Gemini双季铵盐捕收剂BDDA和EDDA对高岭石、叶腊石、伊利石浮选行为的比较及机理

采用了新型Gemini双季铵盐捕收剂丁烷-1,4-双十二烷基二甲基溴化铵（BDDA）和乙烷-1,2-双十二烷基二甲基溴化铵（EDDA）对比研究了其对高岭石、叶腊石、伊利石的浮选行为及作用机理。单矿物试验结果表明,在广泛的pH范围内,新型Gemini双季铵盐捕收剂BDDA和EDDA对三种铝硅酸盐矿物具有优异的捕收性能,且BDDA的捕收能力强于EDDA。红外光谱和动电位研究表明,Gemini双季铵盐捕收剂对三种铝硅酸盐矿物的作用机理为静电吸附和氢键作用。采用DFT密度泛函理论,在B3LYP／6—31G（d）水平上对捕收剂阳离子BDDA2＋和EDDA2＋进行量化计算,结果表明BDDA的捕收能力强于EDDA。这与单矿物浮选结果、动电位测定结果一致。     

Comparative studies on flotation of illite, pyrophyllite and kaolinite with Gemini and conventional cationic surfactants

To search a novel class of effective silicate mineral collectors, the Gemini quaternary ammonium salt surfactant (butane-α, ω-bis(dimethyl dodeculammonium bromide), 12-4-12) and its corresponding conventional monomeric surfactant (dedecyl trimethyl ammonium bromide, DTAB) were adopted to comparatively study the flotation behaviors of illite, pyrophyllite and kaolinite. Three silicate minerals with the Gemini surfactant as collector reveal floatability far better than with the corresponding traditional one. At pH 6, the best recoveries of illite, pyrophyllite and kaolinite with 3.5×10-4 mol/L 12-4-12 are 99.2%, 91.7% and 99.6%, respectively. The fluorescence and contact angle measurement were also conducted for the further investigation of surfactants aggregation behavior and silicate mineral surface hydrophobic properties. FTIR spectra analysis and electrokinetic analysis show that the mechanism of adsorption of collector molecules on mineral surfaces is almost identical for the electronic attraction and hydrogen bonds effect. The superior collecting power of dimeric collector may be attributed primarily to its special structure and its essential properties.     

Effect of modified starches on depression of diaspore

Four modified starches with selected charge characteristics including cationic starch (CAS), carboxymethyl starch (CMS), amphoteric starch (AMS) and soluble starch (SS) were investigated as depressants for diaspore in reverse flotation test using cationic collector (dodecylamine). Adsorption examination, Zeta potential measurement and Fourier transform infrared (FTIR) spectroscopy were used to clarify the role of the surface charge characteristics of starches in determining the adsorption behavior and depression performance as well as the mineral-starch interaction. Results show that the positively charged starches (CAS and AMS) display higher adsorption amounts and also better depression performance compared with the non-ionic (SS) and anionic starch (CMS), benefiting from the favorable electrostatic attraction with diaspore and also electrostatic repulsion with collector. FTIR spectroscopy proves the presence of hydrogen bonds and chemical complexation between mineral and starches in an integrated manner.     

捕收剂的分子设计与绿色合成

捕收剂是矿物浮选分离过程中必不可少的药剂,研究捕收剂的分子设计与绿色合成对于提高浮选技术水平具有重要意义。综述近年来中南大学钟宏教授课题组在捕收剂的分子设计、绿色合成与浮选机理研究方面的系列成果。研究开发溶剂法合成黄原酸盐等硫化矿捕收剂的绿色合成技术,提高合成效率,改善生产环境。设计并合成异丁基黄原酸苯甲酰基酯等多种新型硫化矿捕收剂、Gemini双季铵盐等多种新型非硫化矿捕收剂及N,N-二丁基二硫代氨基甲酸乙羟肟酸等硫化?氧化矿双功能捕收剂,此外还研究选矿药剂之间的组合用药。     

Reverse flotation separation on diaspore and kaolinite in the presence of cationic polyacrylamide polymers

