Interaction and flotation of diaspore with alkylamine hydrochlorides

ＩＮＴＲＯＤＵＣＴＩＯＮＦｌｏｔａｔｉｏｎｉｓｏｎｅｏｆｔｈｅｍｏｓｔｖｅｒｓａｔｉｌｅｔｅｃｈｎｏｌｏｇｉｅｓｕｓｅｄｉｎｍｉｎｅｒａｌｐｒｏｃｅｓｓｉｎｇ .Ｔｈｅｓｅｐａｒａｔｉｏｎｏｆｍｉｎｅｒ ａｌｓｂｙｆｌｏｔａｔｉｏｎｈａｓｂｅｅｎｐｒｏｖｅｎｅｆｆｅｃｔｉｖｅｗｈｅｎｐａｒｔｉ ｃｌｅｓｔｏｂｅｆｌｏａｔｅｄｃａｎｂｅｍａｄｅｓｅｌｅｃｔｉｖｅｌｙｈｙｄｒｏｐｈｏ ｂｉｃ .Ｔｈｅｈｙｄｒｏｐｈｏｂｉｃｉｔｙｉｓｏｆｔｅｎｉｎｄｕｃｅｄｂｙｔｈｅａｄ ｓｏｒｐｔｉｏｎｏｆｃｏｌｌｅｃｔ…     

Effect of hydroxamic acid starch on reverse flotation desilicate from diasporic bauxite

It is important to depress diaspore effectively in order to remove silicates from diasporic bauxite.A new water soluble polymer hydroxamic acid starch(HA-starch)was prepared.The effects of the product on the diaspore and kaolinite flotation were investigated and its reactive mechanism was studied by zeta potential measurement and FTIR.The results show that HA-starch can depress diaspore while make positive effect on kaolinite flotation at low pH value(pH below 6)The flotation recovery of diaspore was sharply decreased with the increase of concentration of HA-starch.The chemical adsorption of HA-starch on the surface of diaspore was revealed.     

硬质和软质高岭石的晶体结构与浮选行为

研究了硬质与软质高岭土中的高岭石晶体结构、晶体形态与表面性质之间的关系及其对浮选行为的影响。硬质和软质高岭土表面Zeta电位随pH值的变化规律基本相同,具有相近的表面零电点（PZC）值。几种硬质高岭土的PZC值的变化范围为2．5－3．8。在较宽的pH值范围,软质高岭土比硬质高岭土的电位高。铝土矿中高岭石以硬质高岭石为主,结晶有序度低,与药剂作用不强,可浮性较软质高岭石差,在铝土矿反浮选中,需强化对高岭石的捕收作用。     

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。     

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。     

Aluminum-silicates flotation with quaternary ammonium salts

1　INTRODUCTIONThediasporic bauxiteinChinaisdifferentfromthegibbsite bauxiteandboehmite bauxiteinothercountriesbyitshighcontentofAl2 O3andSiO2 andlowmassratioofAl2 O3toSiO2 (massratioofAl2 O3toSiO2 =A/S ,usually5 6 ) .Theproductioncostofa luminumoxidefromsuchrefractorybauxiteby“sin tering”or“combining”technologiesismuchhigherthanthatbyBayer sprocess .Sothatthealuminum silicateganguessuchaspyrophyllite ,illiteandkaolin iteinthebauxiteisneededtoberemovedtoincreaseA/S .Hussainetal…     

Cleavage nature,electrokinetics,aggregation and dispersion of kaolinite

1　INTRODUCTIONKaoliniteiscurrentlyusedinceramics ,papermanufacturing ,medicalapplications ,agriculturalchemicals ,chemicalengineering ,refractorymaterialanddefenseindustrybecausekaolinitehasmanyhighprocessingpropertiesasanindustrialmineralduetoitssurfaceproperties[1,2 ] .Inreverseflotationofdi asporicbauxite ,whichisveryimportantforthein dustryofaluminumoxideproduction ,kaoliniteisneededtoberemoved .Therefore ,Itisusefultoun derstandthecrystalstructure ,cleavagenature ,sur faceelectrokin…     

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.     

