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 k J/mol（0.9-1.2 mm） and 20.38 k J/mol（0.6-0.9 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.

Agglomeration and leaching behaviors of copper oxides with different chemical binders

The chemical binder is one of the critical factors affecting ore agglomeration behavior and leaching efficiency.In this study,we in-vestigated the effect of the type of binder and mass fraction of the H_(2)SO_(4)solution used on the curing,soaking,and leaching behavior of ag-glomerations.The results revealed that Portland cement(3CaO·SiO_(2),2CaO·SiO_(2),and 3CaO·Al_(2)O_(3))was the optimal binder for obtaining a well-shaped,stable agglomeration structure.A higher extraction rate was achieved when using Portland cement than that obtained using sodi-um silicate,gypsum,or acid-proof cement.An excessive geometric mean size is not conducive to obtaining well-shaped agglomerations and desirable porosity.Using computed tomography(CT)and MATLAB,the porosity of two-dimensional CT images in sample concentrations L1-L3 was observed to increase at least 4.5vol%after acid leaching.Ore agglomerations began to be heavily destroyed and even to disinteg-rate when the sulfuric acid solution concentration was higher than 30 g/L,which was caused by the excessive accumulation of reaction products and residuals.

铁尾矿酸浸液制备聚氯化铁的试验研究

为探索某选矿厂铁尾矿回收利用的新途径,对铁尾矿酸浸液制备聚氯化铁的试验过程进行了研究,并将自制的聚氯化铁应用到高岭土悬浊液的混凝试验中测试产品的絮凝性能。结果表明:聚合的适宜条件为温度为40℃、pH为1.0、聚合时间为3h,在该条件下合成的聚氯化铁盐基度为20.91%,符合相关标准,影响聚合过程因素的主次顺序依次为聚合温度、pH、聚合时间;混凝的适宜条件为聚氯化铁投加量为250 mg/L、pH为7.0、搅拌时间为3min、温度为20℃、混凝时间为60min,在该条件下浊度去除率为95.54%,产品除浊效果良好。

水杨酸螯合树脂对铀的吸附性能

利用低温氮气吸附—脱附法测定水杨酸螯合树脂的比表面积、孔径;考察了水杨酸螯合树脂的热力学稳定性;研究了溶液pH、ρ(Cl^(-))对水杨酸螯合树脂铀吸附性能的影响,以及树脂的吸附等温线、吸附动力学及解吸性能。结果表明:水杨酸螯合树脂的比表面积为32.34 m^(2)/g,孔径为32.08 nm,当温度低于180℃时,水杨酸螯合树脂具有良好的热稳定性;在pH为7~9时,树脂吸附性能较好,铀吸附量达14.1 mg/g(以干树脂计,下同);Cl^(-)的存在会降低树脂对铀的吸附量,当ρ(Cl^(-))为3.0 g/L时,铀吸附量降低约9.9%;当铀溶液的平衡浓度为400 mg/L时,树脂的铀吸附量达到最大,为153 mg/g;吸附20 h,吸附过程达到平衡。酸性解吸剂与碱性解吸剂对树脂均具有良好的解吸性能,解吸率均在94%以上。在ρ(U)=21.2 mg/L、ρ(Cl^(-))=3.36 g/L的真实铀浸出液中吸附24 h,水杨酸螯合树脂的铀吸附量达14.7 mg/g,具有较好的铀吸附性能。

Leaching process of phosphorus and iron from steelmaking slag into malic acid solution