1　INTRODUCTIONChinaisrichindiasporebauxiteresources[1,2 ]whichpossessspecialpropertiessuchashighgradeofbothAl2 O3andSiO2 andlowFecontent,buttheAl/Si(massratioofAl2 O3toSiO2 )valueislow .Inordertotreatthediasporebauxite ,unitedmethodsandsin teringmethods[3] arestillappliedalthoughsufferingfromdisadvantagesincludingcomplextechnologyflowchart,highenergyconsumption ,highproduc tioncost ,andrestrainingfurtherdevelopmentofalu minaindustry .However ,byimprovingbauxiteAl/Si>10 ,wecanchoosem…     

捕收剂RL在铝土矿浮选中的应用

研究了一水硬铝石、高岭石及叶腊石等单矿物在RL为捕收剂时的浮选特性,考察了各种调整剂、难免离子对浮选体系的影响,在此基础上进行了人工混合矿和实际矿石的分离试验。实际矿石闭路试验结果表明：采用RL为捕收剂,碳酸钠和六偏磷酸钠为调整剂,精矿中Al2O3和SiO2的品位分别为70．74％和6．37％（精矿铝硅比为11．11）,Al2O3的回收率达到90．52％。     

Improvement of flotation behavior of Mengzi lead-silver-zinc ore by pulp potential control flotation

The electrochemical behavior of Mengzi lead-silver-zinc ore flotation system was studied. Based on the electrochemical characteristics of sulfide mineral flotation system, a stage potential control flotation was developed with the main parameters of pulp potential（φp）, pH value and collector dosage. Using N,N＇ diphenylamino-dithiolphosphoric acid（NNDDC） as a collector, which has good selectivity for galena flotation at pH 8.8 and pulp potential 330 mV, DDTC is used as secondary collector to improve both the grade and recovery of Pb and Ag. The pulp potential values significantly influence the floatability of practical minerals and single minerals when using NNDDC as the collector. The flotation recovery of galena reaches 85% at about 0.3 V and pH8.8. With the usage of pulp potential control during grinding and flotation, the new pulp electrochemical technology for Mengzi lead-silver-zinc ore flotation was developed. The results show that the grades of Pb and Ag of galena concentrate are 55% and 1 800 g/t, respectively, while the recoveries of Pb and Ag are 86.5% and 65%, respectively, the grade of Zn of marmatite concentrate is 42.5%, and the recovery of Zn is 91.25%.     

Nature of (001) and (001) faces and flocculation flotation of kaolinite

Flotation mechanism of kaolinite was investigated through flotation test, SEM analysis and quantum chemical simulation calculation. It is shown that the (001) face of kaolinite easily adsorb cationic collector to exhibit hydrophobicity; the (001) face is easily interacted with the reagent carrying the group of high electronegativity (-O-,-N-, F-) to show hydrophilicity. The cationic and anionic polyacrylamide are adsorbed onto the (001) face of kaolinite and the flocculation of kaolinite particles may take place; the (001) faces are exposed to interact with cationic collector to be rendered hydrophobicity. Thus, the macromolecules can evidently enhance the flotation of kaolinite in alkaline media.     

Nature of (001) and (00) faces and flocculation flotation of kaolinite

1　INTRODUCTIONThediasporicbauxiteresourceinChinaischar acterizedbyhighcontentofAl2 O3andSiO2 andlowmassratioofAl2 O3toSiO2 ,theratioisusually 5 8.ThediasporicbauxitewithlowmassratioofAl2 O3toSiO2 cannotbedirectlyprocessedbyBayer’stechnol ogy .ThesinteringorcombinationofsinteringandBayerprocessareoftenusedtotreatsuchdiasporicbauxite ,showingenergy intensiveandenvironmentalunfriendly[1] .ItisrequiredtoincreasethemassratioofAl2 O3toSiO2 toabove 10byphysicalseparationsothattheBayer…     

新型捕收剂作用下赤铁矿与胶磷矿的分选及机理(英文)

对新研制的反浮选降磷捕收剂(RFP138)体系中赤铁矿和胶磷矿的可选性及作用机理进行研究。赤铁矿和胶磷矿的单矿物及人工混合矿的反浮选分离试验表明:RFP138是赤铁矿和胶磷矿的良好捕收剂,在碱性条件下采用合适的抑制剂,能够有效地实现两种矿物的分选,将P含量由人工混合矿中的1.05%降至0.12%,且TFe的回收率达到91.30%。对RFP138溶液的化学行为及红外光谱进行分析,探讨RFP138对两种矿物选择性捕收的机理。     

