不同金属硫化物从钨酸盐溶液中除钼的效果

针对钨冶炼过程中钨钼分离这一关键问题,研究了利用CuS,CoS,NiS,PbS,FeS,ZnS和HgS等金属硫化物从钨酸盐溶液中除钼的效果.对含钼的Na2WO4或(NH4)2WO4溶液用Na2S或(NH4)2S 进行硫化处理,使其中的MoO2-4转化为MoS2-4,然后加入上述金属硫化物进行除钼.结果表明,CuS,CoS和NiS在Na2WO4或(NH4)2WO4溶液中均具有良好的除钼效果,综合考虑经济、环保等因素,认为CuS是最经济合理的钨钼分离新试剂.考察了试剂用量、反应温度和溶液pH值对除钼效果的影响,并获得了最佳除钼工艺条件,即在CuS试剂用量为理论量的3～4倍、室温下搅拌反应1h的条件下,可使溶液中的Mo从0.6～0.77g/L降至0.007～0.02g/L,除钼率达96.0%～98.5%,整个除钼过程中钨的回收率达99.75%以上.     

甲基碳酸酯季铵盐的合成、转型及萃取性能

针对现有季铵盐N263合成工艺毒性大、转型步骤冗长和设备要求高等问题,以三辛基甲基溴化铵为催化剂、碳酸二甲酯(DMC)为季铵化试剂替代传统的氯甲烷与N235在高压反应釜中合成甲基碳酸酯季铵盐,考察反应物摩尔比、反应温度、溶剂、催化剂和反应时间等主要因素对叔胺转化率的影响。结果表明:在最适宜的条件下,当N235与碳酸二甲酯的摩尔比为1:5.6、甲醇与N235的体积比为1:2、三辛基甲基溴化铵催化剂为反应体系总质量的5%、反应温度为110℃、反应时间为8 h时,叔胺转化率可达99.39%;该甲基碳酸酯季铵盐用3 mol/L H2SO4酸洗、0.6 mol/L NaOH碱洗,转型为SO2-4季铵盐;用转型后的2?4SO季铵盐按以下比例配成有机相:50%转型后的SO2-4季铵盐+30%仲辛醇+20%磺化煤油(体积分数),在25℃下用该有机相萃取钨矿苏打浸出模拟料液(105.7 g/L WO3,100 g/L Na2CO3),相比O/A=2:1,萃取时间为5 min时,单级萃钨率可达80.88%,有机相饱和萃钨量(以WO3计)为83.92 g/L。     

钨酸盐溶液中除钼砷锑锡等杂质的研究

应用合成的改进型试剂M115 a,研究了从钨酸盐溶液中选择性沉淀除钼、砷、锡、锑等杂质的新工艺。小型试验证明其除杂效果比用M115有大幅度提高 ,在温度为 2 0～ 6 0℃ ,沉淀剂M115 a的用量为理论量的 3～ 4倍以及保温时间为 1h时 ,对含WO3 为 2 10 g/L ,Mo为 0 .6 g/L ,As,Sb ,Sn各为 0 .2g/L的 (NH4 ) 2 WO4 溶液 ,最终的纯溶液中Mo和WO3 的浓度比小于 0 .5× 10 -4 ,同时溶液中的砷、锡、锑也大部分被除去 ,WO3 回收率大于99.9%。在结晶率为 90 %左右时 ,所得APT中上述杂质的含量全部符合GB10 116 88 APTO级标准。     

选择性沉淀法从钨酸盐溶液中除钼的工业试验

对“选择性沉淀法从钨酸盐溶液中除钼”新工艺进行了工业试验。结果表明对处理含WO3130～244g/L,含钼0.535～2.55g/L的工业钨酸铵溶液,除钼后净液中Mo/WO3达到2.00×10     

高位阻β-二酮和LIX84混合萃取剂从氨性溶液中萃取铜

以Cu2+-NH3-Cl--H2O氨性溶液为被萃水相,研究高位阻β-二酮和LIX 84混合萃取剂对铜的萃取.考察混合萃取剂β-二酮和LIX 84总浓度及相对含量、被萃水相pH值及总氨浓度和相比等因素对铜萃取的影响.结果表明,最优萃取条件如下:β-二酮与LIX 84的体积比为1:1,萃取剂浓度为20%,水相铜离子浓度为3 g/L,总氨浓度为3mol/L(氨与氯化铵的摩尔比为1:2),初始pH值为8.95,相比(O/A)为1:1,反萃剂(硫酸)浓度为90g/L.在此最优条件下,铜萃取率接近100%,共萃氨量为36.1 mg/L,反萃率达97%.     