In order to remove phosphorus element from steelmaking slag and decrease iron loss,malic acid was selected as the leaching agent to dissolve steelmaking slag.Firstly,the influences of different factors,such as malic acid concentration,slag particle size,temperature,liquid/solid ratio and stirring speed,on the leaching ratios of phosphorus and iron were studied.Then,the kinetics for the leaching process of phosphorus was analyzed.The results showed that the leaching ratios of phosphorus and iron increase significantly with increasing the malic acid solution concentration and liquid/solid ratio.When the concentration of malic acid solution increases up to 0.01492 mol/L,about 80%phosphorus can be dissolved,and iron leaching ratio is less than 17%.In addition,decreasing slag particle size can obviously increase the leaching ratio of phosphorus.However,temperature and stirring speed have no significant effect on the dissolution of phosphorus and iron.The leaching kinetics of phosphorus follows the unreacted shrinking core model.Diffusion through product layer is the rate-limiting step of the leaching process,and the corresponding apparent activation energy is determined to be 3.32 kJ/mol.Finally,a semi-empirical kinetic equation was established.

离心萃取分离钒页岩酸浸液中钒铁的研究

离心萃取法是通过高速转动提高两相间的传质,并利用离心力场来实现两相快速分离的萃取方法。为提高萃取剂对钒(V)的萃取效率,强化V(IV)与Fe(II)的分离效果,本研究将离心萃取法应用于钒页岩酸浸液中钒的净化富集工艺。结果表明,在萃原液初始pH值2.0、有机相组成15 vol.%P204+85 vol.%磺化煤油、相比(O/A)1∶4、萃取时间4 min、萃取温度45℃、转速1 400 r/min的离心萃取条件下,V萃取率为87.67%。与常规萃取相比,离心萃取使V/Fe分离系数由41.78提升至127,钒的萃取饱和容量由52.63 g/L提升至70.45 g/L,表明离心萃取可有效强化钒铁分离效果,并提高钒的萃取饱和容量。

还原-中和沉淀-低酸浸出方法富集低浓度含锗浸出液中的锗

采用“还原-中和沉淀-低酸浸出”方法从低浓度含锗浸出液中高效富集锗,研究了还原中和沉淀和低酸浸出过程主要影响因素对锗分离富集的影响。结果表明,在硫化锌精矿用量为2 g/L、氧化锌烟尘用量为19 g/L、反应温度为80℃、还原时间为20 min、中和时间为240 min的条件下,锗沉淀率可达97.24%;在初始硫酸浓度为165 g/L、液固体积质量比为4 mL/g、浸出温度为60℃、浸出时间为60 min的条件下,锗浸出率可达98.78%。

Leaching behavior and microstructure of phosphorus in converter slag

Converter slag is a by-product of the steelmaking process and contains a large amount of Ca,Fe,P and other elements.If the phosphorus in the converter slag can be effectively extracted,the resulting phosphorus can be used as a phosphate fertilizer.Phosphorus in converter slag is mainly enriched in 2CaO·SiO_(2)-3CaO·P_(2)O_(5)(C_(2)S-C_(3)P)solid solution and is easily dissolved in water.Therefore,acid leaching method was used to dissolve the solid solution to extract phosphorus in converter slag,so as to realize the recycling of phosphorus resources in converter slag.The leaching behavior of three actual converter slags from different steel mills in acid leaching solutions composed of citric acid,sodium hydroxide,hydrochloric acid and deionized water was studied by X-ray diffraction,scanning electron microscopy combined with energy dispersive spectrometry,Fourier transform infrared spectroscopy and Raman spectroscopy to reveal the change in object image structure as well as SiO_(4) and PO_(4) tetrahedron before and after acid leaching.The results show that only a small amount of phosphorus in converter slag with too low basicity is enriched in C_(2)S-C_(3)P solid solution,resulting in poor leaching effect.When the converter slag has a high basicity,the removal effect of phosphorus is 70.64%-81.88%.In addition,when the basicity of converter slag is roughly the same,the dephosphorization effect of slag with high FeO content is relatively poor.And acid leaching will cause depolymerization behavior of SiO_(4) and PO_(4) tetrahedron,so that the mole fraction of Q0(Si)(asymmetric stretching vibration of Si-O bond in SiO_(4) tetrahedron with bridge oxygen number of 0)and NBO/Si(non-bridging oxygen in silicate tetrahedra)will increase.Phosphate-containing solids can be obtained from the solution after acid leaching through static precipitation,and the solids have the potential to make phosphate fertilizers.

