铜烟尘碱浸渣硫酸浸出锌铜试验研究

对Na OH浸出铜烟尘后得到的渣进行硫酸浸出锌、铜试验研究,最终得到硫酸浸出优化条件为:初始硫酸质量浓度170 g/L、液固比4∶1 m L/g、浸出时间3 h、搅拌转速400 r/min、温度90℃,锌浸出率为:95.45%,铜浸出率为96.72%。通过试验研究,为下步进行综合回收铜烟尘中锌、铜、铅、铋、锡等有价金属提供基础。     

磷酸体系应用于失效磷酸铁锂电池正极材料回收的研究

以H_3PO_4-H2O_2溶液对除铝后的失效磷酸铁锂电池正极材料进行浸出锂实验,采用ICP-OES测定浸出液中Li+和Fe3+浓度,研究了H2O_2及H_3PO_4加入量、液固质量比(L/S)、反应温度、搅拌转速、反应时间及体系终态pH值对Li浸出率的影响,并对终态pH值为3.5得到的滤渣进行XRD分析,结果表明,Li浸出率随H2O_2及H_3PO_4加入量的增加而增大,但当H2O_2与H_3PO_4用量分别高于1.2倍、1.1倍反应计量时,锂浸出率增速趋缓;随着液固质量比的增大,Li浸出率呈现先增大后减小的趋势;在30~60℃反应温度对Li浸出率影响不明显;Li浸出率随搅拌转速的提高和反应时间的延长而增大,但搅拌转速高于30 r×min~(-1)、反应时间超过3.0 h后Li浸出率变化不明显;体系终态pH为3.5时,锂浸出率为99.21%、铁沉淀率为99.99%,浸出渣为Fe PO_4·2H2O。     

从锂离子电池回收钴铜物料盐酸浸出机理研究

对由失效锂离子电池焙烧得到的物料进行了化学物相和SEM分析,利用热力学原理研究了使用盐酸浸出物料时各物相的反应机理,并进行了试验证明。分析表明物料含高品位钴和铜,主要以金属和不同价态的氧化物形式存在。除CoO、Co和CuO易溶于酸外,Co能优先置换沉淀已溶解的Cu2+,Co3O4和Co2O3能被盐酸还原浸出,Cu2O会发生歧化反应,Cu最终被氯化浸出,部分铜在浸出体系中经历了一个溶解-置换沉淀-复溶解的过程。热力学研究表明,使用盐酸浸出物料中的钴和铜是可行的。钴和铜成分在浸出过程中有相互影响,有利于提高钴和铜的浸出率。盐酸浸出试验证明了分析结论,当使用2 mol/L盐酸318 K下浸出6 h、液固体积质量比为(20∶1)mL/g、搅拌转速200 r/m in时,钴和铜的浸出率分别达到99.3%和95.9%。     

铜蓝的细菌氧化浸出

研究了福建紫金山铜矿中主要目的矿物之一铜蓝的细菌浸出过程的影响因素,考察了铜蓝纯矿物的浸出特性. 实验室条件下细菌浸出铜蓝纯矿物的适宜条件为：接种量100%,矿浆浓度<5%,初始Fe2+浓度4.0 g/L. 20 d浸出周期内铜蓝浸出率可达60%以上. 通过向纯矿物浸出体系中添加Fe3+、黄铁矿和H2O2,探讨提高溶液氧化电位以强化浸出效果的可能性. 结果表明,添加Fe3+和H2O2对于提高溶液的氧化性效果不显著,同时影响细菌的浸出. 添加黄铁矿则能有效提高浸出过程的氧化电位,以1:2或1:1质量比添加黄铁矿能明显加快铜蓝的细菌浸出速率.     

某难处理氧化铜矿酸浸实验及动力学分析

针对以硅孔雀石为主的高结合率、高钙镁难处理铜矿的进行了酸浸动力学研究,考察了温度、硫酸浓度、搅拌强度和矿石粒径对铜浸出率的影响.结果表明:铜浸出率随温度和硫酸浓度的增大而提升,搅拌强度对铜浸出率影响较小,铜浸出率随矿石粒径的减小先增大后减小,这可能是由于原矿钙镁含量高,当磨矿细度过细钙镁充分解离,一旦矿石和硫酸接触,钙镁和硫酸迅速反应消耗大量的酸,导致铜的浸出率降低.采用SEM-EDS和XRD对浸出前后矿样进行表征,结果表明碳酸钙与硫酸反应生成硫酸钙沉积在颗粒表面形成固态产物层,阻碍浸出反应.动力学分析表明该浸出过程受固态产物层扩散控制,反应表观活化能为11.43 kJ/mol.     

