硫酸铵焙烧红土镍矿的溶出液制备黄铵铁矾

为得到硫酸镍溶液除铁的合适工艺条件,以硫酸铵焙烧红土镍矿的熟料溶出液为原料,采用 NH4HCO3合成黄铵铁矾。考查了反应温度、反应时间、反应终点pH以及Fe3＋初始浓度对除铁率的影响。以上因素均对Fe3＋的去除率有显著影响,其中反应温度的影响最为显著。合适的反应条件为：Fe3＋初始浓度19.36 g/L、反应温度95℃、反应时间3.5 h、反应终点pH2.5。在此条件下所得到的黄铵铁矾为包含片状或棱形颗粒的花簇结构。     

锈蚀法提取预还原红土镍矿中镍和钴

以国外某红土镍矿经氯化离析法预处理后的还原矿为原料,对锈蚀法处理预还原红土镍矿工艺进行研究,系统考察酸料质量比、空气流量、锈蚀温度、锈蚀时间、搅拌速率以及固液比(固体质量与液体体积比,mg/mL)对铁、镍和钴浸出率的影响。结果表明:在酸料质量比0.10,空气流量1 L/min、锈蚀温度80℃、锈蚀时间8 h、搅拌速率300 r/min和固液比1:10的条件下,镍和钴的浸出率分别达到90.9%和80.2%,铁的浸出率仅为9.9%,实现了铁与镍和钴的分离。     

镍红土矿高压酸浸过程的金属元素浸出行为

以镍、钴的提取为目的,研究褐铁矿型镍红土矿高压酸浸过程中各金属元素的浸出行为,探讨硫酸加入量、浸出温度、浸出时间及液固比对各金属元素浸出率的影响.实验结果表明,在优化条件下Ni、Co、Mn和Mg的浸出率分别达到97%、96%、93%和95%以上,则Fe的浸出率小于1%.对高压浸出渣的分析表明,渣中的铁和硫主要分别以赤铁...     

离子交换吸附富集红土镍矿浸出液中的镍

研究高镁铁质红土镍矿硫酸浸出液中镍的高效提取方法。通过在d 150 mm×1800 mm PVC柱中填充12 L CN27离子交换树脂,对高镁铁质红土镍矿硫酸浸出液进行动态吸附。研究初始液pH、Ni2+和Fe2+的质量浓度、流速、吸附时间等参数对树脂有效吸附量和吸附效率的影响。结果表明:初始液中Ni2+质量浓度2.5 g/L、pH 3~5、流速1.0 L/min、树脂饱和吸附时的有效利用率达85%~93%,树脂吸附Ni2+的最高有效吸附量可达58.0 g/kg;初始液中Ni2+质量浓度2.5 g/L、pH 4.5、流速1.0 L/min时,吸附后液Ni2+质量浓度1.0 mg/L时,树脂吸附Ni2+的有效吸附量可达41.8~42.0 g/kg,富集液中Ni2+的富集倍数达到25以上,镍离子的质量浓度提高到54 g/L以上;初始液中Fe2+的质量浓度增加,树脂对镍的吸附量降低,不仅会导致富集液中Ni2+的质量浓度降低,富集液中Fe2+的质量浓度也会增加。离子交换吸附不但能使低浓度含镍溶液富集到满足镍电积工艺的要求,且能对杂质进行有效分离。     

红土镍矿在NaOH亚熔盐体系中的预脱硅

研究常压下高浓度氢氧化钠浸取红土镍矿的预脱硅过程,考察搅拌强度、液固比、氢氧化钠浓度、反应温度和原矿粒径对红土镍矿中硅的反应率的影响.结果表明:二氧化硅的反应率受克-金-布产物层固膜扩散控制, 并由阿累尼乌斯方程得到反应的表观活化能为53.74 kJ/mol.结合动力学实验结果和电子扫描电镜(SEM)及X射线能谱(EDAX)分析,证明在反应过程中通过固相产物层的内扩散为反应过程的控制步骤.     

国内外红土镍矿处理技术及进展

综述了国内外红土镍矿的处理现状.指出红土镍矿的开发要综合考虑矿石镍、钴含量和矿石类型的差异,以及当地燃料、水、电和化学试剂等的供应状况.现阶段回转窑干燥预还原-电炉还原熔炼工艺在红土镍矿的开发中仍占主导地位,加压酸浸法随着大型压力釜制造技术的成熟也越来越受到重视和应用.我国在红土镍矿的工程化方面很欠缺,元江贫红土镍矿的开发必须综合考虑镁的产品结构和经济利用,元石山镍矿的开发必须考虑铁的综合利用.     