镍渣中Ca^(2+)、Mg^(2+)在乙酸中的溶解特性研究

以电弧炉镍渣为研究对象,以乙酸为溶剂,研究了电弧炉镍渣中Ca^(2+)、Mg^(2+)的溶出特性,考察了乙酸浓度、固液比、温度、颗粒粒径对溶出过程的影响。试验结果显示:Ca^(2+)、Mg^(2+)的溶出率随着溶剂浓度、温度的升高和固液比的减小而增加。细粒径的镍渣中溶出效果更好。采用收缩核模型对溶出数据进行分析,结果显示:溶出过程受到扩散的控制,Ca^(2+)、Mg^(2+)在乙酸溶液中的溶出活化能分别为16.61 kJ/mol、21.51 kJ/mol,Ca^(2+)更易溶出。

铂钯置换后液提取碲的工艺研究

本研究以亚硫酸钠(Na_(2)SO_(3))为还原剂,探讨在铂钯置换后液还原碲(Te)的过程中,为降低后液中Te含量,提高铂钯置换后液中Te的浸出效果,对Na_(2)SO_(3)质量浓度、反应温度、Na_(2)SO_(3)反应时长、反应酸度和添加时长进行了工艺研究。结果表明,Na_(2)SO_(3)的质量浓度为100 g/L,Na_(2)SO_(3)添加时长为60 min,反应温度为60~70℃,体系中反应酸度为60 g/L、反应时长为70 min的条件最为适宜。工艺优化后,后液含碲量下降了45.2%,Te浸出率可达到最高的95.43%。

A low-cost green approach for synthesis of lead oxide from waste lead ash for use in new lead-acid batteries

This paper proposes a novel method relating to the recycling of waste lead ash originated from procedure of lead alloy production.The spent lead ash was first disposed by acetic acid leaching system,where lead ash structure wrapping impurities would be destroyed.The synthesis of lead oxide products was conducted at a lower temperature of 90℃.The effect of molar ratio of CH3 COOH to lead content of the ash on leaching efficiency was studied through the acetic acid leaching system.The results demonstrate that 84.6%of lead could be obtained in the leaching solution,while merely 0.7%of Fe blend in solution within a leaching time of 120 min.In the stage of lead oxide synthesis from leaching solution,the yield of lead oxide products could reach up to 94.4%when the molar ratio of NaOH to lead in filtrate was 2.5.This novel green method could shed light on the reuse of lead from exhausted ash with a much more convenient and environmentally friendly procedure.

钕铁硼废料铁渣还原酸浸液氨法制备铁红

钕铁硼废料盐酸优溶法提取稀土过程产生大量的铁尾渣中含有少量的稀土和钴等有价金属以及大量的氧化铁,回收再利用价值高。团队前期采用还原酸浸的方法从铁尾渣中提取稀土、钴,可有效解决废渣中稀土残留量高的难题,但是还原酸浸液中含量丰富的硫酸亚铁尚未得到有效利用。含铁量高的废液,一般用来制备颜料级铁红。目前,氨法工艺流程是一种环保型且具有发展前景的工艺。然而,氧化制备γ-FeOOH晶种的窗口窄,易出现混晶和形貌不均匀等问题,对工艺条件的控制较苛刻。过程影响因素复杂,定向诱导结晶调控难,需要进一步分析氧化合成过程。以钕铁硼废料铁尾渣酸浸液为原料,NH_(3)·H_(2)O为沉淀剂,采用空气氧化的方法制备前驱体γ-FeOOH活性晶种。首先,通过氨水调溶液pH值,中和沉淀法除去对晶种形貌影响较大的杂质离子Al^(3+),提高晶种的活性。其次,通过热力学稳定区抑制杂相Fe_(3)O_(4)及α-FeOOH的生成,制备具有单一晶型、针状结构且分散均匀的活性晶种。最后,明确氧化合成铁红的工艺参数条件并探讨合成机理。该工艺可产生附加值产品—颜料级铁红,实现钕铁硼废料铁尾渣还原酸浸液的再利用。