氧化锆陶瓷中温化学镀镍三元络合剂的研究

目的优化中温化学镀镍三元络合剂体系,得到性能优良的化学镀镍层。方法选取乳酸、冰乙酸及柠檬酸作为络合剂组分,以镀速和含磷量为考察指标,通过设计L9(34)正交实验,研究次亚磷酸钠、乳酸、冰乙酸及柠檬酸的浓度对化学镀镀速以及镀层磷含量的影响。结果综合考虑镀速和磷含量,得到的最佳三元络合剂体系为20 mL/L乳酸+15 mL/L冰乙酸+10 g/L柠檬酸,该条件下镀速为6.4 mg/h,镀层磷质量分数为8.8%。结论采用优化的络合剂体系,可以获得致密均匀、结合力良好的化学镀镍层。     

化学镀Ni-W-P薄膜的制备及其耐蚀性能的研究

目的 制备Ni-W-P合金薄膜并研究其耐蚀性.方法 在碱性镀液(pH=11)中,以次亚磷酸钠为还原剂,柠檬酸钠为络合剂,以铜锌合金为基材,采用化学镀制备Ni-W-P薄膜.通过X射线荧光仪、SEM、电化学极化曲线等方法 ,研究还原剂次亚磷酸钠浓度、络合剂柠檬酸钠浓度以及反应时间对薄膜厚度、表面形貌和耐蚀性的影响.结果 固定其他参数不变的条件下,在还原剂浓度为0.2 mol/L及络合剂浓度为0.26 mol/L时薄膜厚度最大,分别为0.2975、0.1978μm.随着次亚磷酸钠浓度的增大,Ni-W-P薄膜表面致密度增加,孔隙率减少.当次亚磷酸钠的浓度为0.1 mol/L时,薄膜表面的颗粒较细小,孔隙较多;当次亚磷酸钠的浓度为0.4 mol/L时,薄膜表面的孔隙明显减少,表面更加均匀且致密度变好;络合剂和还原剂的改变对薄膜腐蚀电位没有明显影响,腐蚀电流密度在还原剂浓度为0.4 mol/L、络合剂浓度为0.28 mol/L时达到最小,分别为2.38×10-6、2.23×10-6 A/cm2;随着络合剂和还原剂浓度的增大,薄膜表面趋于致密;随着反应时间的增加,膜层厚度明显增大,腐蚀电流密度随着时间的增加而减小,化学镀4 h薄膜腐蚀电流密度最小,为1.679×10-6 A/cm2.Ni-W-P薄膜厚度可达到4.14μm.结论 还原剂浓度为0.4 mol/L,络合剂浓度为0.28 mol/L时,薄膜的耐蚀性最好,反应时间的延长有利于薄膜耐蚀性能的优化.     

亚硫酸钠-柠檬酸钾体系络合剂对镀金层性能的影响

目的 研究亚硫酸钠-柠檬酸钾体系络合剂对可伐基板镀金层共晶焊接性能的影响机理,从而优化络合剂含量工艺范围,提升镀金层金锗共晶可焊性。方法 采用扫描电子显微镜及能谱仪（SEM-EDS）、X射线衍射仪（XRD）、极化曲线等分析方法,结合镀金层孔隙、金锗共晶焊接润湿性和剪切强度测试,研究了亚硫酸钠-柠檬酸钾体系络合剂,对镀金层表面金锗焊料润湿性,金锗共晶层结合力、表面和截面形貌、结晶状态、孔隙,以及金锗共晶焊接界面微观形貌等的影响。结果 亚硫酸钠和柠檬酸钾均能起到络合剂作用,当络合剂亚硫酸钠质量浓度为120～160 g/L和柠檬酸钾质量浓度为40～60 g/L时,络合剂含量的增加可使镀金液阴极过电位明显增大,从而使所制备的镀金层结晶更加致密。当络合剂亚硫酸钠质量浓度为160～200 g/L、柠檬酸钾质量浓度为60～100g/L时,电沉积的镀金层表面明显平整,截面形貌致密,孔隙少,且以（311）晶面择优生长,晶粒尺寸为43.7nm,晶面间距为0.123nm,金锗焊料润湿良好,金锗共晶层结合力较大,剪切强度可达3 MPa以上,可满足金锗共晶焊接使用要求。结论 亚硫酸钠-柠檬酸钾体系络合剂含量对镀...     

