磨矿介质对长石和石英浮选行为的影响及机理分析

研究了长石和石英在湿式磨矿条件下,分别选用十二胺和油酸钠作为捕收剂,锆球和铁球作为磨矿介质时的浮选行为;并通过检测矿浆中典型金属离子浓度和矿物动电位,借助于矿物表面X-射线光电子能谱(XPS)检测,剖析磨矿介质对矿物浮选影响的机理。研究表明,采用十二胺作为捕收剂时,无论是铁球湿磨还是锆球湿磨,长石的回收率都高于石英;采用油酸钠作为捕收剂时,锆球湿磨长石和石英均不浮,铁球湿磨长石和石英的可浮性存在一定差异。矿浆中典型金属离子浓度、矿物动电位和矿物表面XPS的检测结果表明,锆球湿磨长石和石英矿浆中金属离子浓度高,不利于阴离子捕收剂浮选;铁球湿磨时,长石和石英零电点对应的p H值比锆球湿磨高,在两种矿物表面均检测出铁的羟基络合物,这不利于阳离子捕收剂浮选,而有利于阴离子捕收剂浮选。     

组合捕收剂浮选菱锌矿的分子头基尺寸响应

通过单矿物浮选、动电位测试以及荧光探针检测对比研究了不同头基尺寸捕收剂组合油酸钠/十二胺和油酸钠/溴代十六烷基吡啶在菱锌矿表面的吸附特性及其对矿物浮选行为的影响。单一捕收剂体系浮选试验结果表明,3种捕收剂体系下,随着捕收剂浓度增加,矿物浮选回收率均呈现先增加后下降的趋势,油酸钠、溴代十六烷基吡啶、十二胺分别在pH值为5.8、8.4和10.1处达到最大回收率,3种捕收剂对菱锌矿的捕收能力顺序为油酸钠>溴代十六烷基吡啶>十二胺。混合捕收剂体系中,固定油酸钠浓度为2×10^-4 mol/L,加入适量的十二胺可以大幅促进矿物浮选,而加入溴代十六烷基吡啶几乎没有影响。动电位测试结果表明,在pH=6时经2×10^-4 mol/L油酸钠溶液处理的菱锌矿表面电位为-30.5 mV,随着十二胺用量增加,已吸附油酸钠的菱锌矿表面电位逐渐上升,在十二胺浓度2×10^-4 mol/L时其表面动电位升高到接近菱锌矿在纯水中的动电位值22.3 mV,这是由于十二胺阳离子在已吸附了油酸钠阴离子的菱锌矿表面发生吸附;而溴代十六烷基吡啶的加入对菱锌...     

石英与长石在中性介质中的浮选分离研究

用阴离子捕收剂油酸钠和阳离子捕收剂十二胺作为浮选捕收剂,在近中性条件下浮选分离长石和石英,研究了浮选条件对分离效果的影响以及捕收剂在矿物表面的吸附行为。实验结果表明,最佳浮选条件为:浮选温度为40℃、p H值为8、阴离子捕收剂浓度为3×10-3 mol/L、阳离子捕收剂浓度为6.25×10-4 mol/L。在最佳浮选条件下,长石回收率为70.99%,石英回收率为1.09%,差值达69.9%,分离效果显著。Zeta电位和红外光谱分析表明,油酸钠对长石不仅有物理吸附还存在化学吸附作用,对石英仅有物理吸附,因而对长石有更强的捕收能力。     

黄锑矿晶体及表面基因特性与可浮性关系研究

采用第一性原理计算了黄锑矿体相、（001）表面以及水分子在其表面吸附的结构性质,利用 XPS 和表面电位分析了黄锑矿单矿物表面特性,讨论了黄锑矿晶体结构、表面性质与可浮性之间的关系,并利用单矿物浮选试验进行了验证。结果表明,黄锑矿中氧原子的活性较强,锑原子的活性较弱,水分子容易在黄锑矿的表面吸附,导致常规阴离子捕收剂难以吸附于黄锑矿的表面,而需要通过金属阳离子活化。黄锑矿在 pH>2.4 的范围内带负电,阳离子捕收剂通过静电作用,容易在黄锑矿的表面吸附。单矿物浮选试验中,铜离子活化后的黄锑矿可以很好地被油酸钠捕收,十二胺离子也可以很好地浮选表面荷负电的黄锑矿。矿物表面基因特性与矿物可浮性有很好的对应关系。     