使用抑制剂甘油基黄原酸钠浮选分离铁闪锌矿与黄铁矿(英文)

研究抑制剂甘油基黄原酸钠(SGX)在铁闪锌矿与黄铁矿浮选分离过程中的作用机理。通过浮选实验考察该抑制剂对硫化矿物的浮选抑制行为。结果表明,用丁黄药作捕收剂,在SGX存在下铁闪锌矿能被Cu2+活化从而具有良好的可浮性,而黄铁矿不能被Cu2+活化;在pH为4-11的范围,SGX的用量小于50mg/L时,可以实现两种矿物的选择性分离。动电位分析表明,SGX在Cu2+存在的条件下不能阻止丁黄药的阴离子在铁闪锌矿表面的吸附,但能阻止丁黄药的阴离子在黄铁矿表面的吸附。吸附等温测试结果表明,SGX在黄铁矿表面的吸附量远比在铁闪锌表面量大。     

Flotation evaluation and adsorption mechanism of medialan collector to wolframite

Medialan has preferable flotation performance to wolframite,under the conditions of the best flotation pH value 7.0 and low dosage,wolframite recovery is up to80%.Medialan shows poor flotation performance to quartz,but better to fluorite and calcite.However,fluorite and calcite are inhibited in a certain degree by adding medialan mixed with sodium silicate.Adsorption mechanism of medialan collector on wolfram surface was also studied by using infrared(IR)radiation spectrum,adsorption volume,and zeta potential.The results show that medialan can adsorb on wolfram surface in the form of chemistry adsorption,and as medialan collector dosage changes,change law of adsorption volume is similar with that of wolfram pure mineral flotation.Zeta potential results prove that zeta potential of wolfram surface moves negatively after adsorbing medialan collector.     

Prediction of edge energy level at mineral-solution interface by means of zeta potential

1　ＩＮＴＲＯＤＵＣＴＩＯＮＳｉｎｃｅ 192 5,Ｋｅｌｌｅｒｆｏｕｎｄｘａｎｔｈａｔｅａｓｅｆｆｅｃｔｉｖｅｃｏｌｌｅｃｔｏｒｆｏｒｓｕｌｆｉｄｅｍｉｎｅｒａｌｓ ,ｆｌｏｔａｔｉｏｎｂｅｇａｎｔｏａｐｐｌｙｉｎｔｈｅｉｎｄｕｓｔｒｙｏｆｍｉｎｅｒａｌｐｒｏｃｅｓｓｉｎｇｏｎａｌａｒｇｅｓｃａｌｅ ,ｉｔｂｅｃａｍｅｏｎｅｏｆｔｈｅｍａｉｎｏｒｅｄｒｅｓｓｉｎｇｍｅｔｈｏｄｓ .Ａｓａｃｏｌｌｅｃｔｏｒ,ｘａｎｔｈａｔｅｈａｓｌｏｗｄｏｓａｇｅ ,ｂｅｔｔｅｒｓｅｌｅｃｔｉｖｉｔｙａｎｄｈｉｇｈｒｅｃｏｖｅ…     

直链烷基胺浮选铝硅矿物机理

研究了一水硬铝石和高岭石、叶蜡石及伊利石等几种含铝硅酸盐矿物在不同pH条件下的动电行为与浮选行为。一水硬铝石、高岭石、叶蜡石及伊利石的等电点（IEP）分别为pH6．2,4．3,2．0,3．4。在pH＞IEP时,烷基胺类阳离子捕收剂主要以静电作用吸附在一水硬铝石矿物表面,其浮选高岭石等3种铝硅酸盐矿物的可浮性大小顺序是叶蜡石＞高岭石＞伊利石。高岭石、叶蜡石和伊利石均是层状硅酸盐矿物,其破碎磨细时,将沿层间断裂,由于晶体结构的原因其层面荷负电荷。烷基胺类阳离子捕收剂以静电作用力吸附于铝硅酸盐矿物表面的层面使矿物疏水上浮。     

季铵型阳离子捕收剂在一水硬铝石和高岭石表面的吸附机理

研究十二烷基三甲基氯化铵（DTAC）和十六烷基三甲基氯化铵（CTAC）对一水硬铝石和高岭石的浮选行为。通过残余浓度法测定吸附等温线,荧光探针法和Zeta电位测试方法研究季铵型阳离子捕收剂在矿物表面的吸附机理。浮选结果表明：将DTAC和CTAC作为捕收剂,一水硬铝石的浮选回收率随着pH的增大而增加,而高岭石的浮选回收率随着pH的增大反而下降。当捕收剂的碳链增长时,矿物浮选回收率提高,但高岭石的增加幅度小于一水硬铝石的。在低浓度范围内,阳离子表面活性剂通过静电作用吸附在一水硬铝石表面,而对于高岭石,还存在离子交换作用。当浓度增大时,阳离子表面活性剂通过碳链间疏水缔合作用在两种矿物表面进一步吸附。矿物表面微极性研究表明：CTAC的疏水性比DTAC强,相同溶液浓度下CTAC在一水硬铝石表面能形成比在高岭石表面更大的胶团,这也说明阳离子表面活性剂碳链的增长对一水硬铝石吸附的影响要大,与浮选结果相吻合。     

