BK430在铝土矿反浮选脱硅中的应用

考察了以BK430作为捕收剂对中国铝土矿资源中一水硬铝石、伊利石和高岭石3种典型矿物的浮选行为。单矿物试验结果表明:在不添加抑制剂和弱酸性条件下,BK430对高岭石和伊利石的捕收力明显强于一水硬铝石;添加一水硬铝石抑制剂DF,有助于进一步扩大一水硬铝石与2种铝硅酸盐矿物的可浮性差异;人工混合矿的试验结果与单矿物试验结果比较吻合。对河南某铝硅比为4.43的铝土矿进行了反浮选脱硅试验,经过脱泥—反浮选可以获得Al2O3/SiO2为9.21,Al2O3回收率为62.49%的精矿。BK430有望成为一种在近中性条件下铝土矿反浮选的脱硅捕收剂。     

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.     

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。     

微细粒一水硬铝石与高岭石的浮选分离

本文叙述了应用改性硅酸钠——含铁硅酸作微细粒高岭石的选择性抑制剂,从—10微米微细粒人工混合矿中成功地用油酸钠浮选分离—水硬铝石的新方法及药剂同矿物表面的作用机理。对—10微米的—水硬铝石、高岭石混合矿(铝硅比为3.1),经一次选别得到铝硅比11.4、脱硅率84.6%、一水硬铝石回收率73%的精矿。研究表明,液态高聚合度的含铁硅酸是一种有效的改性抑制剂,加入碱性矿浆后迅速分散、吸附、羟化、水化,使吸附性能较强的高岭石受到强烈的抑制,从而实现它与一水硬铝石有效的浮选分离。     

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。     

一水硬铝石与高岭石反浮选分离研究

详细研究了一水硬铝石和高岭石的浮选行为 ,并以十二胺盐酸盐作为捕收剂 ,在酸性介质 ( pH3 .5 )及中性介质 ( pH7.5 )加调整剂ATNO进行反浮选分离研究 ,得到较好的分离效果 ,精矿A/S >11。同时进行了不同粒级和不同A/S的一水硬铝石和高岭石的反浮选分离 ,结果表明 ,不同的A/S条件下 ,可以得到较好的分离效果 ,但粒级对一水硬铝石和高岭石的分离有较大的影响 ,细粒级一水硬铝石与高岭石分离效果不好 ,有待于进一步研究     

QAX224捕收剂反浮选分离一水硬铝石和高岭石的试验研究

通过浮选试验、动电位和红外光谱测定,考察了以季铵盐QAX224为捕收剂,淀粉为抑制剂,一水硬铝石与高岭石反浮选分离的作用效果和机理。浮选试验表明, 在pH=8～9的范围内,随着抑制剂用量的增加,一水硬铝石几乎全部被抑制,而高岭石则可出现轻微的活化作用。将一水硬铝石和高岭石的人工混合矿反浮选试验后,铝硅比提高到30.79。机理分析表明,捕收剂和抑制剂与高龄石除了物理作用,还出现了化学键合,一水硬铝石与捕收剂主要为静电吸附,与淀粉主要是化学吸附。     

一水硬铝石与高岭石、叶蜡石和伊利石浮选分离中晶体结构的作用

测量了高岭石、伊利石、叶蜡石和一水硬铝石在阳离子捕收剂反浮选时的润湿性和动电行为。通过分析矿物的晶体结构,对测量结果进行了解释。根据矿物的晶格参数计算了矿物的零电点,计算的零电点值与试验测得的等电点值有很好的吻合。等电点测量值和零电点计算值的减小顺序为:一水硬铝石>高岭石>伊利石>叶蜡石,这与Al-O断裂键数目以及Al-O断裂键数目与Si-O断裂键数目的比值减小顺序基本一致。阳离子捕收剂在矿物表面上的吸附作用主要为静电作用。反浮选分离含铝硅酸盐矿物和一水硬铝石获得了满意的结果。     

阳离子聚丙烯酰胺反浮选分离一水硬铝石和高岭石

在分析一水硬铝石和高岭石的晶体结构以及表面性质差异的基础上，通过单矿物实验、人工混合矿实验、ξ—电位和吸附量研究，找到一水硬铝石的有效抑制剂阳离子聚丙烯酰胺。在pH为5．5—8．5的范围内，实验了以十二胺醋酸盐为捕收剂时高岭石和一水硬铝石的反浮选分离。一水硬铝石表面活性Al原子数量多，易与酰胺基团结合，导致阳离子聚丙烯酰胺中的季铵基团定向排列在一水硬铝石表面的外面，阻止大部分十二胺阳离子吸附在其表面，并增大一水硬铝石的亲水性，抑制了一水硬铝石的上浮。而阳离子聚丙烯酰胺对十二胺浮选高岭石影响很小。     

