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。     

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。     

硫化矿物浮选电化学第三章 硫化矿物浮选电化学理论

<正> 早在三十年代,Gaudin A.M.和Taggart A.F.等人就依据硫化矿物捕收剂金属盐的溶度积数据(见表2-7,图2-7,2-8)提出了硫化矿物浮选的化学理论,如离子吸附,离子交换反应。五十年代初Cook M.A.又提出了中性分子吸附等,从某一侧面解释了硫化矿物与捕收剂的作用机理和硫化矿物浮选规律(如Barsky关系式),但不能说明为什么用黄药浮选硫化矿物时,氧气是一种必需的物质。因而,促使人们从新的角度来研究硫化矿物与硫氢捕收剂的作用机理,提出了硫化矿物浮选的半氧化学说、半导体学说,以及电化学理论。这几种理论的基础都是硫化矿物所具有的半导体性和硫化矿物浮选体系的氧化还原性质,在本质上是一致的。特别是硫化矿物浮选的电化学理论比较全面,深刻地反映了硫化矿物与捕收剂反应过程的实质。通过近三十年的努力,现在已发展成为大家公认的硫化矿物浮选理论。     

钙镁离子对胶磷矿浮选影响机理探讨

金属阳离子因其活性易生成一些新产物,抑制、活化某种矿物而影响浮选过程。磷矿浮选中,大量钙镁离子的存在会显著影响浮选,浮选效果变差。通过添加钙镁离子浮选试验,接触角、吸附量的测定及傅立叶红外光谱测试,结果表明：一定浓度的Ca₂ 、Mg₂ 离子会显著降低胶磷矿纯矿物的回收率,原因是在碱性矿浆中,钙镁浓度太高时,易生成氢氧钙(镁)的溶胶或沉淀,吸附于矿物表面,致使矿物表面有效成份油酸络合物减少,捕收剂吸附量降低,疏水性减弱,胶磷矿浮选效果变差。     

混合捕收剂浮选难选钛铁尾矿

研究了油酸钠、硬脂酸钠和现场混合药剂FH三种捕收剂单独及混合作用于钛铁矿纯矿物、人工混合矿的浮选行为。探究了混合捕收剂对六安钛铁尾矿浮选行为的影响。结果表明 油酸钠与硬脂酸钠混合以及油酸钠与FH混合后浮选效果增强, 产生正协同作用, 药剂的最佳混合比例分别为7∶3和5∶5。当钛铁矿矿浆浓度为40%, FH油酸钠混合药剂用量为750 g/t, 硫酸用量为1 250 g/t 时, 钛铁矿回收率和品位分别为67.14%和32.60%, 相比单独使用两种捕收剂, 回收率分别提高了16.89%和8.97%, 品位分别提高了11.95%和6.02%。     

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。     

脂肪酸钠浮选盐类矿物的作用机理研究

本文通过ζ-电位测定,红外光谱分析,吸附量测定,浮选实验及溶液化学计算,研究了脂肪酸钠浮选盐类矿物的作用机理。结果表明,油酸钠在盐类矿物表面发生了化学吸附或表面反应,使盐类矿物表面负ζ-电位显著增加,油酸钠在盐类矿物表面的吸附行为与金属油酸盐生成的溶液化学条件有一致关系,磷灰石、萤石、重晶石、白钨矿、方解石浮选回收率显著上升所需捕收剂浓度,对应于表面脂肪酸钙(钡)沉淀生成所需脂肪酸钠的浓度。这表明,脂肪酸类捕收剂与盐类矿物的作用机理是表面化学反应生成金属脂肪酸盐沉淀。     

新型铁矿石反浮选捕收剂DLC-2浮选性能及机理

复配了一种以油酸(钠)为主要成分的混合捕收剂,并从接触角及红外光谱角度对其浮选铁矿石的机理进行了比较研究。开路浮选实验结果表明,与现场药剂相比,在精矿回收率相近的情况下,自配药剂(DLC-2)可获得铁含量为58.34%的精矿,高于现场药剂1.64个百分点。接触角测量结果显示,二氧化硅经氧化钙、淀粉和油酸钠接触改性后,接触角由65.5°增大到74.3°,疏水性能增强,易于与氧化铁分离;单矿物的FTIR测试结果表明,浮选药剂在氧化铁表面以物理吸附为主,在二氧化硅表面发生了化学吸附。     

