T-2K 捕收剂优先浮选永平铜矿石的研究

将T-2K 捕收剂用于永平铜矿石优先浮选工艺, 进行了开路试验研究, 并对丁黄药-丁铵黑药混合浮选工艺及T-2K 全优先浮选工艺进行了比较, 证实了T-2K 捕收剂对铜矿物具有优异的选择性, 能在弱碱性介质中实现铜的优先浮选。用硬软酸碱理论和前线轨道理论解释了T-2K 的高捕收能力和强选择性。     

氧化铝拜尔法浸出浆液中溶解离子对赤泥分离的影响研究

拜耳法溶出浆液中除含大量的苛性碱(Na2Ok137g/L)外,碳酸钠的含量也高达31.63g/L。试验表明,碳酸根、腐植酸根和有机杂质优先附着在溶出矿浆的矿物颗粒表面,影响合成高分子絮凝剂与赤泥的凝聚沉降。研究发现,沉降速度和沉降赤泥底流固含的提高与添加钙离子有关。少量的钙离子(2.7 g/L)可使合成高分子絮凝剂的活性显著提高,钙离子的存在还可降低絮凝剂的阴离子与带负电的颗粒间的静电斥力,使合成高分子絮凝剂更容易与矿物微粒接近。另外,钙离子还可与带负电的矿物微粒结合而成为与负电性的絮凝剂([C2H3COONa]n)相连接的接合点。用合成高分子絮凝剂代替淀粉使用,可使矿浆颗粒表面留下更多的吸附位置,此对腐植酸根等有机杂质的吸附和去除非常有利。     

辛基胍浮选铝硅酸盐矿物的研究

以辛基硫酸胍SAG8为捕收剂,通过浮选实验、Zeta电位和红外光谱测定,研究了SAG8对铝硅酸盐矿物的浮选性能和作用机理.结果表明:在pH为4-12的范围内SAG8对高峰石、叶腊石和伊利石这三种铝硅酸盐都有较好的捕收能力.Zeta电位测得高峰石、伊利石和叶蜡石的等电点分别为3.5、3.0和2.3.矿物与SAG8作用后其表面正电荷密度增加的均不明显.其可能的原因是:胍是有机强碱.当胍分子一个NH2+与矿物表面Si-O-通过静电作用吸附于矿物表面后,由于胍基中还存在一个NH2官能团,它与矿浆中或者矿物表面的OH-发生氢键作用,矿浆表面OH-浓度增加,从而使矿物表面正电荷密度增加不明显矿粒表面荷负电.结合浮选实验、Zeta电位和红外光谱可以推断出矿物与SAG8的作用机理:SAG8阳离子中同时存在阳离子型和分子型两种NH2官能团,使得SAG8阳离子以静电力和氢键两种方式吸附铝硅酸盐矿物表面.其中在酸性介质中,SAG8主要通过静电力方式吸附在铝硅酸盐矿粒表面,而在碱性条件下以静电力和氢键两种方式作用.     

Flotation of aluminosilicate minerals using alkylguanidine collectors

The flotation mechanism of aluminosilicate minerals using alkylguanidine collectors was studied through flotation experiments, Zeta potential measurements and FT-IR spectrum analysis. It is shown that kaolinite, illite and pyrophyllite all exhibit good floatability with alkylguanidines as collectors at pH 4-12. The flotation recoveries rise with the increase of the carbon chain length. Isoelectric point(IEP) is determined to be 3.5, 3.0 and 2.3 for kaolinite, illite and pyrophyllite, respectively. However, it is anomalous that the presence of cationic collectors has less influence on the negatively charged mineral surfaces. It is explained by the special structure of guanidine which is one of the strongest bases, having two -NH2 groups. One of them maybe interacts with minerals by electrostatic forces, and the other maybe forms hydrogen bonding with OH- ions on the aluminosilicate surfaces or in the aqueous solution, increasing the density of negative charge on the aluminosilicate surface and leading unpronounced positive charge to increase on the aluminosilicate. By combining the flotation tests, Zeta potential and FTIR measurements above, the interaction mechanism can be concluded. The simultaneous presence of cationic and neutral amine groups makes it possible for SAG cation to bind on three aluminosilicate minerals by both electrostatic attraction and hydrogen bonding. While in acidic medium, the interaction of the alkylguanidines on the aluminosilicate surfaces is mainly by means of electrostatic force and hydrogen bond; in the alkaline medium, it is by the way of electrostatic effect and hydrogen bond.     

