褐煤反浮选试验工艺研究

以内蒙古宝日希勒的褐煤为研究对象,通过煤泥反浮选试验和正交试验等,分析研究了褐煤的表面特性和浮选特性,探索提高褐煤浮选效果的药剂种类、用量和工艺.试验结果表明:十二胺(DDA)对褐煤的反浮选效果优于十八胺(ODA)和十六烷基三甲基溴化铵(CTAB);当捕收剂DDA用量为1400 g/t时,反浮选效率最大为6.89％,浮...     

阴阳离子组合捕收剂对微细粒赤铁矿与石英浮选分离的研究

考察了十二烷基磺酸钠（SDS）、十二烷基硫酸钠（SLS）、十二烷基苯磺酸钠（SDBS）以及油酸钠（NaOL）四种阴离子捕收剂分别与阳离子捕收剂十二胺（DDA）组合对浮选分离微细粒(-18μm)赤铁矿和石英的影响。单矿物实验表明,与单一DDA相比,四种阴离子捕收剂分别与DDA组合使用能够降低赤铁矿的浮选回收率,有利于减少赤铁矿的抑制剂用量。十二胺与阴离子捕收剂组合使用时,四种阴离子捕收剂对微细粒赤铁矿和石英分离效果为：SDS>NaOL>SLS/SDBS。其中,DDA+SDS组合捕收剂在一定质量比例条件下组合使用的效果最优,在最佳浮选条件下（pH=7,捕收剂用量为20 mg/L,m(DDA)∶m(SDS)=2∶1,抑制剂用量为20 mg/L）,泡沫产品中石英回收率达到91.05%,赤铁矿回收率仅为6.7%,有利于赤铁矿反浮选。人工混合矿物浮选实验结果表明,使用DDA+SDS组合捕收剂（m(DDA)∶m(SDS)=2∶1）获得精矿Fe品位为45.7%、回收率为87.0%,与单一DDA相比,分别提高了1.7、18.6百分点,有利于提高赤铁矿和石英的分离效果,DDA+SDS可作为微细...     

CTAB与油酸钠混合捕收剂浮选分离磁铁矿与角闪石的研究

采用油酸钠(NaOL)与十六烷基三甲基溴化铵(CTAB)混合捕收剂进行磁铁矿与角闪石的浮选分离研究。分别考察了单一捕收剂CTAB、NaOL和混合捕收剂对单矿物和人工混合矿浮选的影响,借助Zeta电位、FTIR对捕收剂与矿物表面的吸附机理进行了研究。矿物浮选试验结果表明:在pH=5.5,CTAB与油酸钠的摩尔比为2∶1的条件下,混合捕收剂较单一捕收剂具有更好的选择性。Zeta电位和红外光谱结果表明,单一捕收剂CTAB和油酸钠分别以物理吸附与化学吸附的形式吸附在矿物表面,混合捕收剂中油酸钠的存在一定程度上抑制了CTAB在磁铁矿表面的吸附,但不影响CTAB在角闪石矿物表面的吸附。     

阴阳离子组合捕收剂在锂云母浮选气液界面的协同作用机理

以某含Li₂O 1.09%的锂云母矿石为研究对象,将三种阴离子捕收剂油酸钠(NaOl)、十二烷基磺酸钠(SDS)和环烷酸钠(NA)分别与阳离子捕收剂十二胺(DDA)进行复配,借助浮选试验、表面张力、泡沫物化性质测试及协同作用参数计算等手段,从气-液界面研究了阴/阳离子组合捕收剂在锂云母浮选中的协同作用机理。浮选结果表明,三种阴/阳离子组合捕收剂对锂云母的浮选效果均优于单一捕收剂,且当DDA与SDS摩尔比为1∶1时达到最佳浮选效果,精矿中Li2O品位和回收率分别为2.24%和61.88%。而此时浮选泡沫的稳定性达到最低,有利于锂云母的浮选,其浮选泡沫层的高度、半衰期和含水量分别为33 mm,86 s和48.72%。结合表面张力和协同作用参数计算结果可知,在阴/阳离子组合捕收剂体系中,由于正、负电荷相互吸引,致使阴离子捕收剂插入到DDA之间的空隙中,两种捕收剂通过静电力和碳链间的疏水缔合作用相互交织。而由于磺酸基较强的电负性,其降低DDA之间静电斥力的能力更强。相比DDA/NaOl和DDA/NA,DDA/SDS在气-液界面的饱和吸附值增加,捕收剂分子所占的平均最小面积...     