高碱性铜尾矿的黑曲霉生物浸出

以湖南某高碱性铜尾矿为研究对象,进行了黑曲霉摇瓶浸出实验,研究了浸出时间和PSA培养基成分、含量对铜浸出的影响. 结果表明,浸出时间为7 d时,铜浸出率最高,随浸出时间延长,铜浸出率显著下降. PSA培养基中的马铃薯和蔗糖含量对铜浸出有明显影响,马铃薯含量为200 g/L、蔗糖含量为20 g/L时,铜浸出率最高. 在接种量0.02%(j)、矿浆浓度50 g/L、温度30℃、转速200 r/min、浸出时间7 d、马铃薯和蔗糖含量分别为200 g/L和20 g/L条件下,铜浸出率可达79.03%.     

CO2对CuO/ZnO/Al2O3催化剂前体老化及催化性能的影响

采用并流共沉淀法制备CuO/ZnO/Al2O3甲醇合成催化剂前体,在通入CO2条件下老化,采用XRD、FT-IR、DTG、H2-TPR、XPS等表征手段对制备的前体及焙烧后的催化剂进行表征,研究不同CO2通入量对前体晶相转变、微观结构及其焙烧后催化性能的影响。研究结果表明,老化阶段通入CO2后,沉淀母液的pH值趋于7,产生CO32?离子,进而影响Zn2+的沉淀,促进Cu2+进入Zn5(CO3)2(OH)6晶格中取代Zn2+形成绿铜锌矿(Zn,Cu)5(CO3)2(OH)6物相,有助于增强焙烧后催化剂的Cu-Zn之间协同作用,增加活性组分Cu分散度。CO2通入量为40 mL/min时,制备的催化剂在浆态床合成甲醇过程中表现出良好的催化活性和稳定性,甲醇时空收率（STY）达到301.78 g/(kg?h),失活率仅为0.15%/d,与未通入CO2辅助老化制备的催化剂相比,时空收率提高了9.72%,平均失活率降低了33.33%。     

氯化铁浸出废金属回收海绵铜的工艺研究

采用氯化铁选择性浸出工艺对废金属进行综合利用,制备氯化铁及海绵铜。主要考察了废金属浸出、海绵铜洗涤工艺的可行性,并确定浸出工艺的最佳条件。结果表明:在搅拌速度150 r/min、氯化铁溶液质量分数29.91%、浸出剂量为理论量105%、反应温度60℃、反应时间1.0 h的条件下,铁浸出率为94.86%,铜浸出率为3.57%。浸出渣经盐酸溶液洗涤,能有效提高海绵铜的品质。     

氧压条件下硫酸溶液浸出锡铜渣试验研究

氧压条件下硫酸溶液浸出锡铜渣试验，开展了初始酸度、浸出液固比、反应温度、反应压力、反应时间以及浸出液返浸等技术参数对铜浸出率、锡入渣率的影响，试验结果表明：采用的技术参数为初始酸度150 g/L,液固比5∶1,反应温度130℃,反应压力1.2 MPa,反应时间4 h,浸出液可返浸，铜入液，锡入渣，浸出渣中的铜质量分数小于2%,锡入渣质量分数高达99%以上，浸出液可返浸，较好地实现锡铜分离，是处理锡铜渣的一种有效手段。     

含汞加压浸出锌渣浮选硫精矿中分离富集有价元素的工艺研究

利用Na_2S浸出-CO_2沉淀法从浮选硫精矿中分离和富集有价金属汞和锌,并对元素硫的回收进行了研究。通过正交设计对影响浸出过程的Na_2S浓度、液固比、浸出时间和温度等因素进行优化。研究结果表明,以浓度1. 5 mol/L Na_2S溶液为浸出剂,在6∶1的液固比条件下常温浸出30 min,元素硫浸出率可达98%以上,同时有价金属锌和汞在浸出渣中的质量分数为原矿石的5倍以上,富集率高于98%。向浸出液中通入CO_2气体,充分搅拌溶液,在CO_2流量为200 m L/min、通气时间为150 min的条件下,元素硫从溶液中析出,回收率可达到97. 67%。     

