冶金污泥中铜锌镉铅的氨水和碳酸铵选择性浸出分离

为了将冶金污泥中的有价金属资源化并合理回收与利用,用采用氨水和铵盐复配对冶金污泥中的铜、锌、镉和铅进行选择性浸出,并且通过单因素条件试验分别考察铵盐种类、氨水和铵盐复配体系作为浸出剂中氨水和铵盐各自的浓度、浸出反应的温度和浸出反应时间等因素对铜、锌、镉和铅浸出率的影响,从而通过对比得出最佳的金属浸出工艺条件:复配体系中铵盐选择为碳酸铵,浓度为0.5mol/L,缓冲剂氨水浓度为3mol/L,反应温度为50℃,浸出反应时间时间为120min.在此条件下,铜、锌和镉的浸出率分别为91.51%、85.13%和89.51%,而铅的浸出率则低于6.00%,本工艺可以实现铜、锌和镉的回收同时可以实现对铅元素的基本分离.     

羊拉铜矿综合回收工艺研究

采用湿法冶金同浮选工艺联合,酸浸—萃取—电积—渣浮选联合工艺综合回收氧化铜矿中的有价元素:酸浸浸出矿物中的氧化铜,通过萃取、电积工艺生产电积铜,浸出渣浮选,回收渣中的残余铜矿物及有价金属金、银,提高氧化矿综合利用价值。     

含铟锌渣浸出和萃取铟的研究

湿法炼锌产出的锌渣含铟达700~850 g/t,采用两段酸浸,铟的浸出率可达90%以上,并提出了酸浸的工艺流程和最佳浸出条件.分别对酸液和有机相采用三级逆流萃取和反萃,铟的萃取率和反萃率分别达98.5%和99%以上,并提出了最佳萃取和反萃条件.     

鼓风炉渣碳基还原回收铅、锌、铁及尾渣环境特征

针对云南省个旧市历史遗留鼓风炉渣的安全处置，采用碳热还原-磁选方法回收铅、锌和铁，并高温固化获得稳定化尾渣.研究了温度、时间、还原剂用量对铅、锌和铁的回收影响，碳基还原过程铅、锌、铁的还原行为和磁选尾渣的环境风险.结果表明，在温度1 300℃、还原时间60 min、还原剂用量4%的条件下，铅、锌的挥发率分别达91.97%和96.96%,铁的金属化率96.94%;在磁场强度为250 MT的磁选条件下，铁的回收率78.93%,铁精矿中铁品位为90.94%.SEM-EDS和XRD分析结果表明：鼓风炉渣经高温碳热还原后，渣中铅以硫化物和铅铁矾的形式镶嵌于硅酸盐晶体中，渣中其他重金属则均匀分布在硅酸盐晶体中.磁选尾渣中铅、锌、砷、镉浸出值未超过国标GB 5085.3-2007规定限值；Tessier重金属形态分析结果显示尾渣中铅、锌、砷、镉残渣态比例相比于鼓风炉渣增大，表明鼓风炉渣碳热还原后环境风险降低，实现了鼓风炉渣的资源化及无害化.     

盐酸对冶金污泥中铜锌镉铅的浸出工艺优化

为了能够充分回收利用冶金污泥中的有价金属,采用盐酸作为浸取剂浸出污泥中的重金属,并进行浸出工艺的优化.首先对污泥性质进行分析,分别采用烘干法测定冶金污泥的含水率,用X射线荧光光谱仪测定试样中金属成分及质量分数,用X射线衍射仪对试样中各元素的物相特征进行定性和定量分析.结果显示:污泥含水率为75.88%;干污泥含铜和锌的质量分数分别是1.51%和1.71%;污泥矿物相中铜主要以单质形式存在,锌主要以闪锌矿形式存在.然后采用盐酸作浸取剂,在单因素条件下进行浸出反应.研究了冶金污泥中铜、锌、镉、铅等重金属的浸出规律,并考察了浸出温度、浸出时间、盐酸浓度、液固比、粒径等因素对浸出率的影响.盐酸浸出污泥中重金属最佳工艺参数:浸出温度为25℃,浸出时间为10 min,盐酸浓度为1mol/L,液固比为25∶1(mL/g),干污泥粒度小于150μm.在此条件下,铜、锌、镉、铅的浸出率可分别达到84.4%、88.1%、98.8%、85.4%.盐酸浸出最佳工艺条件的确定,对工业应用有一定实用价值.     