微波预处理前后萤石浮选的动力学分析

为阐明微波对萤石浮选的影响机理,本文研究了微波预处理前后萤石浮选回收率、吸附量的变化规律,并进行不同微波预处理方式下的浮选动力学计算。浮选试验结果表明,与微波处理前相比,微波预处理纯矿物、去离子水、加捕收剂的矿浆后,萤石的浮选回收率均有所提高,而微波预处理矿浆,萤石的浮选回收率显著降低。油酸钠吸附量计算结果与萤石浮选回收率的大小顺序一致。而萤石的浮选动力学计算结果发现,微波预处理前后,萤石浮选动力学均符合一级动力学模型。微波预处理萤石纯矿物、去离子水、加捕收剂的矿浆不仅提高了萤石的浮选回收率,还加快了浮选速率,而微波处理矿浆则降低了萤石的浮选回收率和浮选速率。     

微波预处理对萤石浮选的影响机理研究

为研究微波预处理对萤石浮选的影响机理,分别对萤石纯矿物、去离子水、矿浆和添加捕收剂的矿浆进行微波预处理,研究不同pH值、捕收剂浓度、预处理时间和微波功率对萤石浮选回收率的影响.结果表明,在最佳试验条件下,微波预处理纯矿物、去离子水和添加捕收剂的矿浆后,浮选回收率有所提高,同时pH值调整剂及捕收剂用量均有所减少;而微波预...     

A new collector for rare earth mineral flotation

A new collector for bastnaesite flotation - modified hydroxamic acid (MOHA) has been developed through several years laboratory research. The experimental results of flotation of pure bastnaesite mineral and rare earth ores, and the application experience in flotation plants showed that MOHA is an efficient collector for bastnaesite flotation. MOHA has stronger collector ability and higher selectivity compared to the other commonly used collectors. Through the measurements of zeta-potential, adsorption and infrared adsorption spectrum and in terms of the electronegativity theory of reagent groups, the flotation mechanism has been discussed. It was concluded that the adsorption of MOHA on bastnaesite surfaces is chemical adsorption in nature through three oxygen atoms in the polar group of MOHA chelating the surface Ce(III) of bastnaesite to form a pentagon-cycle chelate: O---C=N---O---Ce(III)---). Additionally, the chemisorption is accompanied with the multilayer and non-homogeneous physical adsorption of the MOHA molecules. The MOHA adsorption equation at the surfaces of bastnaesite can be expressed as: Γ = 6.76×10⁻²C^1/1.02, while the adsorption rate constant k is: k = 2.64×10⁵min⁻¹mol⁻¹m².     

A mixed collector system for phosphate flotation

Flotation has been used in industry for more than a half century as the primary technique for upgrading phosphate. While the flotation of phosphate was inefficient when oleic acid was used alone as a collector, therefore a mixed collector of oleic acid (HOl), linoleic acid (LA) and linolenic acid (LNA) was employed to improve the recovery of phosphate flotation. The batch flotation results showed that the optimal composition of the mixed collector was 54 wt.% HOl, 36 wt.% LA and 10 wt.% LNA. Additionally, the effect of pH on the mixed collector application was studied while considering the surface tension, contact angle and micro-flotation. The results showed that the mixed collector should be used at a pH of 9.5. Above a pH of 9.5, the adsorption of fatty acids dimers on the apatite surface hindered phosphate flotation. The influence of the mixed collector assembly on apatite flotation was also investigated. It was demonstrated that due to its low critical micelle concentration, a sufficiently hydrophobic apatite surface could be generated at a collector concentration of 60 mg/L. In addition, zeta potential experiments suggested that collector adsorption was governed by chemisorption. FTIR and XPS spectra studies further indicated that the chemical reaction involved the carboxyl groups of fatty acids and Ca species at the apatite surface for each fatty acid in the mixed collector.     