油酸钠与十二胺作用下黑云母的浮选行为及作用机理研究

通过纯矿物浮选试验,研究了黑云母在油酸钠和十二胺为捕收剂时的浮选行为。结果表明,油酸钠单独作用时,对黑云母基本没有捕收作用;十二胺在强酸性条件下对黑云母有较强捕收作用;二者混合使用对黑云母的捕收作用最强,在中碱性条件下的浮选回收率可达80%以上。Zeta电位、红外光谱测试及溶液化学计算结果表明,十二胺在黑云母表面发生了物理吸附作用;单一油酸钠在黑云母矿物表面不发生吸附作用;十二胺主要以RNH_3~+离子和离子-分子缔合物RNH_3~+·RNH_2的形式吸附于黑云母表面;油酸的水解组分都不与黑云母矿物作用;油酸钠与十二胺水解组分的电性中和,降低了捕收剂的临界胶束浓度,二者的共吸附效应可以改善黑云母表面的疏水性,从而使浮选效果变好。     

阴阳离子混合捕收剂用于中低品位锂云母的浮选实验研究

以阳离子的十二胺DDA和阴离子的油酸钠NaOL为混合捕收剂体系,对中低品位锂云母矿物的浮选进行试验研究和相关测试。通过AFM分析对比云母表面捕收剂吸附形貌结构变化,推测混合捕收剂的协同作用机理可能是十二胺首先在锂云母表面进行有效吸附,油酸钠"间接"地通过头基间的静电吸引或是碳链之间的疏水作用,从而增加表面碳链密度和高度并使得吸附层更加稳定。浮选结果表明,矿物的粒径在50～74μm时浮选效果最好,过粗则锂云母与脉石不能有效分离,而过细则会造成脉石夹带严重;而药剂比例浓度也影响浮选效果,DDA与NaOL用量在2∶1时吸附效果最好。浮选产品的泡沫高度、稳定性试验以及含水量的测试也显示,NaOL有效地减少了浮选泡沫的含水量而降低对脉石的夹带,且使泡沫稳定性有所变弱,半衰期更短,消泡更加容易。另外对比不同的捕收剂添加顺序发现,先加入DDA后加入NaOL的情况下浮选效果最好,也从侧面印证NaOL可能是通过DDA的桥接而起到强化吸附的作用。     

调整剂和油酸钠添加顺序对硅酸盐矿物浮选的影响

以高纯度、无污染的硅酸盐矿物和石英为浮选对象,油酸钠、金属阳离子分别为捕收剂和调整剂,在交换金属阳离子和油酸钠添加顺序的情况下,研究了石榴子石、绿柱石、锂辉石、角闪石、云母、长石和石英的浮选回收率随金属阳离子Fe³⁺、Al³⁺、Pb²⁺和Cu²⁺投加量变化的规律。     