硫脲法从锌的酸浸渣中回收银

研究了从湿法炼锌酸浸渣中用硫脲浸出银的工艺及机理，对浸出过程中的各种影响因素如矿浆浓度、浸出剂浓度、反应温度、反应时间、ＰＨ值等分别进行了试验研究和分析讨论，给出了最佳工艺条件，在此条件下，银浸出率达８９％。     

酸性条件对湖北某银矿固体废物重金属浸出特性

为了解矿业活动中的固体废物在酸性条件下重金属浸出浓度对环境的影响,采用硫酸硝酸-浸出毒性实验方法,研究了湖北某银矿3种不同的固体废物废石、尾矿、氰化残渣在不同pH条件下的重金属浸出浓度及浸出率的变化.结果表明锌、铅、镉在pH=2的条件下浸出浓度最高,采矿废石中的铜在pH=2的条件下浸出浓度最高,而浮选尾矿和氰化废渣中的铜在pH=3的条件下浸出浓度最高.铜、锌、铅、镉在pH=2的环境中浸出率较高.不同样品中,重金属的浸出浓度与重金属所对应的浸出率不一定成正比关系.矿山固体废弃物释放的重金属元素会对生态环境造成影响,需要加强监测与管理.     

用AC法从高锑低银类铅阳极泥中回收银和铅

用AC法处理高锑低银类铅阳极泥，其氯化浸出渣经转化脱氯、硅氟酸浸铅、氨水浸银和水合肼还原，得到含Ag大于95％的银粉，铅以硅氟酸铅溶液返回电解精炼．在V苏打溶液／m浸出渣＝4mL／g，n苏打实＝1．6n苏打理，转化时间为4h及温度为80℃的最佳转化条件下，铅、银、氯的平均转化率为91．42％；在V(H2SiF6)／m浸出渣＝4mL／g，浸出时间为1h，温度为50--60℃的最佳浸铅条件下，硅氟酸浸铅率为85.74％--86．07％，硝酸浸铅率大于95％；在浸银过程中，银的浸出率约为94．o％，沉银率约为98．0％．在整个工艺中，银的直收率及总回收率分别为93．63％及98．80％，铅直收率为85．91％，总回收率98．99％．     

从银锌渣真空蒸馏回收银和铋的研究

粗铋火法精炼过程中采用加锌除银工艺而产生大量的银锌渣,银锌渣内含Ag、Bi等贵金属.目前主要采用熔析的方法回收其中的Ag和Bi.本文采用真空蒸馏的方法对银锌渣进行二次资源回收,通过实验研究确定真空蒸馏回收Ag和Bi的最佳实验条件为：炉内压强为1～30 Pa,蒸馏温度为900℃,保温时间为2 h.在此条件下,粗银含银量为66.73%,Ag的回收率为97.88%,粗铋含铋量为91.99%,Bi回收率为93.46%.采用真空蒸馏回收Ag和Bi可以大大降低Zn的加入量、降低银锌渣的产出量;同时减少银锌渣烟化、还原流程处理量,降低精铋生产能耗.     

铅锌矿石中有价金属的综合回收

根据矿石性质,对铜铅品位极低的铜铅锌矿石中的有价金属进行了综合回收试验.结果表明:用部分混合-分离浮选工艺流程,能有效回收锌金属,同时综合回收铜、铅、银、硫铁等金属.在铜铅分离和选锌作业中采用了新型磺化腐植酸类抑制剂Fs,提高了铜精矿和锌精矿的质量.试验证明Fs是一种高效的铅硫砷抑制剂.     

Oxygen pressure acid leaching of Gacun complex Cu concentrates

The treatment of the Gacun complex Cu concentrate with high contents of Pb, Zn, Ag, etc by oxygen pressure acid leaching was studied. It is unusual that tetrahedrite, whose treatment was rarely studied, is the primary copper mineral of the concentrates. Most of silver also occurs in the mineral. The optimum operating parameters of oxygen pressure acid leaching were established by conditional tests. Pilot scale test was carried out under the parameters, and the leaching rates of copper and zinc are as high as 97.10% and 89.83% while lead and silver are transformed into sulfate and sulfide respectively and stay in leaching residue. The copper and zinc in lixivium were reclaimed by extraction-electrowinning and purification-electrowinning, respectively, and the lead and silver in the residue were reclaimed separately by chloride leaching and thiourea leaching. The extraction rate of copper achieves 96%, and the leaching rates of lead and silver reach 90% and 95%, respectively.     

Ag recovery from copper anode slime by acid leaching at atmospheric pressure to synthesize silver nanoparticles简

In this paper, recovery of silver from anode slime of Sarcheshmeh copper complex in Iran and subsequent synthesis of silver nanoparticles from leaching solution is investigated. Sarcheshmeh anode slime is mainly consisted of Cu, Ag, Pb and Se. Amount of Ag in the considered anode slime was 5.4% (by weight). The goal was to recover as much as possible Ag from anode slime at atmospheric pressure to synthesize Ag nanoparticles. Therefore, acid leaching was used for this purpose. The anode slime was leached with sulfuric and nitric acid from room to 90 °C at different acid concentrations and the run which yielded the most recovery of Ag was selected for Ag nanoparticles synthesis. At this condition, Cu, Pb and Se are leached as well as Ag. To separate Ag from leach solution HCl was added and silver was precipitated as AgCl which were then dissolved by ammonia solution. The Ag nanoparticles are synthesized from this solution by chemical reduction method by aid of sodium borohydride in the presence of PVP and PEG as stabilizers. The synthesized Ag nanoparticles showed a peak of 394 nm in UV–vis spectrum and TEM images showed a rather uniform Ag nanoparticles of 12 nm.     