中碱度条件下乙氧羰基硫脲浮选分离铜硫

对乙氧羰基硫脲和丁黄药组合捕收剂方案浮选德兴铜矿进行了小型和工业试验研究.结果表明,与丁黄药单一捕收剂方案相比,组合捕收剂方案可使石灰用量降低2/3,实现铜铁混合精矿在pH值为10.5左右的高效浮选分离,显著提高矿山铜、金和钼的回收率.采用普遍化微扰理论和密度泛函B3PW91/6-31G(D)计算对上述实验结果进行了理论分析.ECTU的反应中心为硫代羰基中的硫原子,ECTU的最高占据分子轨道与次最高占据分子轨道的能量接近,主要由硫代羰基中的硫原子组成.ECTU的最低未占据分子轨道由官能团-O-C(=O)-N-C(=S)-N-中各原子的pz轨道组成,为一大π键,具有强烈接受和分散电子对的能力.ECTU易与表面电子组态为(t2g)6(eg)3Cu(Ⅱ)或t6e4 Cu(Ⅰ)的硫化铜矿物形成正配键和反馈键,而难与表面电子组态为(t2gа)3(egа)2 Fe(Ⅲ)或(t2g)6Fe(Ⅱ)的硫化铁矿物作用.UV和FTIR光谱结果进一步证实了ECTU对铜矿物具有优异的捕收能力,对硫矿物具有较好的选择性.     

十二烷基胍对铝硅矿物的浮选分离

采用含有胍基的长碳链季铵盐作捕收剂,研究-水硬铝石、高岭石、叶腊石和伊利石单矿物的浮选行为、铝硅人工混合矿样的浮选分离以及河南铝土矿的精选.结果表明:在捕收剂用量为2×10-4mol/L条件下,在广泛的pH范围内,十二烷基胍对硅酸盐矿物具有较好的捕收能力,平均浮选回收率可达80%;强碱性条件下,一水硬铝石的浮选回收率从80%急剧下降至20%,与高岭石、叶腊石和伊利石之间形成较大差异:以十二烷基胍为捕收剂可望实现铝硅矿物反浮选分离:实际铝土矿(原矿铝硅比为5.70)经过反浮选脱硅,精矿铝硅比达11.08,铝浮选回收率为75%;与传统的阳离子捕收剂十二胺相比,胍类阳离子捕收剂对硅酸盐矿物浮选能力强、受pH的影响小,是一种新型高效的铝硅矿物浮选分离捕收剂.     

从发明专利看浮选柱的研究与发展

浮选柱的研究与发展已引起世界许多国家的高度重视.本文综合分析了近30年浮选柱发明专利约190篇,从发明专利的角度评述了浮选柱的研究与发展现状,简要介绍了目前受到普遍关注的充填式、Jameson式、旋流一静态微泡以及CPT浮选柱,并侧重介绍了它们的结构、工作原理及性能.     

Synthesis of Chelating Resin PETU and Its Adsorption to Ag(I)

A novel chelating resin (PETU) with thiourea groups in its main chain was synthesized by the reaction of O,O'-butane-1,4-diyl dicarbonisothiocyanatidate and triethylene tetraamine. The adsorption of Ag(I) on PETU was investigated by batch tests. The results showed that adsorption data fitted Boyd's diffusion equation of liquid film and the adsorption was controlled by liquid film diffusion. Under the temperatures between 15～60 ℃, the adsorption capacity decreased with the increase of temperature, and increased with the increase of initial concentration of Ag(I). The experimental data fitted Langmuir and Freundlich equations, and the correlation coefficients for Langmuir equation were between 0.9965～0.9998, and those for Freundlich equation were between 0.8211～0.9810, and increased with the adsorption temperature. △H, △G and △S calculated by thermodynamic formulae were all negative, which meant that the adsorption process was exothermic and spontaneous, and the entropy decreased during the process. XPS results showed that N, S and O atoms were the electron donors to coordinate with Ag.     

用Visual Foxpro语言编程求解范德华方程的根

范德华方程求解真实气体的体积,传统的求解方程的根的方法是试差法,花费大量的时间,且精度达不到要求,改用Visual Foxpro语言进行程序设计以后,难题迎刃而解。     

型煤用添加剂研究的新进展

概述了型煤发展技术、对型煤所用粘结剂进行了综合评述，认为开发多功能复合粘结剂是发展清洁，高效燃烧型煤的技术关键。