氧肟酸高分子药剂在铝土矿反浮选中的作用

通过浮选试验，研究了氧肟酸淀粉和氧肟酸聚丙烯酰胺两种高分子药剂对铝土矿中一水硬铝石和高岭石浮选行为的影响。结果表明：氧肟酸淀粉在酸性条件下对一水硬铝石有较强的抑制作用，而对高岭石有活化现象；氧肟酸聚丙烯酰胺在整个试验pH值范围内对两种矿物均有活化作用。两种大分子药剂属于阴离子型，动电位测定结果表明，它们在带负电的高岭石、一水硬铝石表面吸附，使其动电位负性增加，表明药剂与矿物存在氢键力或化学作用力。由于在一水硬铝石表面，氧肟酸淀粉可以罩盖捕收剂十二胺，增加矿物表面的亲水性，从而对其产生抑制作用。而线型氧肟酸聚丙烯酰胺在矿物表面为卧式吸附，其分子链上的负电区能够增加阳离子捕收剂的吸附量，从而活化了一水硬铝石的浮选。     

新型阳离子有机硅QAS222对铝硅矿物浮选行为的研究

考察了自行合成的新型有机硅阳离子表面活性剂QAS222对一水硬铝石、高岭石、叶蜡石和伊利石等4种铝硅矿物的浮选行为,并以其为铝硅酸盐矿物的捕收剂,进行了不同铝硅比的人工混合矿反浮选分离脱硅试验研究。试验研究结果表明,新型阳离子有机硅季铵盐类化合物是铝土矿反浮选脱硅的有效捕收剂;酸性条件下QAS222对一水硬铝石、高岭石、叶腊石和伊利石表现较好的捕收力,但此时反浮选分离趋势不明显;而在碱性条件下,以QAS222为捕收剂,随着矿浆pH值的上升,4种矿物的可浮性出现了不同程度的减低,尤其是当矿浆pH9后,一水硬铝石的上浮率骤减,铝硅矿物之间表现出了良好的反浮选分离趋势;在矿浆pH值为11时,以QAS222为捕收剂,不添加其它任何抑制剂,成功地实现不同铝硅比的人工混合矿的反浮选脱硅,并获得较好的选别指标——当给矿A/S仅有2.7时,仍能获得精矿A/S为12.82,其中Al2O3品位77.79%、回收率69.91%的较好指标,且当给矿A/S不断增大时,精矿中的A/S,Al2O3的品位和回收率都有所提高。     

捕收剂CTAB对一水硬铝石与高岭石的浮选差异及其分子动力学模拟

为了研究季铵盐类捕收剂对铝土矿反浮选的影响,以十二胺（DDA）为参照捕收剂,考察了十六烷基三甲基溴化铵（CTAB）对一水硬铝石和高岭石浮选回收率的影响,并通过FTIR分析、Zeta电位检测、吸 附量测定以及分子动力学模拟对作用机理进行了系统的分析。浮选试验结果表明,CTAB浮选分离效果优于DDA,在pH=4、CTAB浓度为2×10-4 mol/L时,纯矿物浮选试验一水硬铝石和高岭石浮选回收率相差51.70个百分 点,人工混合矿试验获得了Al2O3品位71.73%、回收率71.26%、SiO2含量9.43%的精矿,铝硅比A/S达到7.60。机理分析结果表明,捕收剂CTAB在一水硬铝石和高岭石表面均有吸附,在高岭石表面的吸附量大于在一水硬 铝石表面的吸附量,且均为物理吸附;分子动力学模拟计算结果表明捕收剂CTAB与高岭石总相互作用能为与一水硬铝石总相互作用能的2.29倍,因此CTAB分子优先吸附于高岭石的表面,具有较高的选择性,有利于反 浮选的进行。     