Swelling of clay minerals in ammonium leaching of weathered crust elution-deposited rare earth ores

The effect of hydrated radius, cation valence, pH and solution concentration on the zeta potential of clay minerals was investigated, and the relation between zeta potential of clay minerals and swelling was discussed in different leaching agents as well. The results show that the zeta potential of clay minerals decreases with the hydrated ionic radius increasing. It could be seen that the zeta potential of the clay minerals in AICl_3 solution is positive,whereas that in NH_4C1, KCl and MgCl_2 solution is negative. And the zeta potential of clay minerals increases with the cation valence increasing. Moreover, the zeta potential of clay minerals decreases with the solution pH increasing,whereas that increases with the solution concentration increasing in different ammonium solutions. In addition,the swelling of clay minerals decreases while the zeta potential of clay minerals increasing in different ammonium solutions. The ability of compound ammonium to inhibit the swelling of clay minerals is lower than that of single ammonium solution.     

Mechanism and application on sulphidizing flotation of copper oxide with combined collectors

The effect of sodium butyl xanthate (NaBX) and dodecylamine (DDA) as combined collector on the sulphidizing flotation of copper oxide was investigated by flotation test, fluorescent pyrene probe, zeta potential, and infrared spectroscopy analyses. The micro-flotation results show that combined use of NaBX+DDA yields better effect than using NaBX at pH 7-11 only, and the optimal molar ratio of NaBX to DDA is 2: 1. The actual ores flotation shows that when the dosage of NaBX+DDA is (100+54) g/t, the copper concentrate grade and recovery are 15.93% and 76.73%, respectively. The fluorescent pyrene probe test demonstrates that the NaBX+DDA can reduce the micelle concentration in the pulp. The zeta potential and the infrared spectroscopy analyses indicate that chemical adsorption, hydrogen-bonding and electrostatic interaction can help to adsorb NaBX+DDA on the surface of malachite. Meantime, copper xanthate and copper-amine complexes may be generated during the adsorption process.     

无捕收剂浮选时硫化矿物表面的疏水—亲水平衡关系

通过硫化矿物表面中性硫(S~o)的溶剂提取-化学分析、矿浆电位测定和浮选试验,建立了自诱导浮选和硫化钠诱导浮选的疏水-亲水平衡关系,分别用[S~o]/[OH~-]和[S~o]/[OH~-]+[HS~-])表示S~o的生成量[S~o]受矿浆电位调控研究结果表明,pH值相同时,[S~o]值越大,矿物表面疏水性高,浮选行为好pH值高,[OH~-]值高,矿物表面亲水性大,浮选需要的[S~o]多;反之亦然同一pH值下,硫化钠诱导浮选所需[S~o]较自诱导浮选高     

Flotation of aluminosilicate minerals using alkylguanidine collectors

The flotation mechanism of aluminosilicate minerals using alkylguanidine collectors was studied through flotation experiments, Zeta potential measurements and FT-IR spectrum analysis. It is shown that kaolinite, illite and pyrophyllite all exhibit good floatability with alkylguanidines as collectors at pH 4-12. The flotation recoveries rise with the increase of the carbon chain length. Isoelectric point(IEP) is determined to be 3.5, 3.0 and 2.3 for kaolinite, illite and pyrophyllite, respectively. However, it is anomalous that the presence of cationic collectors has less influence on the negatively charged mineral surfaces. It is explained by the special structure of guanidine which is one of the strongest bases, having two -NH2 groups. One of them maybe interacts with minerals by electrostatic forces, and the other maybe forms hydrogen bonding with OH- ions on the aluminosilicate surfaces or in the aqueous solution, increasing the density of negative charge on the aluminosilicate surface and leading unpronounced positive charge to increase on the aluminosilicate. By combining the flotation tests, Zeta potential and FTIR measurements above, the interaction mechanism can be concluded. The simultaneous presence of cationic and neutral amine groups makes it possible for SAG cation to bind on three aluminosilicate minerals by both electrostatic attraction and hydrogen bonding. While in acidic medium, the interaction of the alkylguanidines on the aluminosilicate surfaces is mainly by means of electrostatic force and hydrogen bond; in the alkaline medium, it is by the way of electrostatic effect and hydrogen bond.     