高镁磷尾矿硝酸分解过程研究

在磷尾矿回收利用过程中,酸解是至关重要的一步,而酸解的效率往往并不理想。针对该问题,以湖北某高镁磷尾矿为对象,对其硝酸分解过程的反应热力学进行了分析,研究了不同参数条件对磷尾矿硝酸分解效果的影响,并对酸浸液和酸浸渣进行了成分分析。研究结果表明:在硝酸溶液体系下,高镁磷尾矿的分解反应在常温下可自发进行,液固比为3.8∶1,硝酸浓度为34%的条件下,磷尾矿的分解效率最高,达到了91.84%,此时白云石基本已溶解完全,而部分氟磷灰石未完全溶解。

Fenton铁泥资源化利用

Fenton铁泥是指Fenton法处理废水后产生的污泥,经检测含有大量铁元素和有机物,如果不经过良好的处理,不仅污染环境,而且更是一种资源的浪费。将铁泥中的铁回收,制备铁系产品,可以实现资源化利用。本文针对Fenton铁泥的特性,选择废酸浸液还原法制备硫酸亚铁,并研究其制备条件和影响因素,主要包括废酸浓度、废铁屑粒径、反应温度等。

赤泥磷酸浸出液中稀土的萃取行为研究

赤泥是铝土矿生产氧化铝过程中产生的固体残渣,含有铁、硅、铝、钛及稀土等多种有价组分。在已预先分离赤泥中大部分铁、硅、铝、钛的前提下,采取溶剂萃取的方式对赤泥磷酸浸出液中的稀土作进一步分离与纯化,研究了在中性磷型萃取剂TBP、酸性磷型萃取剂P204和P507分别作用下,稀土La、Ce、Sc、Y以及主要杂质组分Al、Fe、Ti、Ca的萃取行为,结果表明:TBP对稀土的萃取效果较差,P507对稀土Sc、Y及杂质Fe、Ti的萃取能力较强,P204萃取稀土的能力优于P507;采用质量分数2%P204作为萃取剂,在溶液pH为1.5、相比为1∶3的条件下,磷酸浸出液中Sc、Y的萃取率分别为90%、99%,La、Ce及杂质Fe、Al、Ti、Ca萃取率均低于5%;将P204质量分数升至20%,La、Ce萃取率可分别达到85%、95%。因此可通过采用P204分步萃取的方式有效分离磷酸浸出液中的稀土。

离子交换树脂回收酸性溶液中钨的试验研究

白钨矿酸浸过程钨以钨同多酸形式产出,此分解方法为白钨矿冶炼提供了新的途径,但后续从钨同多酸浸出液中回收钨是关键。本文比较了不同阴离子交换树脂对钨同多酸溶液的吸附行为,确定大孔弱碱性阴离子交换树脂D301为最佳树脂。主要考察了D301树脂用量、溶液pH值、吸附温度、钨浓度和吸附时间对树脂吸附钨的影响。结果表明,在树脂用量为5倍理论量,溶液pH值为2~3,吸附温度为40℃,钨(WO_(3))浓度为50~100g/L,吸附时间为240min的条件下,D301树脂对钨同多酸溶液中的钨吸附率达99.4%以上。同时,研究了载钨树脂的解吸行为,结果表明,对D301载钨树脂解吸效果最好的解吸剂种类为NaOH溶液,在NaOH溶液用量20mL、浓度4mol/L以及解吸温度50℃、时间60min的条件下,钨的解吸率可达97.94%。

