【作者】 皮关华；

【导师】 徐徽；

【作者基本信息】 中南大学 ， 冶金物理化学， 2007， 硕士

【摘要】 镍钼矿在我国湖南省和贵州省有着丰富的储量，有着巨大的经济价值。由于它是一种难选矿，采用传统的物理选矿技术，较难将有用组分进一步富集。传统的火法冶金技术也达不到将钼、镍等众多金属组分分离的目的，中外也无适用的现成生产技术。针对这一现状，通过对各种方案的比较，本论文研究了一种利用镍钼矿制备钼酸铵的新工艺。该工艺主要包括焙烧、浸出、溶剂萃取三个过程。即用氧化焙烧法先氧化镍钼矿，将镍钼矿中的镍钼等金属硫化物转化为氧化物，同时将反应生成的SO₂气体通入到饱和碳酸钠溶液中，用来制备焦亚硫酸钠，可消除SO₂对环境的污染；接着在通入活氧的条件下，用强碱（NaOH）选择性浸出提取钼，则可以达到将钼镍分离的目的；然后通过加入MgCl₂来净化除杂，用溶剂萃取法来提纯浸出液中的钼，最终制备出钼酸铵的崭新工艺流程。在焙烧过程中，镍钼矿中镍的硫化物变成了镍的氧化物，从而有利于进一步酸浸提镍。另外该反应在常压下进行，对设备要求低，成本也比较低，并且适应性强，污染少。通过单因素实验，研究了焙烧温度和焙烧时间等因素对镍钼矿焙烧脱硫的影响。实验结果表明，焙烧的最佳工艺参数为：镍钼矿（-120目），焙烧温度600℃，焙烧时间2h。考察了焙烧情况、浸出温度、反应时间、加碱量等因素对镍钼矿浸出率的影响。实验结果表明，浸出的最佳工艺参数为：NaOH（占理论用量的1.2倍）作浸出剂，浸出温度为90℃，通活氧2h，液固比为3∶1。通过活氧碱浸出过程动力学研究，发现钼的浸出过程受化学反应模型控制，浸出过程的速度随反应速度常数的增大而增大，因此提高浸出温度是提高钼浸出率的一个主要强化手段。对相比、萃取时间、pH值、反应温度等因素对除杂后母液的萃取工艺的影响进行了研究。实验结果表明，萃取的最佳工艺参数为：相比（O／A）为1∶1，萃取时间3min，母液pH值2.0～3.5，反应温度为常温。研究了相比、氨水浓度、反萃时间等对富钼有机相的反萃工艺的影响。实验结果表明，反萃最佳工艺参数为：相比1∶1，氨水浓度12.5％，反萃时间10min，静置时间30min。在最佳工艺条件下，焙烧脱硫率为90.1％左右，钼的损失仅为1.86％左右，浸出率可达到99.50％左右，主要杂质磷、砷、硅等的去除率均在99％以上，除钒率为98.7％，萃取率为98.4％，反萃率可达到97.2％。应用等离子光谱（ICP-AES）测定了浸出母液和除杂液的化学成分。应用X-射线衍射（XRD）和等离子光谱（ICP-AES）对制备出来的钼酸铵进行了物相分析和化学成分分析，分析结果表明，按此工艺路线生产的钼酸铵，为含少量硫酸铵、氯化铵和偏钒酸铵的粗钼酸铵，钼酸铵样品的纯度为：95.32％，偏钒酸铵的含量为0.65％，本次实验制得的产品还含少量硫酸铵、氯化铵等杂质。钒的问题可以通过购买中南大学肖连生教授的专利来处理（专利号：200510136644.4，公开号：CN1792819），硫酸铵、氯化铵等杂质可以在钼酸铵的精制过程中去除。更多还原

