捕收剂CSU-A与黄铜矿作用机理

通过矿物浮选实验、吸附量测试以及红外光谱分析，研究CSU—A与黄铜矿和黄铁矿相互作用的规律．浮选实验结果表明，当CSU—A的质量浓度为6mg／L，溶液pH值为9．0～9．5时，CSU—A对黄铜矿捕收能力强，对黄铁矿捕收能力弱；红外光谱分析结果表明，捕收剂CSU—A与黄铜矿和黄铁矿作用前、后的红外光谱图明显不同，在黄铜矿与药剂作用后出现了6cm^-1的波数位移，而黄铁矿与捕收剂作用前、后的红外光谱图基本上没有变化．由此可以确定，捕收剂CSU—A在黄铜矿表面发生了化学吸附，而在黄铁矿表面仅是简单的物理吸附．捕收剂CSU—A具有选择性的主要原因是在黄铜矿和黄铁矿表面发生吸附的形式不同．     

辛基羟肟酸浮选锡石的机理

为探明辛基羟肟酸对锡石的捕收性能及其吸附机理,本文通过单矿物浮选实验,考察了辛基羟肟酸、水杨羟肟酸和苯甲羟肟酸体系中锡石的浮选行为,通过吸附量测定、红外光谱测试、动电位、光电子能谱分析、溶液化学计算研究了辛基羟肟酸对锡石的作用机理.浮选实验结果表明:辛基羟肟酸对锡石的捕收能力明显强于水杨羟肟酸和苯甲羟肟酸,当辛基羟肟酸质量浓度为50mg/L,pH为10左右时,锡石的回收率最高达到91.79%.吸附量测试结果显示:在pH为10时,辛基羟肟酸在锡石表面的吸附量最大为0.23mg/g,与浮选结果一致.XPS分析,Zeta电位和红外光谱测试结果表明:辛基羟肟酸在锡石表面主要发生化学吸附,同时也可能存在物理吸附.辛基羟肟酸的溶液化学计算得出:对锡石浮选起主导作用的是离子-分子缔合物.辛基羟肟酸在锡石表面形成强疏水性的缔合物,可作为锡石的强效捕收剂.     

表面氧化磁黄铁矿的高效捕收研究

针对硫化铜镍矿石中有用矿物易被氧化造成浮选回收率降低的问题,选用磁黄铁矿作为研究对象,通过单矿物浮选试验、吸附量测试和X射线光电子能谱检测,揭示了羟肟酸类捕收剂和黄药类捕收剂与氧化的磁黄铁矿的作用机理.结果表明:选择能直接与矿物表面的氧化产物作用的捕收剂是浮选表面氧化硫化矿的一种可行思路.弱碱性条件下苯甲羟肟酸是表面氧化磁黄铁矿的高效捕收剂,苯甲羟肟酸与氧化的磁黄铁矿表面的氧化膜主要发生"O,O"螯合,苯甲羟肟酸作用后矿物表面亲水性的Fe(OH)_3相对含量减少了37.18%.弱碱性环境下,丁基钠黄药对表面氧化的磁黄铁矿捕收能力弱,主要是因为丁基钠黄药虽然能够较好吸附在氧化的磁黄铁矿表面,但氧化的磁黄铁矿表面的亲水性物质不会减少.     

还原焙烧铁矿磁选精矿的工艺矿物学及反浮选机理研究

运用矿物解离度测定仪,研究了酒钢还原焙烧磁选精矿的化学组成、矿物成分、解离度、共生关系.单矿物浮选试验表明,当pH=6~10,新型阳离子捕收剂GE-609用量为5×10-5 mol/L时,石英的回收率大于80%,而磁铁矿的回收率小于20%.采用GE-609对焙烧磁选精矿进行反浮选试验,采用一粗一精四扫的闭路流程,获得了产率82.42%,TFe品位62.17%,回收率92.59%的精矿.Zeta电位、溶液化学、吸附量和红外光谱研究表明:pH=6~10时,石英(PZC=2.3)表面主要为负电荷,对[RNH4]2+,[RNH3]+电性吸附作用强,吸附量较大,可浮性较好;而磁铁矿(PZC=6.4)表面荷负电少,对阳离子药剂的吸引力弱,吸附量小,可浮性差.     