新型螯合剂对一水硬铝石和铝硅酸盐矿物浮选行为的研究

合成了含有羧基和肟基的新型螯合捕收剂HCMT并研究其对一水硬铝石、高岭石和伊利石的浮选行为。单矿物浮选试验表明,该捕收剂对一水硬铝石、铝硅酸盐矿物的捕收能力差别较大,能有效分离一水硬铝石与铝硅酸盐矿物。通过动电位、红外光谱和电镜扫描(SEM)等研究了捕收剂对矿物的吸附机理,结果表明捕收剂在一水硬铝石表面可能是通过COOH、-NHOH与Al-O形成双环螯合物的化学吸附,而在高岭石、伊利石表面主要是物理吸附。     

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.     

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。     

一水硬铝石和含铝硅酸盐矿物在不同调整剂作用下的浮选行为研究

主要考察了以1228作为捕收剂,一水硬铝石和含铝硅酸盐矿物在甲基纤维素、Na2SiF6、SA3、1230和1231等五种调整剂作用下的浮选行为。结果表明,调整剂SA3、1230和1231对一水硬铝石都有抑制作用,但1230和1231对含铝硅酸盐矿物也有不同程度的抑制作用,尤其是对伊利石的抑制作用比较强;甲基纤维素对一水硬铝石和含铝硅酸盐矿物都有很强的抑制作用;调整剂Na2SiF6只有在pH<2.0的条件下才对一水硬铝石显示较强的抑制作用,而且浮选的pH值范围窄。通过对几种调整剂作用进行分析比较,酸性介质中SA3有可能实现一水硬铝石与含铝硅酸盐矿物的选择性分离。     

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.     

Utilization of soluble starch as a depressant for the reverse flotation of diaspore from kaolinite

The utilization of a non-toxic natural polysaccharide, soluble starch, in the flotation of diaspore and kaolinite with emphasis on depression of diaspore in the reverse flotation of bauxite ores by using a Gemini cationic collector, is reported in this work. Firstly, the depressant effect of soluble starch was studied by pure mineral micro-flotation of diaspore and kaolinite as functions of the depressant dosage and pulp pH. The results show that soluble starch depresses diaspore much better than kaolinite. When pH is over 10, a satisfactory separation of the alumina and the silicate minerals can be approached. Moreover, micro-flotation tests of artificial mixed minerals and bench scale reverse flotation of the diasporic bauxite ore was complementing conducted. The non-charged starch is highly proved to be an effective and selective depressant for the reverse flotation of diaspore from the gangue minerals like kaolinite. By zeta potential measurement, adsorption studies and D-IR spectra analysis, the mechanism of interaction between starch and the diaspore surfaces is established, which is the formation of a five membered ring complexes on mineral substrates. The number of broken Al–O bonds of diaspore is much more than that of kaolinite, so the selectivity separation of diaspore from kaolinite in this system is feasible.     

铝土矿浮选的抑制剂研究

主要研究了油酸钠作捕收剂，草酸钠、水杨酸钠等四种小分子有机调整剂对一水硬铝石、叶蜡石、高岭石三种单矿物的作用。结果表明，草酸钠、柠檬酸钠对高岭石和一水硬铝石有抑制作用，水杨酸钠、乳酸钠只对高岭石有抑制作用，四种调整剂对叶蜡石可浮性均无影响。     

Flotation of aluminosilicates using N-(2-aminoethyl)-1-naphthaleneacetamide

The present work deals with the flotation behavior of kaolinite, illite and pyrophyllite with N-(2-aminoethyl)-1-naphthaleneacetamide (AENA). The best recoveries of kaolinite, illite and pyrophyllite were 41.4%, 39.8% and 90.4% respectively. The flotation behavior of three aluminosilicates is almost independent of pulp pH and the collector concentration. The results obtained show that AENA is a stronger collector for pyrophyllite. Conversely it is weaker for kaolinite and illite. By determining the effects of pulp pH on the zeta potential of aluminosilicates, we found that along with the rise in pulp pH, the zeta potential of the aluminosilicate pulp changed gradually from the plus zone to the minus zone. However, there is not a marked change in the floatability of the aluminosilicates. It was shown that the interaction between the collector and the surfaces of the ore particle was not merely electrostatic force, there are also probably hydrogen bonds between them.