。     

The formation of feldspar strontian (SrAl2Si2O8) via ceramic route: Reaction mechanism,kinetics and thermodynamics of the process

The reaction mechanism, the equilibrium composition, the temperature range of stability of formed intermediates as well as the kinetics and thermodynamics of activated state during the formation of monoclinic strontium-aluminum-silicate feldspar stroncian (SrAl₂Si₂O₈) via the ceramic route from the mixture of SrCO₃, Al₂O₃ and SiO₂ is described in this work. Strontian does not appear up to the temperature of 1150 °C and is the only stable phase at the temperature ≥1600 °C. Three independent reactions lead to two parallel reaction pathways, i.e. the formation of strontian from single or binary oxides (1) and with Sr-gehlenite as the intermediate (2). Since the reaction rate constants ratio is higher than one (k₁/k₂>1), the first reaction route is favored according to the Wegscheider principle. The kinetics of chemical reaction of 1.5 order corresponding to the kinetic function F_2/3 ((1−α)^−1/2−1) was determined as the rate determining the mechanism of formation of strontian. The integral and differential methods show that the process requires average apparent activation energy of 229.3 kJ mol⁻¹. The determined average value of frequency factor is 2.1×10⁵ s⁻¹.     

Na-feldspar (F) and kaolinite (K) system at high temperature: Resulting phase composition,micro-structural features and mullite-glass Gibbs energy of formation,as a function of F/K ratio and kaolinite crystallinity

The system Na-feldspar (F) and kaolinite (K) was investigated at temperatures of interest in ceramic applications (1200–1280 °C) to study the effects of F/K ratios by weight and crystallinity degree of kaolinite on the final product, micro-structural features and mullite-glass Gibbs energy of formation (ΔG^eff). Mullite and glass are the dominant phases; in general, the higher the temperature, the larger the former. An F/K increase promotes the formation of glass and secondary mullite, appearing along with the primary one. ΔG^eff was modelled by α(T) × (F/K)² + β(T) × F/K + γ(T), α, β and γ being linear functions of temperature whose coefficients were determined by fitting the ΔG^eff-theoretical to the ΔG^eff-obtained from the measured phase compositions. ΔG^eff is less affected by temperature than by F/K, whose increase shifts equilibrium towards glass phases. The ΔG^eff-curves for ordered and disordered kaolinite intersect one another at F/K ～0.5, a ratio close to that used in industrial practice.     

某复杂多金属矿低尾化综合利用技术研究

矿产资源在选矿过程中产生的大量尾矿,既是资源的浪费,又是环境污染源。因此,开展低尾化乃至无尾化综合利用研究,最大程度提高资源利用率是未来矿产资源开发、利用的必由之路。本文在研究国内某复杂多金属矿综合利用时,通过分析所含矿物的基因属性、赋存状态以及嵌布关系,先后进行了钽铌精矿、方解石精矿、锂精矿、云母精矿、长石精矿、石英精矿共计6个产品的选别回收,实现了除少量泥质、铁屑之外的全产品、无尾化综合利用技术路线,可为以后同类型复杂多金属矿的综合回收提供思路借鉴。     

安徽某地石英砂的加温反浮选试验

研究了温度从15℃升高到50℃时,安徽省某地石英砂矿物的反浮选特性。研究表明在矿浆pH值2-2．5时,温度为45℃,石英表面ζ电位的负值是试验温度范围内的最低值,此时长石的表面ζ电位的负值比在25℃时要大,有利于阳离子捕收剂在长石表面的吸附,从而提高长石与石英的浮选分离效果。     

影响火焰光度法测定长石钾钠含量的因素研究

为提高火焰光度法测定长石中钾钠含量的准确度,以钾长石标准物质为参考,在使用FP6410型火焰光度计对长石中钾钠含量测定过程中,对火焰光度计的模拟量、背景酸种类以及共存离子(Fe3+)浓度3个影响因素进行研究。结果表明,火焰光度计模拟量大小对长石钾钠含量测定基本无影响;以HNO3和H2SO4作背景酸时,测定结果与标准物质含量相比,K2O分别偏高10.4%,283.3%,Na2O分别偏高108.7%、387.8%;外加铁试验表明,长石中含Fe2O33.05%时,使用FP6410型火焰光度计测得的K2O含量,偏低9.38%,而对Na2O测定基本没有影响。     

利用合成沸石母液制取电子级碳酸钾

利用钾长石粉为原料合成13X沸石后的母液,经CO2酸化后除去SiO2-3,得NaHCO3-KHCO3-H2O体系;结晶分离可以制备优级纯Na2CO3,余液经除杂,再次酸化得KHCO3结晶,干燥后制备出K2CO3。测试结果表明,碳酸钾产品达到GB/T1587-2000Ⅱ型技术要求。实验证明了利用合成沸石母液提取电子级碳酸钾的可行性,其中碳酸钠回收率达到79.8%,碳酸钾回收率达到83.0%。     

再论十二胺在长石石英表面的吸附作用机理

本文简要介绍了用x射线光电子能谱(XPS)对十二胺在长石和石英表面的吸附作用机理所进行的研究,发现十二胺在两矿物表面的吸附作用有一定差异,并以XPS角分辨分析法所获得的结果计算了十二胺吸附层厚度。     

A Comparative Study on Curing Characteristics,Mechanical Properties,Swelling Behavior,Thermal Stability,and Morphology of Feldspar and Silica in SMR L Vulcanizates

Abstract

Comparison studies on effects of feldspar and silica (Vulcasil C) as a filler in (SMR L grade natural rubber) vulcanizates on curing characteristics, mechanical properties, swelling behavior, thermal analysis, and morphology were examined. The incorporation of both fillers increases the scorch time, t ₂, and cure time, t ₉₀, of SMR L vulcanizates. At a similar filler loading, feldspar exhibited longer t ₂ and t ₉₀ but lower values of maximum torque, M_HR, and torque difference, M_HR–M_L than did silica-filled SMR L vulcanizates. For mechanical properties, both fillers were found to be effective in enhancing the tensile strength (up to 10 phr), tensile modulus, and hardness of the vulcanizates. However, feldspar-filled SMR L vulcanizates showed lower values of mechanical properties than did silica-filled SMR L vulcanizates. Swelling measurement indicates that swelling percentages of both fillers-filled SMR L vulcanizates decrease with increasing filler loading whereas silica shows a lower swelling percentage than feldspar-filled SMR L vulcanizates. Scanning electron microscopy (SEM) on fracture surface of tensile samples showed poor filler–matrix adhesion for both fillers with increasing filler loading in the vulcanizates. However, feldspar-filled SMR L vulcanizates showed poorer filler–matrix adhesion than did silica-filled SMR L vulcanizates. Thermogravimetric analysis (TGA) results indicate that the feldspar-filled SMR L vulcanizates have higher thermal stability than do silica-filled SMR L vulcanizates.     

用阴阳离子混合捕收剂浮选分离石英-长石

本文主要研究用阴阳离子混合捕收剂优先浮选海砂中长石 ,使石英 长石分离 ,用硫酸代替传统的氢氟酸法 ,获得高质量的石英精矿作为优质玻璃原料。