Flotation Separating Rutile from Calcium and Silicon Gangue Minerals

Rutile is an imPortant drineral in extractionmetal titanium and for mdeng titanium white(dioxide)[l]. Natural rutile comPoses of sea-shore placer and natural ores. Relatively, Chinais short of seashore placer which contains richrutile[2-], so it is very necessary to developand use the natural ores resource.There are always certain amounts of calciumand silicon gangue hanerals associated withnatural rutile ores, which is a vital restrictingfactor of raising the grade of rutile concentrates[5].…     

油酸钠对一水硬铝石和高岭石的捕收机理

用油酸钠为捕收剂,研究了一水硬铝石和高岭石的可浮性,并对捕收剂与矿物的作用机理进行了探讨,结果表明：油酸钠对一水硬铝石和高岭石的捕收主要由两方面因素控制,在pH4-7范围内,为化学反应起主要作用,在pH7-10以形成离子-分子缔合物为主要因素,在以油酸钠为琢收剂时,矿物表面活性Al^3 数量的不同导致了高岭石和一水硬铝石的可浮性差异,这为铝土矿正浮选脱硅提供了理论依据。     

QUANTUM CHEMISTRY ON FLOTATION BEHAVIOR OF KYANITE-GROUP POLYMERPHOUS MINERALS

ＱＵＡＮＴＵＭＣＨＥＭＩＳＴＲＹＯＮＦＬＯＴＡＴＩＯＮＢＥＨＡＶＩＯＲＯＦＫＹＡＮＩＴＥ－ＧＲＯＵＰＰＯＬＹＭＥＲＰＨＯＵＳＭＩＮＥＲＡＬＳ￥Ｄｏｎｇ，Ｈｏｎｇｊｕｎ；Ｃｈｅｎ，Ｊｉｎ（ＤｅｐａｒｔｍｅｎｔｏｆＭｉｎｅｒａｌＥｎｇｉｎｅｅｒｉｎｇ，Ｃ...     

氯化钠对铝硅矿物浮选的影响及其作用机理

采用季铵盐DTAL作捕收剂,研究了氯化钠对一水硬铝石和叶蜡石浮选的影响及其作用机理.随着氯化钠浓度的增加,叶蜡石的浮选回收率显著提高,而一水硬铝石的可浮性受其影响很小.机理研究表明:氯化钠对一水硬铝石的zeta-电位没有影响,而能显著降低叶蜡石的zeta-电位,增强捕收剂与叶腊石的静电作用,促进捕收剂的吸附而活化其浮选;叶蜡石表面电位的降低是因为氯离子对叶蜡石存在选择性吸附作用并对其结构进行插层,使得叶蜡石的层间距从0.93 nm增大至1.40 nm.溶液化学计算表明:氯化钠改变溶液的离子强度,显著降低了季铵盐阳离子表面活性剂的临界胶束浓度,使得吸附了捕收剂的矿物表面更容易疏水上浮.     

混合捕收剂浮选锂辉石的应用及作用机理

通过浮选试验,研究十二烷基磺酸钠、十二烷基硫酸钠、油酸、731、环烷酸皂,以及油酸与十二胺的混合捕收剂对锂辉石、长石和石英单矿物浮选行为及锂辉石实际矿石浮选指标的影响。借助Zeta电位、红外光谱分析、吸附量测试及量子化学计算,探讨混合捕收剂的作用机理。结果表明:油酸与十二胺的混合捕收剂,兼有捕收性和选择性好的特点,在碱性条件下能实现锂辉石与长石和石英的浮选分离。混合捕收剂在锂辉石表面的吸附量大于长石和石英。混合捕收剂中油酸在矿物表面以化学吸附为主,十二胺则以物理吸附为主。油酸离子分别与十二胺离子(或分子)和油酸分子以缔合形态存在,油酸的头基COO^-与锂辉石表面的Al原子发生化学作用。     