氟化钠在铝硅酸锌矿石物浮选新工艺试验研究

在季铵盐捕收剂体系中，氟化钠活化了层状硅酸盐矿物高岭石、伊利石和叶蜡石的浮选，而对一水硬铝石的浮选没有影响，可以作为铝土矿反浮选的有效调整剂。氟化钠在矿物表面上发生特性吸附作用，显著降低硅酸盐矿物的Zeta电位，而对一水硬铝石的电位影响不大。AES研究表明，氟离子扩散至硅酸盐矿物颗粒内部，使得其在硅酸盐矿物颗粒上的吸附量很高，而只在一水硬铝石表面发生较低量的吸附。氟离子在硅酸盐矿物颗粒的表面和内部的高吸附量显著降低矿物的动电位，增强捕收剂与矿物的静电作用，从而起到活化作用。     

二元组合捕收剂浮选分离一水硬铝石与高岭石的机理研究

以油酸钠为主要捕收剂,与苯甲羟肟酸组合使用,复配出二元组合捕收剂,再通过单矿物浮选试验考察二元组合捕收剂对一水硬铝石和高岭石两种铝硅矿物的捕收性能。通过表面张力测定和激光粒度测试,系统研究了二元组合捕收剂的浮选作用机理,旨在为我国铝土矿浮选脱硅捕收剂的开发提供理论指导。结果发现,二元组合捕收剂NaOL/BHA对一水硬铝石和高岭石伴生的铝硅酸盐矿物的浮选效果明显超过单一油酸钠捕收剂,研究的二元组合捕收剂中油酸钠与苯甲羟肟酸的最佳摩尔配比为9∶1。二元组合捕收剂溶液的表面张力随着BHA浓度的增加而下降,在较低浓度下表面张力明显下降到拐点达到稳定值,该现象表明组合捕收剂活性高,捕收性能强,拐点处对应的两种药剂摩尔配比与单矿物浮选实验得出的最佳组合摩尔比一致。二元组合捕收剂可以明显促进一水硬铝石颗粒表观粒度增大,使其形成疏水性聚团,致使浮选回收率增大,而对高岭石表观粒度几乎没有影响。     

铝土矿反浮选新型捕收剂TR性能研究

通过对铝土矿反浮选新型捕收剂TR和传统捕收剂1231重要浮选性能的对比研究,揭示了TR在不加任何其他调整剂的情况下,即能在广泛的 pH范围内实现高岭石和一水硬铝石的反浮选分离,且TR的使用量比1231低约50%;TR在用常规调整剂的情况下,精矿铝硅比为10.13,回收率77.14%,明显优于使用1231作捕收剂时的指标,而且精矿泡沫量很小,消泡容易。     

季铵盐捕收剂对铝硅矿物的浮选行为

通过单矿物浮选试验、动电位测定及红外光谱分析研究了十二烷基三甲基氯化铵、十六烷基三甲基溴化铵和十八烷基二甲基苄基氯化铵3种季铵盐捕收剂对铝硅矿物一水硬铝石、高岭石、叶蜡石和伊利石的浮选行为和作用机理.结果表明:在碱性条件下,以季铵盐为捕收剂可实现一水硬铝石与3种硅酸盐矿物的反浮选分离;一水硬铝石、高岭石、叶蜡石及伊利石的等电点分别为pH6.0、3.4、2.3、3.2,随着矿浆pH值提高,这些矿物的表面动电位均呈负增加;季铵盐捕收剂主要靠静电作用吸附在一水硬铝石、高岭石、叶蜡石及伊利石表面.     

Preparation and performance of 4-alkyl-4,4-bis(hydroxycarbamoyl) carboxylic acid for flotation separation of diaspore against aluminosilicates