3D打印大流量微反应器在萃取分离铂钯铑中的小型化应用

进行了3D打印多通道微用于TBP萃取分离盐酸体系中的铂钯铑离子的研究。结果表明，在处理量为11.5 L/h，油/水相比为1:1，流速为192.5 mL/min的条件下铂萃取率为84.26%，钯萃取率为96%，分离系数βPd/Rh、βPt/Rh分别为753.5、132.35；使用结构优化后的反应器对铂和钯萃取率分别提高2%和1%。3D反应器利用锯齿型微通道具有微漩涡的微效应，通过叠加锯齿型微通道数量从而实现处理量的放大。萃取效果优于常规工业单级萃取过程，尤其是在提高分离系数、缩短萃取时间效果尤佳，且单台微萃取系统的处理量就已经接近了工业生产级。     

高位阻β-二酮从氨性蚀刻废液中萃取铜

采用高位阻β-二酮（1-（4’十二烷基）苯基-3-叔丁基-1,3-丙二酮）作为萃取剂从模拟印刷电路板（PCBs）蚀刻废液中萃取铜。利用离子强度与萃取反应平衡常数的关系校正模拟的萃取等温线,该模拟萃取等温线与实验测得萃取等温线基本相符。通过实验确定萃取剂浓度、相比、萃取级数和反萃级数等萃取工艺参数。结果表明,在室温下对于铜离子浓度为112g/L、总氨浓度为7mol/L的模拟氨性蚀刻废液的最佳萃取条件为：萃取剂浓度为40%,相比为5：4,萃取时间为5min。在此条件下,经过一级萃取,蚀刻废液中铜离子浓度可降低至63.24g/L,能返回到电路板的生产中循环使用。用含铜30g/L,硫酸浓度180g/L的模拟废电解液对负载有机相进行反萃,相比（O/A）为1：2,经一级反萃,铜的反萃率可达98.27%。     

利用D309树脂离子交换分离宏量钨和钼

基于钨、钼在水溶液中聚合能力的差异,提出一种利用D309树脂离子交换分离钨、钼的新方法。静态实验表明,分离钨、钼的最佳pH值为7.0,最佳接触时间为4 h,钨、钼分离系数达到9.29。等温吸附过程研究表明,D309树脂对钨、钼的吸附分别属于Langmuir模型和Freundlich模型。吸附动力学研究表明,D309树脂对钨的吸附属于内扩散控制。对于含70 g/L WO3和28.97 g/L Mo的料液,经动态吸附分离钨、钼后,所得流出液中Mo与WO3的质量比达76,所得解吸液中WO3与Mo的质量比达53.33。     

萃取法分离钨钼研究进展

钨钼分离是钨冶金中的一个技术性难题,长期以来,国内外学者围绕钨钼分离进行了大量研究,采用的方法有很多,如萃取法、沉淀法、离子交换法等。溶剂萃取法是一种深度分离钨钼的有效方法,也是钨钼分离研究中的一个非常活跃的领域。当前萃取法分离钨钼仍处在研究阶段,离工业化仍有距离,本文对几十年来萃取法分离钨钼的研究进展进行了简单的回顾和评述,对比和分析各种萃取分离方法特点,指出加强研究钨钼化合物物理化学性质差异、钨钼氧化还原体系配合物性质差异、新型高效萃取剂与新型萃取体系以达到钨钼的深度分离,是值得研究的方向。     

Removal of vanadium from ammonium molybdate solution by ion exchange

The separation techniques of vanadium and molybdenum were summarized, and a new method of removal V(Ⅴ) from Mo(Ⅵ) by adsorption with chelate resin was presented. Nine kinds of chelate resins were used to investigate the adsorbent capability of V(Ⅴ) in ammonium molybdate solution with static method. The test results show that DDAS, CUW and CW-2 resins can easily adsorb V(Ⅴ) in ammonium molybdate solution, but hardly adsorb Mo(Ⅵ). The dynamic experimental results show more than 99.5% of V(Ⅴ) can be adsorbed, and the adsorption rate of Mo(Ⅵ) is less than 0.27% at 294-296 K for 60 min at pH 7.42-8.02. The mass ratio of V to Mo decreases to l/5 0000 in the effluent from 1/255 in the initial solution. The loaded resin can be desorbed by 5% NH3·H2O solution, and the vanadium desorption rate can reach 99.6%. The max concentration of vanadium in desorbed solution can reach 20 g/L, while the concentration of molybdenum is less than 0.8 g/L.     