深度氧化脂肪酸MG-2浮选胶磷矿的性能及机理

对碳酸盐脉石胶磷矿浮选捕收剂深度氧化脂肪酸MG-2的浮选性能与作用机理和NaOL进行了对比。纯矿物试验表明,MG-2的耐低温性更好,捕收力更强。实际矿物浮选中,MG-2表现出良好的选择性。单一正浮选闭路试验指标为:精矿的P2O5含量29.36%,尾矿P2O5含量为4.70%,P2O5总回收率达到了88.49%,取得了较好指标。通过吸附量测试、CMC值测试和红外光谱测试,研究了温度和药剂浓度对MG-2在矿物表面吸附的影响。结果表明,MG-2在胶磷矿表面主要为牢固的化学吸附。     

N-十二烷基乙二胺在石英表面的吸附机理

采用单矿物浮选试验探讨了N-十二烷基乙二胺(ND)对石英的捕收性能,通过动电位测试、X-射线光电子能谱分析和表面自由能计算分析其在石英表面的吸附机理.结果表明,与十二胺相比,ND对石英具有更好的捕收能力,在捕收剂用量为41.7mg/L,pH=6.6时,石英回收率达到最大值98.10%.表面自由能计算结果表明,石英表面吸附ND后的表面自由能明显降低,疏水性增强;X射线光电子能谱分析和动电位测试结果表明,ND与石英表面主要发生了静电和氢键吸附.     

黄铁矿浮选中抑制剂WHL-Y1降镁的作用机理

在黄铁矿浮选中,使用抑制剂WHL-Y1可有效地降低精矿中MgO含量.通过工艺矿相研究及吸附量、Zata电位、红外光谱测定,研究了WHL-Y1的作用机理:WHL-Y1中的-P-OH离子可以与矿物表面的Mg2+(Ca2+)发生化学反应,增强不纯黄铁矿的亲水性,在浮选时使其受到抑制,较纯黄铁矿可以优先浮选分离.     

阴离子淀粉对一水硬铝石和伊利石浮选行为的影响

通过浮选实验、动电位和吸附量测定,考察了阴离子淀粉在一水硬铝石和伊利石浮选分离中的效果与作用机理.单矿物浮选实验表明,在阳离子捕收剂(DTAC)体系中,阴离子型淀粉(LSDZ)在pH=4～11的范围内抑制了一水硬铝石的浮选.当pH=6,c(DTAC):3×10-4 mol/L时,随着阴离子淀粉LSDZ用量的提高,一水硬铝石被抑制;当c(LSDZ)＜40 mg/L时,活化伊利石的浮选,继续提高淀粉用量,则伊利石被抑制.结果表明:阴离子淀粉是反浮选分离一水硬铝石和伊利石的有效调整剂,LSDZ通过氢键与静电力作用吸附在铝硅矿物表面,阳离子捕收剂使矿物表面ζ-电位正移,阴离子淀粉使矿物表面ζ-电位负移,且阴离子淀粉的加入能促进捕收荆DTAC在矿物表面的吸附.     

黄铁矿浮选中抑制剂WHL-Y1降镁的作用机理

在黄铁矿浮选中,使用抑制剂WHL-Y1可有效地降低精矿中MgO含量.通过工艺矿相研究及吸附量、Zata电位、红外光谱测定,研究了WHL-Y1的作用机理：WHL-Y1中的-P-OH离子可以与矿物表面的Mg^2＋（Ca^2＋）发生化学反应,增强不纯黄铁矿的亲水性,在浮选时使其受到抑制,较纯黄铁矿可以优先浮选分离.     

N,N-二乙基-N-十六烷基胺的合成及其对铝硅矿物浮选性能的影响

以十六胺、甲酸和乙醛为原料,合成了阳离子捕收剂N,N-二乙基-N-十六烷基胺(DEN16),通过单矿物和人工混合矿浮选实验以及红外光谱和Zeta电位测试,考察了其对一水硬铝石、高岭石和伊利石的浮选行为以及矿物与药剂的作用机理.浮选结果表明:在pH=5～5.5,DEN16用量为2×10-4mol/L时,高岭石、伊利石的回收率均高于82%,而一水硬铝石仅为60%;人工混合矿浮选精矿的铝硅比均高于20,说明在pH8时,以DEN16为捕收剂可以实现铝硅酸盐与一水硬铝石的分离.红外光谱和Zeta电位研究结果表明,DEN16与3种矿物的作用皆为静电吸附,且与高岭石和伊利石的作用强于一水硬铝石.     