The existed collector for the flotation of diasporic bauxite in China is poor in selectivity. To look for a collector with high selectivity and strong collecting capacity on the diaspore flotation, novel 4-alkyl-4,4-bis(hydroxycarbamoyl) carboxylic acids (ABHC) including 4,4-bis(hydroxycarbamoyl) dodecanoic acid (HCDA), 4,4-bis(hydroxycarbamoyl) tetradecanoic acid (HCTA), and 4,4-bis(hydroxycarbamoyl) hexadecanoic acid (HCHA) were designed and synthesized for the beneficiation of diasporic bauxite by selective flotation. The results of flotation experiments for the single minerals showed that by using these compounds as collectors, the pulp pH value has significant influence on their collecting performance as the floatability of diaspore varies sharply with its change. The appropriate pH value for the flotation of diaspore gets close to neutral condition at which diaspore presents good floatability while kaolinite and illite exhibit poor floatabilities. HCDA, HCTA, and HCHA, especially HCDA, show good selectivity for the flotation between diaspore and aluminosilicate around pH 7. A satisfactory mass ratio of Al₂O₃ to SiO₂ (A/S) and recovery of Al₂O₃ were obtained from the flotation separation of artificially mixed minerals and the flotation desilication of diasporic bauxite by using HCDA as a collector, proving that the selectivity of HCDA is better than that of the traditional collector oleate. Moreover, adsorption amount, zeta-potential, DFT calculation, XPS, and FTIR were performed to study the mechanisms. The results indicated that the adsorption of HCDA on the surface of diaspore is dominantly chemisorption in the form of three chelate rings. The oxygen atoms contained in carboxyl and hydroxycarbamoyl of the polar group have the highly negative charges and stereo conditions to form five- to eight-membered ring, resulting in the coordination of carboxyl and hydroxycarbamoyl to the metal aluminum atoms to form chelate rings. By contrast, the adsorption of HCDA on the surface of kaolinite or illite is mainly physical adsorption.     

铝土矿浮选新型捕收剂的捕收性能及机理研究

通过一水硬铝石和高岭石的单矿物浮选试验、接触角、红外光谱、和ζ电位测量分析了东北大学研制的DJL-1和DJL-2捕收剂在铝土矿正浮选中的浮选行为和作用机理。一水硬铝石与DJL-1和DJL-2作用后接触角变大、疏水性变强;高岭石与DJL-1作用后接触角几乎不变,与DJL-2作用后接触角变大。DJL-1使一水硬铝石和高岭石表面ζ电位均负向增加,DJL-2对一水硬铝石和高岭石表面ζ电位影响较小,分别使用DJL-1和DJL-2,一水硬铝石和高岭石的最大回收率之差为54.5%和70.5%,DJL-2在更宽的温度和pH范围内获得更好的浮选结果;DJL-1和DJL-2在一水硬铝石表面存在键合吸附和氢键作用,DJL-1与高岭石表面存在氢键作用。结果表明,DJL-1和DJL-2均是铝土矿正浮选的优良捕收剂,且DJL-2更优。     

脉石矿物与一水硬铝石的反浮选分离研究

针对我国铝土矿资源的实际情况,对一水硬铝石与主要脉石矿物的反浮选分离作了初步研究。并以BS-1为组合捕收剂、TZ-1为改性调整剂,在弱酸性介质中对极难处理的高硅铝土矿进行反浮选试验研究,取得了精矿铝硅比10.01,综合回收率为83.13%的试验指标。     

Role of crystal structure in flotation separation of diaspore from kaolinite,pyrophyllite and illite

Wettability and electrokinetics of kaolinite, illite, pyrophyllite and diaspore were measured in the context of reverse flotation using cationic collectors. The results were interpreted by crystal structure analysis of the minerals. The point of zero charge (PZC) was calculated using crystallographic parameters of the minerals and compared well with the corresponding iso-electrical point (IEP) determined experimentally. The decreasing order of the measured IEP or calculated PZC from diaspore to kaolinite, illite and finally pyrophyllite correlated well with decreasing the number of broken Al–O bonds and the ratio of broken Al–O to Si–O bonds. The electrostatic interaction was identified as the main driving force for cationic collector adsorption on the minerals. Satisfactory separation of aluminosilicates from diaspore was achieved by reverse flotation.     