阴阳离子混合捕收剂用于中低品位锂云母的浮选试验研究

以阳离子的十二胺DDA和阴离子的油酸钠NaOL为混合捕收剂体系,对中低品位锂云母矿物的浮选进行试验研究和相关测试。通过AFM分析对比云母表面捕收剂吸附形貌结构变化,推测混合捕收剂的协同作用机理可能是十二胺首先在锂云母表面进行有效吸附,油酸钠"间接"地通过头基间的静电吸引或是碳链之间的疏水作用,从而增加表面碳链密度和高度并使得吸附层更加稳定。浮选结果表明,矿物的粒径在50～74μm时浮选效果最好,过粗则锂云母与脉石不能有效分离,而过细则会造成脉石夹带严重;而药剂比例浓度也影响浮选效果,DDA与NaOL用量在2∶1时吸附效果最好。浮选产品的泡沫高度、稳定性试验以及含水量的测试也显示,NaOL有效地减少了浮选泡沫的含水量而降低对脉石的夹带,且使泡沫稳定性有所变弱,半衰期更短,消泡更加容易。另外对比不同的捕收剂添加顺序发现,先加入DDA后加入NaOL的情况下浮选效果最好,也从侧面印证NaOL可能是通过DDA的桥接而起到强化吸附的作用。     

在高分子絮凝中的捕收剂效应

本文研究了阴离子捕收剂十二烷基硫酸钠、阳离子捕收剂十二胺和两性捕收剂十二烷胺双甲基膦酸对细粒赤铁矿和石英絮凝行为的影响,研究了锡石捕收剂苯乙烯膦酸、油酸钠和苄基胂酸在细粒锡石絮凝中的作用,所用的高分子絮凝剂是磺化聚丙烯酰胺。结果表明,捕收剂能强化细粒矿物的高分子絮凝,提高细粒矿物的选择性絮凝效果。机理研究揭示了在高分子絮凝中的捕收剂效应包括三种作用:静电效应、助凝效应和盐析效应,其中捕收剂对高分子絮凝剂产生的盐析效应是捕收剂强化高分子絮凝选择性的主要机理。     

新型捕收剂浮选锂辉石的作用机理研究

通过浮选试验、表面张力测试、Zeta电位以及红外光谱分析,考察了油酸钠(NaOL)、脂肪酸甲酯磺酸钠(MES)两种捕收剂及其组合对锂辉石的浮选性能及作用机理。结果表明:单一捕收剂在一定浓度下都能较好的浮选锂辉石,其中MES的捕收性能强于NaOL,组合捕收剂浮选效果明显优于单一捕收剂。捕收剂用量为200 mg/L,NaOL∶MES=5∶1摩尔比组合的浮选效果相对最佳。红外光谱研究表明NaOL在锂辉石表面是以化学吸附为主,MES则是以物理吸附为主,两种捕收剂组合后并没有生成新物质,而是由于锂辉石矿物表面为非均质体,同时不同活性质点间的差异使其具有选择性地吸附在不同位置的矿物表面。     

The effect of grinding conditions on the flotation of a sulphide copper ore

The challenge of process development for the beneficiation of Salobo’s copper ore started in 1978 and the studies still go on. Copper is predominantly present as secondary minerals, such as chalcocite, bornite, and digenite, and liberation requires very fine grinding. These minerals may undergo rapid oxidation at the alkaline pH range and under mildly oxidising conditions. The oxidation products may adsorb onto the minerals altering their surface characteristics, flotation behaviour, and may also significantly modify the mechanisms of interaction between the minerals and the collector. These facts impair the flotation process performance and increase the reagents consumption, the required flotation cells volume, and the overall processing costs. This paper describes the effect of grinding conditions on the flotation performance. Different media and mill construction materials were tested at bench scale aiming at evaluating the effects of the pulp electrochemical potential and the availability of iron oxide and hydroxide compounds on the flotation response. The results indicated that the grinding process affects significantly the flotation metallurgical performance of Salobo’s ore. The conditions that yielded the highest levels of copper recovery and the fastest flotation kinetics were rubber lined steel mill and stainless steel media.     