Influences of collector DLZ on chalcopyrite and pyrite flotation

The interaction mechanism of collector DLZ in the flotation process of chalcopyrite and pyrite was investigated through flotation experiments, zeta potential measurements and infrared spectrum analysis. Flotation test results indicate that DLZ is the selective collector of chalcopyrite. Especially, the recovery of chalcopyrite is higher than 90% in neutral and weak alkaline systems, while the recovery of pyrite is less than 10%. When using CaO as pH regulator, at pH=7-11, the floatability of pyrite is depressed and the recovery is less than 5%. Zeta potential analysis shows that the zeta potential of chalcopyrite decreases more obviously than that of pyrite after interaction with DLZ, confirming that collector DLZ shows selectivity to chalcopyrite and pyrite. And FT1R results reveal that the flotation selectivity of collector DLZ is due to chemical absorption onto chalcopyrite surface and only physical absorption onto pyrite surface.     

Effect of organic depressant lignosulfonate calcium on separation of chalcopyrite from pyrite

In order to selectively separate chalcopyrite from pyrite, the effect of organic depressant lignosulfonate calcium (LSC) on the flotation separation of chalcopyrite from pyrite was investigated by flotation tests. The depression mechanism was studied by Fourier-transform-infrared (FTIR) analysis. The flotation tests of single mineral show that LSC can depress the flotation of pyrite in a certain pH range, but it has little effect on chalcopyrite flotation. Flotation separation of a mixture of chalcopyrite and pyrite can be completed to obtain a copper concentrate grade up to 24.73% with a recovery of 80.36%. IR analysis shows that LSC and butyl xanthate compete in absorption on pyrite surface, and there exists an LSC characteristic peak on pyrite surface. There is little adsorption of LSC on chalcopyrite.     

Effect of sodium pyrophosphate on the flotation separation of chalcopyrite from galena

The effect of sodium pyrophosphate (SPH) on the separation of chalcopyrite from galena was examined through flotation, adsorption, electrokinetic studies and infrared spectral analysis. Differential flotation tests indicate that satisfactory separation can be achieved within the pH range from 2.5 to 6 using SPH to depress the galena, but not the chalcopyrite when O-isopropyl-N-ethyl thionocarbamate (IPETC) is used as the collector. The electrophoretic mobilities of both the minerals dramatically become negatively charged following SPH adsorption in the pH range from 2.5 to 12. The infrared spectral analysis suggests that chemical adsorption occurs on galena surface treated by SPH, indicating that a chelate complex has formed. At weakly acidic pH values, the adsorption density of IPETC onto galena is significantly reduced in the presence of SPH. However, the amount of IPETC adsorbed onto chalcopyrite almost remains at the same level. Since the observed adsorption density of IEPTC onto chalcopyrite is quite high compared to galena, the observed flotation results are explained. A possible mechanism for the interaction between the two sulphide minerals and SPH is discussed.     

Surface chemical study of the selective separation of chalcopyrite and marmatite

FCLS (Ferric Chromium Lignin Sulfonate) was used to aid the separation of chalcopyrite from marmatite. Flotation, adsorption and zeta-potential tests of treated marmatite and chalcopyrite were performed. The flotation of marmatite was strongly depressed, while that of chalcopyrite was only slightly depressed, over a wide range of pH values when FCLS was used as depressant in the presence of Butyl Xanthate (BX). The adsorption of BX onto chalcopyrite or marmatite takes place over a wide pH range. The adsorption density of BX on chalcopyrite and marmatite decreases as the pH increases. The adsorption density of FCLS onto marmatite is greater than the adsorption density onto chalcopyrite. The zeta potentials of chalcopyrite and marmatite become more negative due to the addition of xanthate and FCLS.     

Process mineralogy of copper-nickel sulphide flotation by cyclonic-static micro-bubble flotation column

In our study we investigated a refractory copper-nickel sulfide ore separation by using a cyclonic-static micro-bubble flotation column (FCSMC). The process mineralogy of the main products was studied. Using a scanning electron micro-scope-energy dispersive system (SEM-EDS) and an X-ray spectrometer the mineral category and content of samples were analyzed. By using a mineral liberation analyzer (MLA) the mineral liberation characteristics were revealed. It is shown that in roughing feed the monomers liberation degree of nickel pyrite and chalcopyrite take up 84.11% and 88.82%, respectively. In tailings, the lost nickel pyrite and chalcopyrite are mainly monomers. Therefore, strengthening the micro-fine particle recovery capacity is the key to increase recovery.     