Leaching Kinetics of Calcium Vanadate by Na2CO3 Solution

Leaching kinetics of calcium vanadate by Na2CO3 solution was studied. Kinetic equation was established according to the variation of VO3-concentration with time during the leaching process. The influences of initial pH value and stirring speed on reaction rate constant were examined and the corresponding apparent activation energy was calculated. The results indicate that the leaching process is a 0.68 order reaction, and the reaction rate constant 8.64×10-6 mol/(L-s). It increases with the increase of pH value and stirring speed. And the dissolution rate of calcium vanadate also increases. The apparent activation energy is 38.98 kJ/mol, and temperature has great influence on the leaching rate of calcium vanadate.     

Investigation of selective leaching and kinetics of copper from malachite ore in aqueous perchloric acid solutions

In this study, the leaching kinetics of malachite in perchloric acid solutions was investigated. The dissolution behaviors of copper, zinc, and iron in the ore matrix were determined at different acid concentrations and reaction temperatures. It was observed that the concentration of perchloric acid had a major effect on the dissolution of copper, zinc, and iron. It was determined that the effect of temperature on the dissolution of these species was not as significant as concentration impact. The results obtained shown that copper in the ore matrix was completely leached while zinc and iron were partially dissolved in perchloric acid solutions. In addition, the effects of the acid concentration, reaction temperature, stirring speed, particle size, and solid-to-liquid ratio on the leaching of malachite were researched. In these experiments, it was observed that the leaching rate of copper increased with increasing solution concentration, stirring speed, and reaction temperature, and with decreasing solid-to-liquid ratio and particle size. A kinetic analysis was performed, and it was found that the rate of leaching reaction obeyed the mixed kinetic control model in the unsteady state. The activation energy of the leaching process was calculated to be 34.69 kJ/mol.     

硫铁矿烧渣酸浸铜反应动力学研究

研究了硫酸烧渣的硫酸浸铜过程中,搅拌速率、浸出剂初始质量浓度、固液比、浸出温度和矿物粒径对浸出率的影响,并对硫铁矿烧渣浸取铜过程动力学进行了分析。研究结果表明,该浸出过程符合收缩芯模型,与化学反应控制动力学方程式相吻合,浸出反应的表观活化能为39.19 kJ/mol,浸出过程控制步骤为化学反应控制。     

NaHCO3溶液浸出硼精矿中硼的工艺

研究了NaHCO3溶液提取硼精矿熟料中硼的工艺,考察了液固比、NaHCO3用量、浸出温度、浸出时间和搅拌速率对硼提取率的影响. 结果表明,最佳提取工艺条件为液固质量比2.1:1,NaHCO3用量为理论用量的150%,反应温度100℃,反应时间1 h,搅拌速率400 r/min,该条件下硼浸出率达92.88%. 硼精矿熟料的晶形大多是柱状和扁平状,并有微小颗粒附着其表面;终硼泥为很多小晶体堆叠在一起,与硼精矿熟料相比,终硼泥颗粒变小,因此可用收缩核模型描述硼精矿熟料中硼在NaHCO3溶液中的浸出过程. 金云母、遂安石、利蛇纹石和橄榄石是硼精矿熟料的主要物相,而终硼泥出现了MgCO3和Na2Mg(CO3)2物相,遂安石消失.     

Leaching kinetics of copper flotation tailings in aqueous ammonia/ammonium carbonate solution

The experiments of agitation leaching were carried out in aqueous ammonia/ammonium carbonate solution, to recover copper from the flotation tailings of waste copper oxide residue. The main copper minerals contained in the flotation tailings are chrysocolla, malachite, and cuprite, with the copper grade of 1.12%. Effects of lixiviant concentration, solid‐to‐liquid ratio, stirring speed, and reaction temperature on copper leaching ratios at various time were investigated. It is found that the leaching ratio almost cannot be affected by time after 90 min of leaching. The optimised processing conditions have been determined, under which the leaching ratio of 70.6% is obtained. Kinetics analysis indicates that the copper leaching ratio is controlled by diffusion through the product layer in the initial 60 min of leaching, and corresponding measures to strengthen the copper extraction is proposed, with the activation energy of 32.3 kJ/mol. © 2012 Canadian Society for Chemical Engineering     