Mineralogical characterization of a polymetallic sulfide ore to improve silver recovery

Based on the mineralogical characterization for the polymetallic sulfide ore, the way to improve silver recovery was studied. The results showed that silver was the most valuable metal whose grade was 448.82 g/t Ag, while 0.118% Cu, 1.65% Pb and 1.06% Zn may be comprehensively utilizated. The main silver-bearing minerals were argent and aregentite which accounted for 87.18% of total silver. Argentite and other metal minerals were distributed in the gangue minerals in complex forms. Argentite grains of 33.76% minus 50 μm indicated that a fine grinding scheme was necessary to enhance the degree of dissociation, and meanwhile selective grinding must be considered to prevent a complete grinding of coarse grains. The optimum regrinding fineness in the Cu flotation was determined as 73% minus 37 μm, while grains of 68.5% minus 74 μm in one-stage grinding remained unchanged as much as possible. Consequently, silver recovery increased to 2.68%, as well as the content of Pb simultaneously decreased from 7.26% to 2.68% in the Cu concentrate. From the lead pyrometallurgical point of view, recovering larger amounts of silver and lead at the expense of decreasing the grade of lead to a suitable level is not only economically viable for the plant, but also convenient for subsequent processing. Silver and lead recovery increased to 13.18% and 12.58%, respectively, while the Pb grade decreased from 53.1% to 46.12% for the Pb concentrate.     

由龙头汪金矿硫精砂中综合回收金银铜的研究

研究探讨了从硫精矿中综合回收金银铜的途径．确定了最易实现工业化的浮选流程。在原硫精矿害Cu、Au、Ag、S分别为0．67%、5．01g／t、17．23g／t、35．17%的情况下，经氧化浮选后，可获得铜金精矿；βCu=15．59％．βAu=112g／t．βAg=210g／t，εCu=77．74%，εAu=40.72%，浮选尾矿中βs=35．42%，εs=97．31%，可作为硫精矿出售。     

淋洗剂对土壤铅淋洗效率及养分损失的研究

利用3个浓度的乙二胺四乙酸二钠(EDTA-Na2)、苹果酸(MA)和柠檬酸(CA)3种淋洗剂对某铅选矿厂周围铅污染土壤进行了模拟淋洗研究,测定了铅的去除效率和土壤速效氮、速效磷和有机质的流失量。研究结果表明,研究区域土壤Pb污染较为严重,平均含量达到1 389 mg/kg。在同种浓度处理下,土壤铅的淋洗去除效率依次为EDTA-Na2>柠檬酸(CA)>苹果酸(MA)。随着淋洗液浓度的增加,铅的淋洗去除效率增加,土壤中速效氮、速效磷和有机质的淋洗流失量也逐渐增加。同种浓度下不同淋洗剂淋洗的养分损失量顺序不完全一致。结果表明,在4种淋洗剂中,EDTA-Na2是最有效的土壤铅污染淋洗剂,在强化植物修复方面也有很好的应用前景。     

高锑低银铅阳极泥湿法提银及综合回收的研究

对高锑低银铅阳极泥进行了湿法处理的研究,提出了低温空气预氧化,亚硫酸钠浸银－甲醛还原提银,浸出液制取立方锑白,并综合回收其他金属的工艺。通过实验Ａｇ,Ｓｂ,Ｐｂ的回收率达到９８％,锑白达到一级锑白的标准     

氨浸置换法资源化废杂铜的研究

采用碳铵浸取-置换沉积新方法资源化、无害化回收废杂铜.考察浸取时间、氨水浓度、碳酸铵用量、催化剂用量对浸取效果的影响,并讨论还原剂用量、置换时间及搅拌速度对沉积过程的影响.结果表明:在(NH4)2CO3:6.5 g,NH3.H2O:6 mol/L、浸取催化剂:12 mL、浸取时间3 h的最优条件下,铜、锌的浸取率分别达到93.12%、95.03%,而伴生元素留在滤渣中.二段置换沉积过程中,在最佳工艺条件下,制备出产品纯度与附加值高的铜粉和七水硫酸锌.铜的回收率达到98.3%.该工艺具有操作简单、生产效率高、成本低、无污染等特点.     

常压酸浸高冰镍的动力学研究

本文是关于常压酸浸高冰镍的动力学研究.实验考察了粒度、温度、硫酸浓度和氯离子浓度对镍浸出速率的影响.结果表明,在硫酸体系中选择性地浸出镍不仅在热力学上是可能的,而且反应速率快,完全能达到一次分离镍铜的目的.本文采用特殊的处理方法,将总镍浸出率R转换为Ni_3S_2中镍浸出率R~(?),从而导出实验条件下的动力学方程式.而浸出过程受通过产物层的固膜扩散控制.     

含铅锌银硫精矿湿法综合回收工艺研究

采用氯盐选择性地从含铅锌银硫精矿中浸出铅锌银，利用金属氯化物的化学流行性、合物的稳定性及溶解度的差异，从浸出液中提取铅银及锌金属。