【Abstract】 The Ni-Mo mineral has a abundant storage capacity in the provinceof Hunan and Guizhou in our country and it has a huge economic value.Because it is a kind of refractory mineral, adopting the traditionalphysical technique for ore-dressing is difficult to enrich the valueelements from the ores.The traditional pyro-metallurgy could not yetachieve the purpose of separation molybdenum, nickel from othermetals.There was no proper productive process to treat with it both inChina and other countries.On this condition, through the comparison towarding various project,a new productive process of ammonium molybdate from Ni-Mo ore hadbeen studied in this thesis.The process mainly consisted of roasting, leaching, and solventextraction three parts. At first, oxygenize the Ni-Mo ore by using themethod of oxidizing roast to make the Ni、Mo and other metals sulphideconversing oxidate. At the same time, using the saturated Na₂CO₃ toimbibite the air of SO₂ which released during the process of response tomake sodium pyrosulfite, it can erase the pollution of SO₂ toenvironments. Nextly, using NaOH to leach molybdenum selectively atthe condition of inleting O₃, so that it can achieve the purpose ofseparating the molybdenum and nickel. Thirdly, MgCl₂ solution isapplied to remove the impurities and solvent extraction technology hasbeen accepted to refine molybdenum to prepare Ammonium molybdate.During process of roast, the nickel sulphide of the mineral of Ni-Mohas inverted into the nickel oxide, it has advantageous to furthersour-leach to extract nickel. Moreover, the reaction can carry on in theway of normal atmosphere, hasing a low request to the equipments, lowcost, intensive adaptability, less pollution.This thesis researchs the influence of roast temperature and roasttime to the desulphur roasting of Ni-Mo ores through a single factorexperiment. Results show that the best craft parameters are: the Ni-Mominerals （powder was-120 mush）, roast temperature 600℃, roast time is 2h.The effect for the extraction ratio of Ni-Mo minerals of roastingstate, leaching temperature, leaching times, odium hydroxide quantity isinvestigated.The experimental results show that the optimal technologicalparameters of leach are: NaOH （1.2 times）, leaching temperature was90℃, adding active-oxygen time 2 hours, the ratio of liquor to solid was3:1.Through the research of dynamics by process of the active-oxygenalkali leaching, discover the process of Mo-leaching being controlled bythe chemical reaction model, the leach speed is added with the thereaction speed constant, so it is a major enhance means to raise the leachrate of molybdate by raising leach temperature.The effect for the extraction technique of the volume ratio of organicphase to aqueou, extraction time, pH value, reaction temperature, etc areinvestigated. The experimental result show that the optimal technologicalparameters of extraction process: the volume ratio of organic phase toaqueous （O/A） is 1:1, extraction time is 3 minutes, pregnant solution pHvalue is 2.0～3.5, reaction temperature is normal temperature.The effect for the extraction technique of the volume ratio of organicphase to aqueous, Ammonia concentration, anti-extraction time, etc, onthe anti-extraction process for Mo-contain organic phase solution isinvestigated.The experimental results show that the optimal technologicalparameters of anti-extraction process is: the volume ratio of organic phaseto aqueous is 1:1, ammonia concentration is 12.5%, anti-extraction timeis 10 minutes, place time is 30 minutes.Under the optimal technological parameters, desulphurizing roastingratio is about 90.1%, the loss ratio of Mo is 1.86%, leaching ratio couldreach 99.50%; disposal ratio of impurities P and As are both over 99%,while V is 98.7%, extraction ratio could reach 98.4%, and anti-extractionratio could reach 97.2%.Plasma spectrum （ICP-AES） is instituted to determine the chemicalcomponent of leaching solution and solution which has removedimpurities. X-diffraction（XRD） and the ICP-AES are instituted to analyzethe phase and chemical component of the ammonium molybdate, the results of ranalyze show that the ammonium molybdate specimen whichprepared by this process with a little amount ammonium sulfate,ammonium chloride and ammonium metavanadate are coarse ammoniummolybdate, the purityof ammonium molybdate is 95.32%, the contentammonium metavanadate is 0.65%, also contenting some impurities likeammonium sulfate, ammonium chloride. It is a good way to buy thepatent of Xiao Liansheng coming from CSU to removal the problem of V（patent number: 200510136644.4, public nubmer. CN1792819）. It canremoval the ammonium sulfate, ammonium chloride during the refineprocess of ammonium molybdate.更多还原