硅藻土酸浸液制备聚合硫酸铝铁絮凝剂及性能研究

以黑龙江某硅藻土酸浸液为原料,采用氧化-水解-聚合法制备聚合硫酸铝铁絮凝剂,并以4g·L^(-1)的高岭土悬浮液为模拟废水,考察聚合硫酸铝铁的絮凝性能。结果表明:在双氧水用量为0.01V,pH值为2.5,聚合温度为65℃,聚合时间为2.5h,转速为150r·min^(-1),熟化时间为24h的条件下,可获得13.75g/50mL的淡黄色聚合硫酸铝铁固体;模拟废水对照组在5min内透过率的提高速率达12.8%·min^(-1),30min内沉降97mm,空白组没有明显变化,聚合硫酸铝铁表现出明显的絮凝性能,为硅藻土酸浸液的清洁利用提供了可行性技术方案。

羟肟类萃取剂高效选择性分离高酸多杂钒页岩酸浸液研究

为积极响应国家“双碳”目标,开发高效选择性钒页岩酸浸液净化分离工艺对页岩提钒行业意义重大。在本研究中,从溶液pH值、杂质离子(铁、铝和镁)浓度和反萃剂3个因素对比了新型羟肟类萃取剂Mextral 984H和有机磷类萃取剂P204的萃取行为。结果表明,Mextral 984H的最佳萃取pH值在0.5-1.5,P204的最佳萃取pH值在1.5-2.4,相比于P204,Mextral 984H与钒形成的钒萃合物结构更稳定,钒氧键键长值更小,分子间隙更大,钒萃合物在酸性环境中更容易稳定存在。Fe(Ⅲ)、Al(Ⅲ)和Mg(Ⅱ)对Mextral 984H萃取V(Ⅴ)的影响较小,而在P204中,Fe(Ⅲ)对V(Ⅳ)的萃取影响较大,将Al(Ⅲ)和Mg(Ⅱ)的浓度控制在10 g/L以下,可降低Al(Ⅲ)和Mg(Ⅱ)的共萃率。碳酸钠和草酸对Mextral 984H负载有机相的单级反萃率均超过80%。

用Mextral 6106H从酸性料液中萃取钒

研究了用Mextral 6106H从酸性料液中萃取钒,考察了料液酸度、萃取温度、萃取时间、萃取剂浓度、萃取相比、反萃取剂组成等对钒萃取的影响,测定了Mextral 6106H对钒的饱和萃取量。结果表明:Mextral 6106H在酸性条件下对V(Ⅴ)具有良好的选择萃取性能,料液硫酸质量浓度在20~150 g/L范围内,钒萃取率大于95%;钒萃取率随萃取剂浓度和萃取相比V_(o)/V_(a)增大而升高;10%Mextral 6106H对钒的饱和萃取量为3.76 g/L;Mextral 6106H萃取钒速度较快,与料液接触3 min左右萃取反应基本达到平衡;用20 g/L NaOH溶液或氨水反萃取钒,钒反萃取率大于96%。该萃取剂对钒的萃取效果较好。

从铜渣中获得工业醋酸铜(Ⅱ)溶液的常压浸出条件和浸出动力学研究

从铜渣中回收有价金属的技术虽然很多,但其经济和环境相容性都不理想。用双氧水和有机酸乙酸研究了铜渣中金属在常压下的溶解行为。该渣为转炉渣和闪速炉渣的混合物,含Cu 6.74%,Zn 4.34%,Fe 36.45%。常规的常压浸出实验在100 mL的玻璃烧杯中进行,在磁力搅拌器中使用涂有聚四氟乙烯的磁性搅拌棒。在最佳浸出条件下,铜提取率为98.04%,锌提取率为28.8%,铁提取率为2%。拉曼光谱显示Cu^(2+)/Zn^(2+)与AcO^(-)(乙酸)存在配位。溶解过程用一级动力学方程描述。表观活化能为23.7 kJ/mol,表明溶解过程受扩散控制。H_(2)O_(2)和CH_(3)COOH的反应级数分别为1.24和0.1。本文提出的湿法冶金新工艺简单、环保,在常规条件下从铜渣中获得醋酸铜溶液的性能明显优于其他方法。