羟肟酸类捕收剂在浮选中的应用现状及发展前景

羟肟酸是一类选择性能很好的螯合捕收剂，可广泛应用于赤铁矿、钛铁矿、硅孔雀石、锡石、萤石、黄绿石、氟碳铈矿和铌钽矿等多种矿物的浮选。本文从羟肟酸的结构、螯合性能、捕收性能、作用机理等方面对羟肟酸类捕收剂近几年的应用和发展情况进行了总结，并指出了今后的发展方向。     

羟肟酸类捕收剂在稀土选矿中的应用与研究进展

羟肟酸是一类选择性能很好的螯合捕收剂，广泛应用于氟碳铈矿和铌钽矿等稀土矿的浮选，在稀土矿的浮选中具有不可替代的作用。本文分别对烷基羟肟酸、烷基水杨醛肟、水杨羟肟酸、2-羟基-3-萘甲羟肟酸、1-羟基-2-萘甲羟肟酸、N-羟基邻苯二甲酰亚胺六种羟肟酸类捕收剂的结构、合成以及对稀土矿的捕收性能等进行了综述。     

羟肟酸类捕收剂的合成、性质及在稀土矿物浮选中的作用机理

介绍了羟肟酸的合成方法和性质、羟肟酸作为捕收剂浮选稀土矿物的性能及羟肟酸类捕收剂在浮选中的作用机理,研究表明羟肟酸具有良好的选择性能和捕收性能,是稀土矿物的有效捕收剂。     

羟肟酸类捕收剂性质及浮选钨矿物特性

通过对羟肟酸类捕收剂性质和羟肟酸类捕收剂与钨矿物作用特性的描述,表明羟肟酸浮选钨矿物最佳pH在pKa附近,此时药剂吸附量最大,ζ电位更负,羟肟酸与矿物表面金属或金属离子羟基化合物发生螯合反应。同时吸附试验结果表明羟肟酸在钨矿物表面的吸附主要为化学吸附,同时存在不均匀、物理吸附,最终形成多层吸附。     

羟肟酸类捕收剂在稀土矿物浮选中的应用及发展

综述了稀土有效捕收剂羟肟酸的浮选性能及其在稀土矿物浮选中的作用机理,介绍了我国几大稀土矿应用羟肟酸选别稀土矿物的情况,讨论了羟肟酸类捕收剂在稀土矿物浮选中的发展和方向。     

N-烃基酰氨基己基羟肟酸对菱锰矿的浮选性能与吸附机理

以N-苯甲酰氨基己基羟肟酸(NO-6)、N-辛酰氨基己基羟肟酸(NO-8)和N-癸酰氨基己基羟肟酸(NO-10)三种新型的羟肟酸为捕收剂,考察了矿浆p H值、捕收剂用量对菱锰矿浮选回收率的影响。结果表明:NO-8和NO-10捕收剂的浮选性能优于NO-6捕收剂,当矿浆p H值为6~7时,NO-8和NO-10浮选菱锰矿回收率可达到90%以上;矿浆p H值更高时,浮选回收率降低;当捕收剂用量相同时,NO-10对菱锰矿的浮选回收率高于NO-8。采用红外光谱分析、Zeta电位测定和XRD分析研究了NO-8和NO-10捕收剂与菱锰矿的作用机理,结果表明,NO-8和NO-10在菱锰矿表面发生了化学吸附。     

环己羟肟酸的催化合成及其对钨锡矿物的浮选性能研究

针对现有的羟肟酸类捕收剂存在捕收力不足、用量较大等问题,本研究开展环己羟肟酸的合成方法及其对钨锡矿物的浮选性能研究。以环己烷羧酸甲酯、盐酸羟胺和氢氧化钠为原料制备环己羟肟酸,对羟肟化反应的原料配比、反应温度、反应时间和催化剂种类进行了研究。结果表明十二烷基苯磺酸钠具有优良的亲水亲油性能,对环己羟肟酸的催化合成效果最好。浮选对比试验表明,环己羟肟酸对含锡黑白钨混合矿的捕收能力强于苯甲羟肟酸,获得相当浮选指标时,环己羟肟酸药剂用量减少15%以上。     

羟肟酸(钠)浮选氧化铜矿石的几个问题

羟肟酸或羟肟酸盐是一种螯合型氧化矿捕收剂,我国自1967年起,着重研究用来浮选氧化铜矿石,于1973年5月在铜录山矿成功地进行了500(吨/日)的浮选工业试验,获得了满意的技术经济指标。为进一步改善药剂的浮选控制及其贮存条件,我们继续进行了几个有关问題的研究。     

苯甲羟肟酸浮选钛铁矿的作用机理

浮选是回收钛铁矿的有效手段,其中捕收剂起着关键作用。目前对钛铁矿捕收剂的研究主要集中在以油酸、羟肟酸等为代表的捕收剂方面,其中苯甲羟肟酸类捕收剂以其高选择性备受关注,但其在对钛铁矿的浮选作用机理方面的研究甚少。从钛铁矿界面性质研究出发,通过单矿物浮选试验、红外光谱、接触角及动电位测定解释了苯甲羟肟酸与钛铁矿的浮选作用机理。     

重-浮选矿新工艺处理难选钽铌钨矿的试验研究

介绍应用阶段磨矿,阶段选别,浮重结合,粗粒重选,细粒浮选的钽铌钨矿综合回收工艺。采用新型高效螯合捕收剂苯甲羟肟酸与辅助捕收剂FW组合浮选细粒级钽铌钨矿,微细摇床处理浮选精矿,显著提高了细粒级钽铌钨矿回收率。当原矿含Ta2O5 0.015 9%,WO3 0.387%时,试验取得品位Ta2O5 1.058%、WO3 42.01%,回收率Ta2O5 48.27%、WO3 78.03%的钽铌钨混合精矿。     