Evolution of PZC with thermal transformation of Tunisian kaolinite

The purpose of this paper is to study the thermal behaviour of Na⁺-saturated Tunisian kaolinite (ka-Tab) with the evolution of its point of zero charge (PZC). The Fourier Transform Infrared spectroscopy (FTIR), X-Ray Diffraction (XRD), Differential Thermal Analysis (DTA), Cation Exchange Capacity (CEC) and specific surface area (SSA) were used to characterize the kaolinite sample. In the present investigation, the focus was on the surface charge characteristics of kaolinite at different temperature of heating. The results show that the formation of new phases in the kaolinite structure at temperature >500–600°C, shifts the PZC value towards 8 which approximately PZC value of α-Al₂O₃. The article is published in the original.     

金属阳离子在锂辉石浮选中的活化行为及作用机理

在油酸浮选锂辉石体系中分别加入Ca^2+、Al^3+、Fe^3+离子,通过单矿物浮选试验、金属离子吸附量检测、金属离子水解组份浓度计算、矿物表面动电位测试、红外光谱检测以及量子化学模拟计算研究Ca^2+、Al^3+、Fe^3+离子对锂辉石浮选的活化行为和作用机理。结果表明:Ca^2+离子的最佳活化区间为pH大于12的强碱性条件,Al^3+离子的最佳活化pH为6.47,而Fe^3+离子的最佳活化pH为7.25;在这些pH区间内,锂辉石浮选回收率和金属离子吸附量均达到最大值。在锂辉石浮选过程中起活化作用的有效组份为它们分别对应的氢氧化物沉淀。Ca^2+、Al^3+、Fe^3+离子可使锂辉石表面动电位向正值方向显著偏移;Ca^2+离子在锂辉石表面双电层的外层发生静电吸附,Al^3+和Fe^3+离子在锂辉石表面双电层的内层发生特性吸附。钙原子与锂辉石矿物表面吸附后形成的Ca—O键的键强较小,以离子键为主;铁原子与矿物表面形成Fe—O化学键的键强较大,含有一定的共价键组份;而铝原子与矿物表面吸附后形成的Al—O键的键长、键强等参数介于钙、铁的参数之间。油酸在Ca^2+活化后的锂辉石表面发生了化学吸附和少量的物理吸附,而在Al^3+、Fe^3+活化后的锂辉石表面发生了较为强烈的化学吸附。     

硫化矿物的浮选电化学与浮选行为

研究黄铜矿、黄铁矿、方铅矿等矿物在有/无捕收剂两种情况下的浮选行为,考察浮选与矿浆电位的关系。结果表明:当pH值分别小于4.0时,黄铜矿无捕收剂浮选的电位区间为0~0.9 V;当pH值为4.0或11.0时,矿浆电位大于0.85 V以后,黄铁矿的浮选回收率低于20%;当pH值为11.0时,黄铜矿无捕收剂浮选的矿浆电位区间为0.35~0.85 V。当pH值为10.0、丁黄药浓度为5×10-5 mol/L时,方铅矿浮选的矿浆电位为0.45~0.55 V,而黄铜矿在0.45~0.80 V的电位区间具有良好的浮选性能;对闪锌矿而言,当pH值为9.0时,矿浆电位在-0.40~0.80 V区间都不具有良好的可浮性。在浮选体系中,黄铜矿表面氧化会产生元素S0,当矿浆电位从-0.2V增大至0.6 V,黄铜矿表面氧化产生的元素S的数量逐渐增大,黄铜矿的无捕收剂浮选性能越来越好。从南京和青海2个铅锌矿山的应用情况来看,采用电位调控浮选技术可以大幅度缩短铅矿石的浮选时间,减少浮选机数量。例如在南京某铅锌矿,由于采用电位调控浮选技术,原来2个系列每天处理900 t矿石,现在采用一个系列即可处理。