Technical note bench scale flotation of a brazilian monazite ore

Preliminary studies of the floatability characteristics of monazite, zircon and rutile, performed in a modified Hallimond tube, initiated a bench scale investigation of the flotation of a Brazilian monazite ore from Sao Goncalo do Sapucai, MG. The testwork was conducted with the utilisation of a commercial hydroxamate and sodium oleate as collectors and sodium metasilicate as depressant. In all tests, the best collector/depressant ratio defined during the microflotation experiments was confirmed at bench scale. The results indicated that with both collectors it is possible to produce a high purity cleaner monazite concentrate (> 60% RE₂O₃). The concentrations of collector and depressant must be well defined to prevent a significant increase in the flotation of gamgue minerals such as ilmenite, zircon and rutile, causing contamination of the monazite concentrate.     

The development of a composite collector for the flotation of rutile

A study was carried out to find a replacement for benzyl arsenic acid (BAA) that was used in the rutile flotation circuit of a hard rock rutile mine in China. Several types of oxide collectors were tested, including sodium oleate, sodium laurate, sodium dodecyl sulphate, amino acids, diphosphonic acid and styryl phosphonic acid. It was found that styryl phosphonic acid (SPA) was the most effective, and that an aliphatic alcohol (e.g., octanol) was required to maintain the effectiveness of SPA.However, octanol was insoluble in water. The composite collector that was mixed with SPA and octanol had to be well emulsified before addition to flotation pulp. Poorly emulsified composite collectors destroyed flotation froths. Several surfactants were tested as emulsifiers and one was found to have the least adverse effects on the selectivity of the composite collector. By using the composite collector that contained SPA, octanol and the emulsifier, a rutile rougher concentrate assaying 71.3% TiO₂ was floated at 81.6% recovery from a feed containing 8.78% Ti0₂ in a single stage rougher flotation.     

萤石矿新型低温浮选捕收剂性能的研究

对研制出的萤石矿低温浮选药剂进行了选矿试验研究。通过条件试验确定了新型药剂的浮选最佳pH值为6.25,捕收剂用量为1200g/L;新型药剂的耐低温性能较强,在16.5～43℃之间变化不大,保持了较好的捕收性能。在矿石较为难选和温度较低的条件下,新型药剂在流程试验中的回收率达到了65.90%,较油酸的回收率高近30%。条件试验和流程试验结果显示,所研制的药剂是一种新型高效的萤石矿低温浮选药剂。     

Application of flotometry for characterizing flotation in the presence of particles aggregation

Different size fractions of coarse magnetite were floated in water in a monobubble Hallimond tube with an increasing dosage of sodium oleate (Na01), diethyl dixanthate ((EtX)₂), and hexadecane. All maximum recovery (R_m) vs collector concentration curves plotted for various size fractions were similar in shape having zero recovery at a low and high collector concentration with a maximum recovery in between at a characteristic collector dosage c_m, which provides maximum hydrophobicity of the system. Properties of the studied flotation system and literature data indicated that the cessation of magnetite flotation with a high dosage of Na01 is due to hydrophilic layers of oleate ions sorption, while in the other two systems it is due to oil agglomeration of the solids. The values of the maximum particle size which can still be floated (a^m₅₀), taken from the maximum recovery vs particle mean size at the concentration equal to c_m and R_m=50%, seems to be the parameter which well characterizes any solid-collector-water flotation system because this value derives mainly from the hydrophobic properties of the flotation system and particle density in water, ^′. The a^m₅₀ value and the so-called “flotometry equation” (for our Hallimond tube in the form L_m = a^m₅₀^′) were used for calculation of the parameter L_m which in turn was used for a comparison of the floatability of magnetite with different collectors and subsequently with other flotation systems. The values of parameter L_m indicated that magnetite floatability increases in the order: collectorless (mechanical carryover), flotation with (EtX)₂, flotation in the presence of hexadecane, and oleate flotation. It was established that the floatability of magnetite with Na01 is equal to the floatability of galena with (EtX)₂ and very similar to the collectorless floatability of Teflon. Floatability of the above three systems is most likely the maximum possible floatability of a solid in an aqueous environment.     