Selective depression of diaspore with waxy maize starch

Highly branched waxy maize starch (WMS) was used to separate diaspore from artificial mixtures of diaspore and kaolinite by microflotation using dodecylamine (DDA) as collector. It was found that WMS depressed the diaspore flotation while activated the kaolinite flotation more or less. The adsorption of WMS on diaspore was examined through adsorption test, zeta potential measurement, infrared spectroscopy, and atomic force microscopy. It is suggested that both chemical interaction and intermolecular hydrogen bonding by hydroxyl groups of starch with surface Al–OH moieties occurred in the adsorption. Results obtained from the adsorption of DDA and WMS on diaspore showed that starch virtually enhanced the DDA adsorption. The depressant action of WMS can be rationalized primarily by the formation of hydrophilic adsorption layer enveloping the surface of diaspore and covering the collector.     

高岭石与一水硬铝石反浮选分离药剂研究

针对我国铝土矿资源的实际情况,对一水硬铝石与主要脉石矿物高岭石的反浮选分离作了初步研究。研究了高岭石和一水硬铝石在十二胺体系中的浮游行为,从二者晶型结构差异入手,解释了高岭石用药量相对较大,以及在酸性条件下仍可大量上浮的原因。使用抑制剂YX-2,二者可浮性出现较大差异。最后配合使用分散剂YF-2,对一水硬铝石:高岭石为2:1的人工混合矿进行反浮选分离。经过一次粗选、一次精选,槽内产品实现回收率(以Al2O3计)75.03％,铝硅比10.66。     

调整剂在浮选分离一水硬铝石和高岭石中的研究

单矿物浮选试验结果表明, 在阳离子捕收剂DTAL 作用下, 调整剂SFL 在pH=2～12 范围内活化高岭石的浮选, 而在弱酸性条件下对一水硬铝石的浮选影响较小。弱酸性条件下的人工混合矿分离试验表明, 随着原矿中一水硬铝石的含量的增加, 精矿铝硅比显著上升, 氧化铝的回收率也随着提高;在调整剂SFL 的作用下, 精矿铝硅比进一步提高。动电位测试研究表明, 与SFL 作用后的一水硬铝石和高岭石的负电位显著增加, 使得阳离子捕收剂通过静电作用力更容易吸附在矿物表面上吸附。吸附量的测试表明:SFL增加了在高岭石表面的捕收剂吸附量, 而在一水硬铝石表面的捕收剂吸附量有所减少。     

A novel surfactant 2-amino-6-decanamidohexanoic acid: Flotation performance and adsorption mechanism to diaspore

In this paper, a novel surfactant, 2-amino-6-decanamidohexanoic acid (AHA-10) was synthesized and used as a collector for flotation separation of diaspore and aluminosilicate minerals. The adsorption mechanism of AHA-10 onto diaspore was also evaluated by FTIR spectra, zeta potential, XPS and solution chemistry. The flotation results demonstrated that AHA-10 exhibited superior collecting power to diaspore and good selectivity against kaolinite and illite, and could effectively recover diaspore from bauxite ores contained aluminosilicate minerals at pH around 10. The analyses of FTIR spectra, zeta potential and solution chemistry inferred that at pH around 10, AHA-10 might chemisorb on diaspore surfaces by formation of AlO and AlN bonds. AHA-10’s unique properties, such as characteristic bond model to Al atoms on diaspore surfaces, double hydrophobic groups and intermolecular hydrogen bonds between neighboring AHA-10 molecules coated on diaspore surfaces, rendering a weakening surface energy and enhancing hydrophobicity of diaspore particles.     

Significance of particle aggregation in the reverse flotation of kaolinite from bauxite ore

Significant interest has been demonstrated for the removal of kaolinite from bauxite ore by flotation. The reverse flotation of kaolinite from bauxite ore at low pH with dodecylamine hydrochloride collector has been reported. However, resolving the mechanism of the reverse flotation process is largely limited by the misunderstanding of the anisotropic surface properties of kaolinite particles. Based on recent fundamental study of the surface properties of kaolinite particles and their interaction, the significance of particle aggregation in the reverse flotation of kaolinite from bauxite ore has been revealed. The wetting characteristics of the basal plane surfaces of kaolinite with dodecylamine hydrochloride collector have been estimated by contact angle measurements at model surfaces. The improved hydrophobicity of the kaolinite nano-particles is not enough to account for the significant increase in the flotation recovery at low pH when compared to the flotation performance at high pH. Instead, particle aggregation is expected to be the major factor which contributes to the improved flotation response at low pH. Both simulation results and X-ray CT results have demonstrated aggregation and formation of kaolinite clusters at low pH. It appears that these kaolinite clusters have sufficient mass and hydrophobicity to account for the successful reverse flotation of kaolinite from bauxite ore at low pH.     