Flotation behavior and adsorption mechanism of fine wolframite with octyl hydroxamic acid

Flotation behavior and adsorption mechanism of octyl hydroxamic acid(OHA)on wolframite were investigated through flotation experiments,adsorption tests,zeta-potential measurements,infrared spectroscopy and solution chemistry calculations.Results of flotation and adsorption experiments show that the maximum values of flotation recovery and adsorption capacity occur around p H 9.In term of the solution chemistry calculations,the concentration of metal hydroxamate is greater than that of metal tungstate and metal hydroxyl,and metal hydroxamate compounds are identified to be the main species on wolframite surface at p H region of 8-10,contributing to the increase of OHA adsorption and flotation performance.Results of zeta-potential and IR spectra demonstrate that OHA adsorbs onto wolframite surface by chemisorptions.Hydroxamate ions can bond with Mn_2+/Fe_2+cations of wolframite surface,forming metal hydroxamate compounds,which is a key factor in inducing the hydrophobicity of wolframite under the conditions of maximum flotation.     

Selective separation of silica from a siliceous-calcareous phosphate rock

Selective separation of silica from a siliceous-calcareous phosphate ore that had been sieved into different size fractions is investigated by a combination of chemical analysis, zeta potential measurement and FTIR and XPS techniques. Scrubbing is a better choice than flotation for removing silica from the coarse fractions. The P2O5 grade of the coarse fractions is increased to about 30% by scrubbing and the product yields are higher than those obtained by flotation. The silica in the fine fraction is separated by reverse flotation. An alkyl amine salt (DAH) is an effective collector and the P2Os grade of the fine fraction can be increased by 7% to beyond 30% under acidic conditions. The higher zeta potential obtained using DAH suggests that it is more strongly absorbed onto the ore panicles than the other cationic collectors.FTIR and XPS results confirm physical absorption of the cationic collector onto the ore surface. They also indicate that calcite is dissolved at low pH values, which increases the Si concentration on the ore surface.     

Mechanism of separating pyrite and dolomite by flotation

To study the mechanism of separating pyrite and dolomite by flotation, the acting mechanisms of WHL depressor and both the minerals were studied by means of thermogravimetric and differential thermal analysis （TG-DTA）, Fourier transform infrareddiffuse reflection spectroscopy （PTIR-DRS）, and X-ray photoelectron spectroscopy （XPS）. The results indicated that WHL formed metal salts with metal ions dissolved in water from dolomite and pyrite, which then deposited on their surfaces. Both of the minerals could be depressed by WHL. In the process of flotation, sulfur was created besides the WIlL being absorbed on the surface of the sulfur concentrate, and its recovery rate was slightly affected.     

Flotation behavior of four dodecyl tertiary amines as collectors of diaspore and kaolinite

The flotation of diaspore and kaolinite by one of a series of tertiary amines (DRN, DEN, DPN and DBN) was investigated. The tertiary amines show better floating recovery for kaolinite compared to diaspore. The maximum recovery D-value is 45% over a pH range from 3 to 8. FT-IR spectra confirm the presence of hydroxyl groups on the surface of kaolinite and diaspore. Zeta potential measurements show that the mineral surfaces are negatively charged over a wide pH range. Ionization of hydroxyl groups mainly accounts for the surface charging mechanism. The adsorption of tertiary amines onto the mineral surface is due mainly to electrostatic effects and the difference in electrostatic effect between a collector and the two minerals can explain the flotation separation. Inductive electronic and steric effects from the substituent groups result in different collecting powers for the four tertiary amines.     

Effect of pyrite content of feed and configuration of locked particles on rougher flotation of copper in low and high pyritic ore types

Misreported pyrite into copper concentrates dramatically declines copper grade and recovery. Copper flotation can be also more complicated if flotation feed comes from an elevated-pyritic copper ore. In this investigation, the effect of two different ore types(high pyritic and low pyritic feeds) was studied on rougher stage of industrial copper flotation circuit. Samples were taken from different streams and the structure of chalcopyrite within the pyrite and non-sulfide gangue minerals was examined in various size fractions for mentioned ore types. Results indicated that 72% and 56% of the total floated pyrite was transferred to concentrate in first four cells in the low and high pyritic feeds, respectively. Whereas, this proportion for floated SiO_2 in last ten cells was detected as 72% and 71%, respectively. A detailed interpretation of the effect of locked particles in different size fractions on rougher flotation cells is studied from industrial point of view.