动力煤反浮选试验研究

针对亚烟煤煤泥反浮选过程中阳离子捕收剂耗量大的缺陷，自制DTAC(十二烷基三甲基氯化铵)/脂肪酸(正辛酸、正癸酸、月桂酸、十四酸、十六酸)复配型捕收剂替代传统阳离子捕收剂DTAC。研究了各复配型捕收剂的界面性质，并通过单元浮选试验对DTAC和复配型捕收剂浮选性能进行了比较。表面张力测试和捕收剂在气泡表面的吸附量测试表明复配型捕收剂具有更高的表面活性且更容易吸附在气液界面；复配型捕收剂具有更强的捕收能力且随着复配捕收剂中脂肪酸碳链长度的变化而变化；分别采用DTAC和复配捕收剂进行浮选试验。试验结果表明，当C12(DTAC/十二酸)型复配型捕收剂用量为1.66 kg/t(不考虑脂肪酸)时，浮选指标与单独使用3.32 kg/t的 DTAC时相近，降低了约50%DTAC耗量，大大降低了浮选成本。     

Potash flotation practice for carnallite resources in the Qinghai Province,PRC

Two potash plants at the Qarhan Salt Lake in Qinghai Province, Peoples Republic of China, were visited in July 2012 to discuss processing strategies, particularly flotation technology. The first plant, operated by Qinghai Avic Resources Co., Ltd., in Mahai, is using the traditional KCl flotation from NaCl with an amine as collector after selective decomposition of carnallite (KCl.MgCl₂⋅6H₂O). The second plant is operated by the Qinghai Salt Lake Group in Geermu where NaCl is floated from carnallite with an alkyl-morpholine as collector prior to carnallite decomposition for KCl production. These two major potash flotation technologies being used in the Qinghai Province of the Peoples Republic of China are reviewed and discussed with respect to recent research findings regarding the use of alkyl-morpholine collectors in reverse flotation of NaCl from carnallite.     

柠檬酸对铌铁矿和石英浮选分离的影响

柠檬酸是氧化矿和脉石矿物浮选分离中非常有效的抑制剂。针对白云鄂博矿中铌矿物难以回收的现状,使用OHA作为捕收剂,六水氯化铁为石英活化剂,柠檬酸为抑制剂,研究抑制剂对铌铁矿和石英的浮游特性的影响。柠檬酸作为抑制剂对铌铁矿和石英人工混合矿的最佳浮选分离条件：OHA用量为0.05 mmol/L,六水氯化铁用量为20 mg/L,柠檬酸用量为0.1 mmol/L,pH=9,获得的铌铁矿精矿中Nb₂O₅回收率为76.03%、Nb₂O₅品位为58.38%,实现了铌铁矿和石英的高效浮选分离。采用Zeta电位、接触角测试、X射线光电子能谱分析(XPS)揭示了药剂在矿物表面的作用机理,为铌铁矿和石英的高效分离提供理论依据,并为将其应用到实际生产中提供技术支撑,同时丰富铌铁矿浮选抑制剂体系。     

Ionic strength effects in diamine flotation of quartz and magnetite

The flotation of quartz and magnetite was studied as a function of pH when using N-alkyl-1, 3 diaminopropanes and n-dodecylamine as collectors. The alkyl chains of the diamines were 8, 12 and 16 carbons in length. Two collector concentrations were used and flotation studied in the absence of additives and in the presence of NaCl. The chain length effect on flotation using the diamines is comparable to that observed in flotation using monoamines. All the amines are relatively stronger collectors for quartz than for magnetite. The NaCl, in the concentration studied, 0.6 kmol/m³, functions as a depressant for the minerals. The 12 C diamine is a stronger collector for the minerals than the 12 C monoamine. Probable surface chemical phenomena giving rise to the observed experimental results are discussed.