西南地区某高泥堆积型铝土矿选矿试验研究

西南地区某高泥堆积型铝土矿中Al₂O₃、SiO₂含量分别为47.25%、10.86%,铝硅比为4.35;主要目的矿物为硬水铝石,主要脉石矿物为高岭石,其他金属矿物有赤铁矿、针铁矿以及锐钛矿等。矿石中矿物的共生关系较为复杂,目的矿物嵌布粒度不均,单体解离度不高;铁、钛矿物与铝矿物之间紧密共生,难于实现有效分离。针对该矿石采用全泥正浮选的选矿工艺,以氢氧化钠为调整剂、水玻璃为抑制剂,EMB-506为捕收剂,在磨矿细度为-0.074mm占70%的条件下,闭路试验可获得Al₂O₃品位为51.62%,SiO₂品位为6.05%,铝硅比为8.53,Al₂O₃回收率为86.66%的浮选精矿。该工艺流程结构及浮选药剂制度简单,所得浮选精矿达到了拜耳法生产氧化铝对给料的要求。     

某铁矿强磁尾矿反浮选回收试验研究

针对我国西部某铁矿强磁选尾矿进行了反浮选回收铁资源的试验研究, 探讨了pH值、抑制剂可溶性淀粉用量、阳离子捕收剂十二胺用量对浮选指标的影响。结果表明, 在矿浆pH=10、可溶性淀粉用量2 400 g/t、十二胺用量400 g/t条件下进行一粗一精(精选药剂用量减半)闭路反浮选, 可获得铁品位43.88%、回收率50.93%的铁精矿产品。     

贵州某高硫铝土矿反浮选脱硫试验

贵州某高硫铝土矿Al2O3含量为62.60%、硫含量为7.15%,铝硅比为11.54,矿石有用矿物主要为一水硬铝石,属于典型的高品位一水硬铝石型高硫铝土矿。为给该矿石合理开发利用流程确定提供依据,采用反浮选脱硫工艺进行试验。结果表明,在磨矿细度为-0.074 mm占85%条件下,以碳酸钠为矿浆p H调整剂,硫酸铜为活化剂,改性淀粉为抑制剂,丁基黄药为捕收剂,松醇油为起泡剂,经1粗1精2扫、精选尾矿和扫选精矿均返回至粗选闭路流程浮选试验,获得了氧化铝含量72.06%、含硫量0.27%的精矿产品,试验结果可以为该铝土矿的资源开发提供参考。     

云南某低品位铝土矿铝硅浮选分离试验研究

云南文山某低品位铝土矿Al2O3及SiO2含量分别为44.35%、10.52%,Fe及TiO2含量分别为13.36%、4.64%,属于高铁高钛、低铝低硅型铝土矿;可回收铝矿物主要以一水硬铝石相态存在,铁矿物主要包括赤铁矿与针铁矿,钛矿物主要以锐钛矿相态存在,脉石矿物主要为高岭石。对该矿石进行了铝硅浮选分离试验研究,重点考察了捕收剂种类与用量、磨矿细度、调整剂用量、抑制剂种类与用量等条件对浮选效果的影响,确定了以改性组合脂肪酸KYB为捕收剂,硅酸钠+GY 3为组合抑制剂,碳酸钠为调整剂的药剂制度。在磨矿细度为-0.074 mm占90%的条件下,采用“1粗2精1扫”闭路试验可获得铝精矿Al2O3含量为53.34%、铝硅比为9.79、Al2O3回收率为81.62%的技术指标。研究结果可为开发该类铝土矿资源提供技术支撑及借鉴。