Pyrite and pyrrhotite open circuit potentials study: Effects on flotation

In this research, effects of chloride & sulfate ions and pH changes on the open circuit potentials of pyrite, pyrrhotite and steel and also their reduction-oxidation processes were studied. These potentials were measured at different pH values in 3 electrolytes: distilled water, sodium chloride solution and sodium sulfate solution. A pair of electrodes including reference and operative electrodes was used for measurement and control of potentials. The results showed that with pH increasing, pyrite and pyrrhotite open circuit potentials decrease whereas under the same conditions the mentioned potential for steel rises. It was also observed that use of sodium chloride and sodium sulfate solutions as electrolyte decreases the open circuit potentials, because the presence of chloride and sulfate ions speeds up the oxidation-reduction process. Furthermore, the effect of the mentioned parameters on galvanic interactions between minerals and grinding media in grinding circuits, as well as galvanic interactions between the minerals in flotation process, mineral floatability and their collector adsorption have been discussed.     

磨矿介质对两种碳酸盐浮选的影响

采用钢球和氧化锆球两种球介质,研究了磨矿介质对菱锌矿和菱镁矿表面性质及油酸钠浮选体系中浮选回收率的影响。研究结果表明,在油酸钠浮选体系中,采用氧化锆球介质磨矿,其磨矿产品的浮选回收率大于钢球介质磨矿的浮选回收率。pH试验结果表明,pH=9时,此时两种矿物浮选回收率最高,氧化锆球介质湿磨菱锌矿和菱镁矿的浮选回收率分别为90.19%和89.66%,而两种矿物钢球介质湿磨的浮选回收率分别为73.89%和69.64%。随着浮选槽中油酸钠浓度的增加,两种矿物浮选回收率逐渐增加,油酸钠用量为9×10-5mol/L时,菱锌矿和菱镁矿氧化锆球介质湿磨浮选回收率分别为98.15%和96.94%,而钢球介质湿磨的浮选回收率分别为97.82%和84.66%。     

Influence of galvanic interaction between chalcopyrite and some metallic materials on flotation

Galvanic interactions between the grinding media and the ground mineral inside a ball mill could not only accelerate the media wear but also adversely affect the flotation response of the ground mineral. Rest potential, combination potential and galvanic current measurements were carried out to understand the probable electrochemical interactions between chalcopyrite and several metallic electrodes such as platinum, stainless steel, hyper steel, mild steel and cast iron. Flotation recovery of chalcopyrite was found to be significantly lowered when contacted with hyper steel, mild steel or cast iron prior to flotation unlike with platinum or stainless steel. The influence of the presence of collector during galvanic interaction as well as the effect of relaxation for fresh and galvanically interacted chalcopyrite samples were also studied with respect to its floatability. AES and ESCA analyses indicated that galvanic coupling of chalcopyrite with a hyper steel grinding medium resulted in the formation of hydroxide or oxide species of iron on the mineral surface. An electrochemical mechanism is proposed to explain the mineral-grinding media interaction and its effect on flotation.     

特戊羟肟酸的合成及其对铝硅矿物的浮选性能研究

采用羟胺法合成了特戊羟肟酸, 并研究了其对铝硅矿物的浮选行为及作用机理。单一捕收剂浮选一水硬铝石时, 特戊羟肟酸的浮选效果优于苯甲羟肟酸; 将特戊羟肟酸和油酸钠按1∶1进行复配, 浮选研究结果表明, 复配捕收剂既能提高一水硬铝石的回收率, 又能降低伊利石和高岭石的回收率, 具有更好的选择性; pH=7, 复配捕收剂浓度60 mg/L时, 一水硬铝石回收率可达86.8%。通过接触角、Zeta电位和红外光谱分析等对捕收剂与矿物表面的作用机理进行了探究, 发现油酸钠在一水硬铝石表面主要进行物理吸附, 而特戊羟肟酸主要为化学吸附, 二者复配能更有效地与一水硬铝石作用。     

Improving froth characteristics and flotation recovery of phosphate ores with nonionic surfactants

The beneficial effect of a series of nonylphenol polyethylene glycol ether surfactants were tested in the flotation of phosphate ores in which the mixtures of sodium oleate and dodecane were used as collectors. In order to elucidate the flotation results, equilibrium surface tension of single and binary surfactant solutions prepared with sodium oleate and nonionic surfactants were investigated. Synergism between surfactants was determined by observing the change in surface tension of solutions and by the calculation of interaction parameter from surface tension data. The lowering of surface tension of sodium oleate solutions was observed in the presence of nonionic surfactants. The interaction parameter between sodium oleate and a nonionic surfactant (i.e., NP-4) was calculated to be −0.21, showing attraction between the two surfactant molecules. The nonionic surfactant NP-4 was then tested in batch flotation of phosphate ores. The beneficial effect of nonionic surfactant was obtained at different collector dosages and surfactant combinations.     