氧化锌矿浮选工艺及捕收剂研究现状

氧化锌矿的浮选工艺分为硫化-胺浮选法、加温硫化黄药法、脂肪酸直接浮选法、螯合浮选法、絮凝浮选法及其它浮选法等。本文系统介绍了这几种浮选工艺及其捕收剂的研究现状,认为浮选新工艺和新型高效捕收剂是解决氧化锌矿难以回收的关键。     

多硫离子硫化技术及其应用

针对低品位氧化金属矿和含氧盐金属矿浮选,提出了一种多硫离子硫化技术。研究表明：以S2-和S2-为主体的多硫离子硫化剂,在矿浆中对碱金属和碱土金属以外的其他主族金属和副族金属元素,具有比单硫离子更强的氧化和螯合力,进而形成四元环和五元环的多硫离子配合物。这种多硫离子配合物,在酸性、中性或碱性矿浆环境下,紧密附着在目标矿石和矿物表面,形成具有较强疏水性的多硫离子硫化物膨化包层,为高效回收低品位氧化金属矿和含氧盐金属矿创造了必要条件。     

螯合树脂富集I2-CCl4萃取光度法测定矿石中的金

利用NK8310鳌合树脂富集金，用硫脲-盐酸解脱液解脱后，采用I2-CCl4萃取光度法测定矿石中的金．取得了较为满意的结果。     

A study and meta-analysis of lay attributions of cures for overcoming specific psychological problems

1. Lipoic acid is an example of an existing drug whose therapeutic effect has been related to its antioxidant activity. 2. Antioxidant activity is a relative concept: it depends on the kind of oxidative stress and the kind of oxidizable substrate (e.g., DNA, lipid, protein). 3. In vitro, the final antioxidant activity of lipoic acid is determined by its concentration and by its antioxidant properties. Four antioxidant properties of lipoic acid have been studied: its metal chelating capacity, its ability to scavenge reactive oxygen species (ROS), its ability to regenerate endogenous antioxidants and its ability to repair oxidative damage. 4. Dihydrolipoic acid (DHLA), formed by reduction of lipoic acid, has more antioxidant properties than does lipoic acid. Both DHLA and lipoic acid have metal-chelating capacity and scavenge ROS, whereas only DHLA is able to regenerate endogenous antioxidants and to repair oxidative damage. 5. As a metal chelator, lipoic acid was shown to provide antioxidant activity by chelating Fe2+ and Cu2+; DHLA can do so by chelating Cd2+. 6. As scavengers of ROS, lipoic acid and DHLA display antioxidant activity in most experiments, whereas, in particular cases, pro-oxidant activity has been observed. However, lipoic acid can act as an antioxidant against the pro-oxidant activity produced by DHLA. 7. DHLA has the capacity to regenerate the endogenous antioxidants vitamin E, vitamin C and glutathione. 8. DHLA can provide peptide methionine sulfoxide reductase with reducing equivalents. This enhances the repair of oxidatively damaged proteins such as alpha-1 antiprotease. 9. Through the lipoamide dehydrogenase-dependent reduction of lipoic acid, the cell can draw on its NADH pool for antioxidant activity additionally to its NADPH pool, which is usually consumed during oxidative stress. 10. Within drug-related antioxidant pharmacology, lipoic acid is a model compound that enhances understanding of the mode of action of antioxidants in drug therapy.     

巯基乙酸钠选矿机理研究与应用

巯基乙酸钠中两个极性基团一COOH及—SH具有同硫化矿强烈反应的特性，是代替氰化钠抑杂的理想药剂。该药剂同矿物表面作用机理用Gibbs公式解释。钼业公司的成功应用就是验证。     

Thickening and rheological properties of slurries as functions of the oxidized nickel ore composition

The thickening and rheological properties of ore slurries and pulps after autoclave sulfuric acid leaching are analyzed as a function of the phase composition of oxidized nickel ore. Experiments have been carried out with samples of ferrous, silicate and combined ores. The initial concentration of the ore slurries is ～28%. Higher values of thickening properties (thickening rate of 1.3 m/day, thickened layer concentration of 54%) are exhibited by the ferrous ore slurry and the pulp after its leaching (thickening rate of 0.9 m/day, thickened layer concentration of 42%). The thickening rate of silicate ore slurry is 0.15–0.2 m/day, the thickened layer concentration is 40–45%. The thickening properties of the pulp after autoclave sulfuric acid leaching of silicate ore strongly depend on the consumption of sulfuric acid. The thickening properties of combined ore and pulps after its leaching deteriorate with increase in the content of silicon dioxide in the ore. In terms of the rheological properties, all slurries are pseudoplastic systems. Poorly thickening slurries are characterized by a high dynamic yield stress (up to 7 Pa) and apparent plastic and effective viscosities. The effective viscosity at the equivalent shear rate corresponding to the mixer rotation rate in laboratory autoclave reaches 34 × 10^–3 Pa s. Boundary values are determined in rheological constants with regard to the thickening properties. For instance, if the dynamic yield point is <1.0 Pa, the thickening rate increases from 0.2 to 1.3 m/day; if the yield point is >1.0 Pa, the thickening rate decreases from 0.075 m/day to zero. The thickening and rheological properties are found to depend on the particle size of solid phase and its surface properties.