新型阳离子捕收剂在极难选高硅型铝土矿反浮选中的应用

详细研究了一水硬铝石和脉石矿物在BS-3为捕收剂时的浮选特性,考察了调整剂在矿浆中对浮选的影响,并在此基础上进行了人工配矿和实际矿石的浮选分离试验研究。实际矿石试验结果为:精矿中Al2O3和SiO2的品位分别为64.55%和6.28%,精矿A/S为10.28,Al2O3的回收率高达83.41%。     

Recent development in researches of electrochemistry of sulphide flotation at Central South University of Technology

1　ＣＯＬＬＥＣＴＯＲＬＥＳＳＦＬＯＴＡＴＩＯＮ1.1　ＮａｔｕｒａｌｆｌｏａｔａｂｉｌｉｔｙＴｈｅｉｎｈｅｒｅｎｔｈｙｄｒｏｐｈｏｂｉｃｉｔｙｏｎｃｅｔｈｏｕｇｈｔｔｏｂｅｔｙｐｉｃａｌｏｆｓｕｌｆｉｄｅｓ[1] ｉｓｎｏｗｔｈｏｕｇｈｔｔｏｂｅｒｅｓｔｒｉｃｔｅｄｔｏｓｕｌｆｉｄｅｓｓｕｃｈａｓｍｏｌｙｂｄｅｎｉｔｅａｎｄｏｔｈｅｒｍｉｎｅｒａｌｓｏｒｃｏｍｐｏｕｎｄｗｉｔｈｓｐｅｃｉａｌｓｔｒｕｃｔｕｒａｌｆｅａｔｕｒｅｓ .Ｍｉｎｅｒａｌｓｓｕｃｈａｓｍｏｌｙｂｄｅｎｉｔｅ ,ｏｒｐｉｍｅｎｔ ,ｒｅ…     

变性淀粉在铝硅矿物浮选分离中的作用机理

通过浮选实验、动电位和红外光谱测定,详细考察了变性淀粉在铝硅矿物浮选分离中的作用效果和机理。浮选实验显示：非离子淀粉和阴离子淀粉在pH＜6时,抑制一水硬铝石的浮选,但当pH＞6时,却对一水硬铝石浮选有活化作用;阳离子淀粉在较宽pH值范围内对一水硬铝石均有抑制作用;3种淀粉化合物在pH＜6时均活化高岭石的浮选,当pH＞6时活化作用较微。结果表明：变性淀粉是一水硬铝石型铝土矿反浮选中实现一水硬铝石和高岭石分离的有效调整剂,阴离子淀粉使矿物表面ζ电位更负,阳离子淀粉使矿物质表面ζ电位更正,非离子淀粉使矿物表面电位绝对值减小。由实验结果结合药剂与矿物作用前后的红外光谱分析,得出结论：非离子淀粉主要通过氢键作用吸附于矿物表面,而静电力和化学键合力在阴离子淀粉和阳离子淀粉吸附中发挥着重要作用。     

纳米比亚某含银硫化铜矿选矿试验研究

纳米比亚Karas矿区罗雷铜矿区的原生矿铜主要以黄铜矿、斑铜矿等硫化铜矿物形式存在,银分别以银黝铜矿为主的独立银矿物和以黄铜矿为载体的载体银矿物形式存在,铜、银品位分别为0.60%和3.03 g/t。浮选试验结果表明,矿样适当细磨至-0.074 mm占80%,以石灰做调整剂,Z200做捕收剂,在矿浆pH值为8的条件下,可获得铜品位22.3%,银品位61.8 g/t的含银铜精矿,铜、银回收率分别为90.6%和51.8%。     

某含银高硫铜矿的综合回收试验

某含银高硫铜矿含铜0.76%、硫24.35%及银34.92 g/t，有价矿物种类多、矿石性质复杂，采用抑硫优先浮选铜-活化浮选硫的原则工艺流程进行试验，配合石灰作为硫化铁矿物抑制剂以及筛选出丁基黄药+酯-105作为硫化铜矿物的组合捕收剂，强化了银在铜精矿中的富集。在选定工艺条件下，可获得铜品位21.60%、银品位602.84 g/t的铜精矿(铜和银回收率分别为89.30%和54.39%)，硫品位45.60%、银21.55 g/t的硫精矿(硫和银回收率分别为89.79%和29.59%)，实现了铜、硫和银的综合回收利用。