低污染沉矾除铁试剂的选择和影响

正本文阐述了热酸浸出——低污染沉矾除铁沉矾试剂的选择,分析了实际生产中使用沉矾试剂碳酸氢铵的影响及解决办法。低污染沉矾除铁工艺原理湿法炼锌热酸浸出溶液经过稀释或者中和,在p H为1.0~2.0、温度为90℃以上的条件下,三价铁离子可以与一价阳离子、硫酸根离子反应,生成易于沉淀过滤的黄铁矾,同时产生酸,主要化学反应式如下:A2SO4+3Fe2(SO4)3+12H2O=2AFe3(SO4)2(OH)6↓+6H2SO4(1)随着反应的进行,溶液中的酸会越     

相转变过程对红土镍矿氯化离析的影响

在氯化剂CaCl2·2H2O的加入量为原矿质量的8％（以氯计）、还原剂焦炭加入量为原矿质量的6％及升温速率为5℃/min的条件下,对菲律宾红土镍矿进行氯化离析;采用TG-DTA和XRD研究菲律宾红土镍矿氯化离析升温至1 000℃及冷却过程中的物相转变.结果表明:红土镍矿中的氧化亚铁在700℃开始进入蛇纹石中,形成富铁橄榄石相,破坏蛇纹石的晶格结构,提高镍的活性,有利于镍的氯化和离析;而氯化剂所释放的氯成为铁迁移的媒介;冷却过程中物相没有发生明显变化.当生料中Fe3O4的加入量为原矿的10％（质量分数）时,精矿中镍的品位达到13.14％,回收率达到80.12％,比未加Fe3O4时的回收率提高了约10％.     

Transformation and leaching kinetics of silicon from low-grade nickel laterite ore by pre-roasting and alkaline leaching process

The mineralogical phase transformation of a low-grade nickel laterite ore during pre-roasting process and the extraction of silicon during alkaline leaching process were investigated. The results indicate that the reaction activity of nickel ores is effectively improved by pre-roasting at 650 °C for 2 h, because of the transformation of lizardite into magnesium olivine and protoenstatite. When finely ground ore samples (44–61 μm) pre-roasted firstly react with sodium hydroxide solution (60 g/L) with a solid/liquid ratio of 1:5 at 140 °C for 120 min, the extraction of silicon can reach 89.89%, and the other valuable elements of magnesium, iron and nickel are accumulated in the solid residues. The leaching kinetics of nickel laterite ore can be described successfully by the diffusion through the product layer control model. The activation energy is calculated to be 11.63 kJ/mol and the kinetics equation can be expressed as 1–3(1–x)^2/3+2(1–x)=13.53×10^?2exp[–11.63/(RT)]t.     

Microwave assisted atmospheric acid leaching of nickel from laterite ore

The recovery of nickel from laterite ore with sulphuric acid under the effect of microwave irradiation was studied.The experimental results indicated that the extraction rate of nickel was influenced by reaction time,sulphuric acid concentration,and temperature,especially by microwave power.The results obtained from the experiments of orthogonal arrays showed that the optimum conditions of sulphuric acid concentration,reaction time,microwave power,and temperature were 25 vol.%,1.5 h,600 W,and 90°C,respectively.Under the optimal conditions,the nickel recovery could reach approximately 90.8%,which was higher than that obtained by conventional water bath heating.Kinetic experiments showed that the leaching of nickel in a sulphuric acid medium was controlled by chemical reaction occurring on the surface of laterite ore.The apparent activation energy was 38.9 kJ/mol.Microwave heating technology is efficient,clean,and easy to control and facilitate continuous processing of materials.     

某印尼低品位红土镍矿的微观结构及晶体化学(英文)

为深入研究红土镍矿的镍富集原理,利用电子显微镜、扫描电镜、X射线衍射分析以及电子探针微区分析对含镍0.97%的某印尼低品位红土镍矿的工艺矿物学进行研究,以了解镍钴有价金属的分布及赋存状态。实验表明:该矿样主要矿物为针铁矿(含量约为80%),镍含量约为0.87%;含镍、铁、镁的结晶水硅酸盐矿物((Mg,Fe,Ni)2SiO4)的含量约为15%,如利蛇纹石((Fe,Ni,Al)O(OH))和橄榄石((Mg,Fe,Ni)3Si2O5(OH))等,镍含量约在1.19%左右;其它含量较低的物相为赤铁矿、磁赤铁矿、铬铁矿和石英等,这些矿物的镍含量极低。钴土矿是含钴矿物,分析发现该矿物往往有较高的镍和钴含量。微观检测发现:红土镍矿微观结构复杂,不同矿物之间共生普遍,主要矿物的微观结构松散,因而传统选矿方式很难实现镍的富集。     

Desiliconization kinetics of nickeliferous laterite ores in molten sodium hydroxide system

A novel process was proposed for treating nickeliferous laterite ores with molten sodium hydroxide.The effect on silicon extraction caused by the factors,such as stirring speed,reaction temperature,particle size and NaOH-to-ore mass ratio,was investigated.The results show that increasing stirring speed,reaction temperature and NaOH-to-ore mass ratio while decreasing particle size increases silicon extraction rate.The desiliconization kinetics of nickeliferous laterite ores in molten sodium hydroxide system ...     

红土镍矿深度还原-磁选工艺富集镍和铁（英文）

提出采用"深度还原-磁选"工艺从红土镍矿中富集镍和铁。结果表明,在还原温度1275℃、还原时间50 min、渣相碱度1.0、配碳系数2.5和磁场强度72 kA/m的条件下,可得到镍品位为6.96%、回收率为94.06%和铁品位为34.74%、回收率为80.44%的镍铁精矿产品。分析表明,还原温度和时间影响深度还原发生的可能性及反应进度,渣相碱度影响炉料中渣的组成及镍铁元素从基体中溢出富集形成镍铁颗粒的速度,深度还原反应过程中镍铁颗粒生成、聚集并逐渐长大,经磁选后可有效促进镍铁矿物与脉石矿物分离。