The interaction of lignosulfonate dispersants and grinding media in copper–gold flotation from a high clay ore

This study was conducted to explain an inconsistent observation in the previous study that a lignosulfonate-based polymeric dispersant improved copper and gold flotation from high clay ores significantly in laboratory but clear improvement was not observed during the full-scale plant trial (Seaman et al., 2012). In this study the flotation of low and high clay ores after grinding with different grinding media was performed to understand the interaction of lignosulfonate dispersant and grinding conditions equipped with rheology measurements and EDTA (ethylene diamine-tetra acid) extraction. It was found that lignosulfonate dispersant mitigated the negative effect of clay minerals on copper and gold flotation when the amount of iron oxidation products originated from the grinding media was minimised. Mild steel media produced a great amount of iron oxidation products depressing copper and gold flotation and masking the role of the dispersant.     

褐铁矿浮选的有效捕收剂及其机理研究

研究了油酸钠、731、苯甲羟肟酸、C_7~9羟肟酸等几种代表性捕收剂对褐铁矿、萤石、高岭土、石英等纯矿物的浮选。结果表明: 油酸钠是褐铁矿的良好捕收剂, 当油酸钠用量为3×10^-4 mol/L, pH值为6.5～10.5时, 褐铁矿可浮性最好。机理研究表明: 在试验pH值范围内, 油酸钠在褐铁矿表面产生了显著的吸附, 表面零电点由pH=8.0左右漂移至pH=3.0左右。在pH=2.0～4.0的范围内, 油酸根在褐铁矿表面发生静电吸附, 油酸分子在褐铁矿表面以氢键作用为主; 当pH=4.0～10.5时, 油酸根与褐铁矿表面铁质点间以化学作用为主, 红外光谱分析显示其作用产物为油酸铁。     

六偏磷酸钠对菱镁矿与白云石浮选分离动力学的影响

以油酸钠为捕收剂,研究了六偏磷酸钠对菱镁矿和白云石浮选行为和浮选动力学特性的影响。结果表明：不添加六偏磷酸钠时两种矿物可浮性相近,分离困难;在矿浆pH值为9-11.5的区间里,添加适量的六偏磷酸钠,菱镁矿仍保持较好的可浮性和较高的浮游速度,而白云石的可浮性和浮游速度大幅降低,从而有利于两种矿物浮选分离。菱镁矿和白云石的浮选分别符合经典一级动力学模型和二级矩形分布模型。     

磨矿介质对两种铜镍硫化矿石浮选行为的影响研究

磨矿作业对矿物浮游性及浮选分离有重要的影响。本研究以分别产自中国和南非的两种不同铜镍矿为研究对象,研究了磨矿介质种类对铜镍矿石浮选行为的影响。研究结果表明,磨矿介质种类对两种矿石中铜镍矿物浮选回收率、浮游速度和脉石矿物的浮选行为的影响规律并不相同,且与报道中纯矿物体系中磨矿介质的影响规律不完全一致。与铸铁介质磨矿相比,采用不锈钢球介质磨矿后,中国铜镍矿混合浮选硫化铜浮游速度更快,可以获得较高的铜、镍品位,混合精矿中脉石含量显著降低。南非铜镍矿经铁介质磨矿后的铜、镍回收率高于惰性介质磨矿。两种矿石的矿物组成差异可能是磨矿介质对其浮选行为影响规律存在差异的主要原因。