Mathematical model and reaction mechanism of molybdenum and tungsten extraction with TRPO from peroxide solution

To understand the behavior of molybdenum and tungsten extracted by tri-alkyl phosphine oxide (TRPO) from peroxide solution, the extraction mechanism was studied by slope method and Raman and FTIR spectroscopy. The empirical formulas of molybdenum and tungsten extraction distribution ratio (D_Mo and D_W) as functions of equilibrium pH, TRPO concentration and temperature were obtained by establishing mathematical models. Furthermore, the reliability of the empirical formula was verified in the H⁺?W?Mo?H₂O₂ solution. The results indicate that the calculated values of D_Mo or D_W were consistent with the experimental values. The apparent extraction equilibrium constants of molybdenum and tungsten were =8.51×10³ (0.74≤pH_e≤1.7), =99.89×10³ (1.7<pH_e≤4.62) and =2.65×10³ (0.92<pH_e<2.16) at 20 °C, respectively. The main extraction complex of molybdenum or tungsten was [H₂(Mo or W)₂O₃(O₂)₄(H₂O)₂]·2TRPO. These empirical formulas can be used to analyze and estimate the extraction and separation of Mo and W from low molybdenum and tungsten concentration solutions.     

A study on separation of molybdenum from tungsten by an adsorption process using activated carbon

In this paper a new process for separation of molybdenum from tungsten is described. When sodium tungstate solution containing molybdenum is treated with alkali sulfide in the proper condition, the molybdenum is transformed into the thiomolybdate and the tungsten is present as tungstate. When the solution is brought into contact with activated carbon, the molybdenum contained in the solution can be adsorbed quantitatively and the tungsten remaining in the raffinate can be recovered. The new process has advantages such as good results in removing molybdenum, little loss of tungsten and easy operation.     

用季铵盐从模拟钨矿苏打浸出液中直接萃取钨

针对从钨矿碱性浸出液中直接萃取钨制取仲钨酸铵(APT)工艺萃取分相慢、反萃液中WO3浓度偏低的问题,采用季铵盐三辛基甲基氯化铵(Tri-n-octylmethyl-ammonium chloride,TOMAC)为萃取剂,对从钨矿苏打浸出模拟料液中直接萃取钨进行研究,分别考察钨矿浸出液中Na2CO3浓度、反萃剂组成及浓...     

Eliminating Molybdenum from Sodium Tungstate Solution by Selective Precipitation

Eliminating Molybdenum from Sodium Tungstate Solution by Selective Precipitation     

Precursor solution prepared by evaporation deamination complex method for solvent separation of Mo and W by H2O2-complexation

An novel method on preparation of precursor solution for solvent separation of molybdenum (Mo) and tungsten (W) by hydrogen peroxide (H₂O₂)-complexation from the ammonium tungstate solution containing high Mo was studied. The precursor solution was obtained via evaporation deamination and H₂O₂-complex transformation processes. Then it was extracted with a mixture extractant of tri-alkyl phosphine oxide (TRPO) and tributyl phosphate (TBP) to separate Mo and W. The results indicated that the evaporation deamination complex method reduced the acid consumption by more than 90% in comparison with the traditional directly acid regulation complex method. The transformation rates of W and Mo were higher than 95% and the decomposition rate of H₂O₂ was less than 15% at a 1.8-1.9 times H₂O₂ dosage, 45-50 °C, initial pH of 1.80-1.90, and transformation volume ratio of 100% for 60 min in the H₂O₂-complexation transformation process. The minimum extraction rate of W was 2%, the maximum extraction rate of Mo was 82.6% and the highest separation coefficient was 76.7 in a single-stage extraction.     

Direct extraction of Mo(VI) from acidic leach solution of molybdenite ore by ion exchange resin: Batch and column adsorption studies

The adsorption behavior of ion exchange resin D301 in the extraction of hexavalent molybdenum from high acidic leach solution was investigated. SEM, EDS and Raman spectra analyses were applied to studying the adsorption capacity, reaction kinetics and possible adsorption mechanism in detail. Results showed that the adsorption capacity of D301 resin for molybdenum from high acidic leach solution was up to 463.63 mg/g. Results of the kinetic analysis indicated that the adsorption process was controlled by the particle diffusion with the activation energy 25.47 kJ/mol (0.9α1.2 mm) and 20.38 kJ/mol (0.6α0.9 mm). Furthermore, the molybdenum loaded on the resin could be eluted by using 2 mol/L ammonia hydroxide solution. Besides, dynamic continuous column experiments verified direct extraction of molybdenum from acidic leach solutions by ion exchange resin D301 and the upstream flow improved dynamic continuous absorption.