磷酸分解磷矿过程中金属元素的浸出规律研究

探究了以磷酸分解磷矿,关键酸解工艺参数对磷及Fe、Al、Mg、Pb、As浸出的影响规律,并从热力学角度进行了分析。结果表明,磷矿内磷及Fe、Al、Mg浸出率随磷酸质量分数、反应温度、反应时间和液固比的增大而增大,搅拌速度影响不明显;Pb浸出率随磷酸质量分数、反应温度和液固比的增大而增大,搅拌速度、反应时间影响不明显;As浸出率随反应温度升高呈先增大后减小趋势,随反应时间增加略有减小,磷酸质量分数、搅拌速度和液固比影响不明显。控制磷酸质量分数为30%（以P₂O₅计）、反应温度为80 ℃、搅拌速度为300 r/min、反应时间为150 min、液固质量比为10∶1,在此条件下,磷及Fe、Al、Mg、Pb、As的浸出率分别为98.65%、68.56%、48.54%、95.84%、32.85%和84.62%。通过热力学分析表明磷矿内Mg、As浸出率较高,Pb浸出率较低,而Fe、Al浸出率大小主要取决于磷矿中褐铁矿及高岭土含量。     

超声辅助碱浸铜冶炼烟灰中铜砷分离

采用超声辅助Na₂S-NaOH浸取体系对铜冶炼烟灰进行研究,在NaOH、Na₂S与烟灰质量比0.4：1,液固比20：1,反应温度75℃,反应时间5 min,超声功率80 W,搅拌速率400 r·min^-1条件下,As浸出率为88.81%,Cu浸出率为0.025%,实现了Cu和As的有效分离。采用该方法处理后,与单独碱浸相比,As浸出率提高9.21%,烟灰中As含量由0.85%降至0.58%,Cu含量由2.21%增至2.30%,且As浸出毒性浓度由12.66 mg·L^-1降至2.84 mg·L^-1,为烟灰的资源化利用创造了条件。超声辅助碱浸除砷动力学满足收缩核混合反应控制模型,表观活化能0.114 kJ·mol^-1。XRD、XPS和重金属形态分析结果表明,超声空化作用可使As（Ⅲ）氧化为As（Ⅴ）,有利于As浸出,故超声过程强化有利于Cu和As在碱浸体系中的选择性分离。     

蔗髓低温还原焙烧-浸出低品位软锰矿工艺

以蔗渣造纸工业废弃物蔗髓为还原剂,研究了低温焙烧还原浸出软锰矿的新工艺. 考察了蔗髓与软锰矿中锰的质量比、焙烧时间、焙烧温度、搅拌速率、浸出温度、浸出时间、H2SO4浓度和液固比对锰浸出率的影响,并分析还原焙烧过程. 结果表明,锰浸出率随蔗髓用量、焙烧时间、焙烧温度、搅拌速率、浸出温度、浸出时间、H2SO4浓度和液固比增加先增加然后基本保持不变. 蔗髓热解生成还原性气体有机物将软锰矿中高价锰氧化物MnO2还原为低价MnO. 适宜的焙烧还原浸出条件为：蔗髓/锰质量比0.62:1、还原焙烧温度350℃、还原焙烧时间60 min、浸出搅拌速率200 r/min、浸出温度60℃、浸出时间40 min、H2SO4浓度3.0 mol/L、液固比6 mL/g. 在此条件下,软锰矿的浸出率可达97%.     

机械力强化作用下轻烧氧化镁碳化过程的传质与反应动力学研究

The carbonization of magnesium oxide particles by CO2 was investigated using a stirring mill reactor. The effects of the system temperature, stirring rotation speed, influx rate of CO2 and initial diameter of the magnesium oxide particles on the carbonization process were determined, The results show that the system temperature and the stirring rotation speed are the most significant influencing factors on the carbonization rate. The determi-nation of critical decomposition temperature (CDT) gives the maximum carbonization rate with other conditions fixed. A theoretical model involving mass transfer and reaction kinetics was presented for the carbonization process. The apparent activation energy was calculated to be 32.8kJ·mol-1. The carbonization process is co-controlled by diffusive mass transfer and chemical reaction. The model fits well with the experimental results.