动力煤反浮选的试验研究

以糊精为抑制剂,十二胺(DDA)、十二烷基三甲基氯化铵(DTAC)为捕收剂,通过零调浆方法,研究了不同捕收剂和不同pH值对煤泥反浮选的影响。试验结果表明,DDA对煤泥的反浮选的效果比DTAC好,当糊精的用量为1500g/t、DDA的用量为800g/t时,浮选精矿的灰分为54.38%,浮选尾矿的灰分为19.72%,浮选精矿的灰分和浮选尾矿灰分差值最大可达34.66%,浮选尾矿产率为49.42%,此时取得最佳浮选结果。矿浆的pH值对反浮选有着显著影响,在pH值为4时的酸性矿浆中煤泥反浮选的效果最好。     

用阴阳离子混合捕收剂浮选菱锌矿的研究

本文中研究了戊基钾黄药(KAX)与十二胺(DDA)混合捕收剂中的KAX与DDA重量比对菱锌矿的可浮性和捕收剂在矿物表面上的吸附量的影响.无论单用KAX还是单用DDA时.菱锌矿的浮选回收率均随捕收剂的浓度升高而增大,但此时,仍有40%的菱锌损失了.在用KAX+DDA混合物作为捕收剂时,菱锌矿的浮选回收率大幅度提高.FT-IR光谱测定结果表明,应用混合捕收剂时.胺一黄原酸盐络合物在菱锌矿表面上发生共吸附.混合捕收剂中黄药的存在使得矿物表面与氨离子之间的静电斥力减小,同时使得两种捕收剂的侧向非极性基疏水缔合程度增强.     

阳离子-阴离子组合捕收剂浮选分离白钨矿和方解石

通过纯矿物浮选试验、红外光谱分析、表面张力测定以及动电位测试研究了阳离子捕收剂十二胺(DDA)和阴离子捕收剂油酸钠(NaOL)及其组合捕收剂在白钨矿和方解石浮选分离中的作用及机理。结果表明,当pH值为7左右,DDA和NaOL组合捕收剂总用量为1.5×10^-4 mol/L、组合比为9∶1时,白钨矿回收率达到95%,比单独使用DDA、NaOL以及DDA和NaOL组合比为1∶9时明显提高;在该比例下预先加入2.0×10^-3 mol/L的酸化水玻璃,白钨矿回收率仍然达到90%,而方解石回收率由80%下降到了40%,这可以实现白钨矿和方解石的浮选分离。     

用阳离子和阴离子混合捕收剂浮选菱锌矿的物理化学研究

本文中研究了戊基钾黄药(KAX)与十二胺(DDA)混合捕收剂中的KAX与DDA重量比对菱锌矿的可浮性和捕收剂在矿物表面上的吸附量的影响.无论用单一的KAX还是用单一的DDA时,菱锌矿的浮选回收率均随捕收剂的浓度升高而增大,但此时,仍有40%的菱锌损失了.在用KAX DDA混合物作为捕收剂时,菱锌矿的浮选回收率大幅度提高.FT-IR光谱测定结果表明,应用混合捕收剂时,胺-黄原酸盐络合物在菱锌矿表面上发生共吸附.混合捕收剂中黄药的存在使得矿物表面与氨离子之间的静电斥力减小,同时便得两种捕收剂的侧向非极性基琉水缔合程度增强.     

低阶煤煤泥的淀粉抑制反浮选降灰试验研究

以神东哈拉沟选煤厂加压过滤煤泥为研究对象,以十二烷基胺盐酸盐(DDAH)和十六烷基三甲基溴化铵(CTAB)为捕收剂,淀粉为抑制剂进行了反浮选试验。结果表明:两种捕收剂对煤样中的矿物质都具有捕收作用,捕收剂CTAB选择性较优;淀粉对低阶煤颗粒有显著的抑制作用,浮选尾煤灰分提高了6.92个百分点,可燃体回收率下降了8.72个百分点;在捕收剂与抑制剂协同作用下,捕收剂CTAB表现出较好的选择性。     

十二胺与十二烷基磺酸钠组合捕收剂对赤铁矿浮选的优化及其泡沫性能调控北大核心

采用十二胺进行微细粒级赤铁矿反浮选时具有泡沫产品黏、难消泡的问题。选取赤铁矿和石英两种纯矿物,分别在十二胺(DDA)以及十二胺与十二烷基磺酸钠(SDS)的组合捕收剂体系下,研究了pH值、捕收剂用量及其配比、淀粉用量等对赤铁矿和石英单矿物和混合矿浮选的影响,并进行了泡沫稳定性试验。研究表明,不加入矿物颗粒时,十二胺溶液的气泡平均尺寸小于组合捕收剂(DDA∶SDS=2∶1)的气泡平均尺寸;采用十二胺作捕收剂浮选赤铁矿和石英时,泡沫量更多,气泡小且密集,气泡破裂速度较慢,泡沫更黏更稳定。与单一十二胺捕收剂相比,十二胺和十二烷基磺酸钠组合捕收剂在浮选指标和泡沫性能均体现出了优势。在适宜的药剂制度条件下,十二胺与十二烷基磺酸钠在一定比例条件下组合使用,不仅能够提高浮选指标,还能优化泡沫性能,大幅度降低泡沫黏性。研究对克服阳离子浮选工艺存在的泡沫问题和微细粒级赤铁矿石的浮选具有一定的参考价值。     

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.     

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.     

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。     

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。     

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.     

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。     

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.     

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。     

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。     

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。