二氧化锰涂层钛阳极的研制

本文研究了用热分解法制得MnO_2涂层钛阳极。大量的试验表明,采取涂敷中间层以及在涂层中添加活性元素两项措施,可有效地提高阳极的导电性能。X射线衍射分析表明,制得的二氧化锰为β-MnO_2,属四方晶系。通过热力学计算,在煅烧温度范围内,所添加活性元素仍以氧化物状态存在,因此催化作用强。工厂试验表明,所研制的Ti/MnO_2阳极,与传统的Pb-Ag阳极相比,槽电压可降低0.5V,节电16％。     

湿法冶金中钛基二氧化锰阳极的研究

研究了钛基二氧化锰阳极涂层的工艺条件．并对有关物理化学性能进行了测试．在钛基体和二氧化锰涂层之间涂覆Ｓｎ－Ｓｂ中间涂层能有效地降低槽电压和防止钛基体的钝化，解决了湿法冶金中应用该种阳极存在的难题．所研制的阳极在硫酸盐水溶液的电解过程中，具有优良的电化性能和耐腐蚀性能，降低能耗，提高了产品的纯度．这种阳极可望在锌、铜、镉、锰、镓、铟、钻、镍等金属的电积过程中得到应用．     

碘量法测定软锰矿中的二氧化锰

在硫磷混合酸介质中、碘化钾过量的条件下,软锰矿中的二氧化锰与碘化钾作用定量析出碘,析出的碘可用硫代硫酸钠标准溶液滴定测定.测定结果与标准值完全一致,相对标准偏差＜0.11％.该方法操作简便,快速,准确可靠,结果满意,适用于生产过程分析.     

从低品位氧化锰矿制备纳米二氧化锰工艺研究

以低品位氧化锰矿为原料,制备高附加值的纳米二氧化锰产品。首先采用生物质还原锰矿,在不引入杂质的情况下,将锰矿中的MnO_2还原为MnO后用酸浸取得到硫酸锰溶液;再通过工艺条件控制,在溶液中加入氧化剂后沉淀得到纳米二氧化锰产品。结果表明,纳米二氧化锰的制备工艺优化条件为:氧化剂高锰酸钾和硫酸锰溶液的浓度分别为0.1mol/L和0.5mol/L;高锰酸钾和氧化锰的摩尔比为2∶3;反应温度为80℃,反应时间为3h,控制硫酸锰溶液的pH为6~7时,能够得到分散性较好的蜂窝状纳米二氧化锰。     

二氧化锰浸出方铅矿工艺条件的正交法优化

用正交实验法优化了在盐酸体系中二氧化锰浸出方铅矿精矿的工艺参数。直接分析和方差分析结果表明: 5种工艺参数对铅浸出率影响由大到小的顺序为: 反应体系中总液体与总固体质量比m_总液/m_总固, 二氧化锰与方铅矿精矿质量比m_二氧化锰/m_方铅矿, 盐酸浓度, 反应时间, 反应温度。最佳实验方案组合为:m_总液/m_总固=10、m_二氧化锰/m_方铅矿=1.3、盐酸浓度为3 mol/L、反应时间为60 min、反应温度为80 ℃, 该组合能使方铅矿精矿中的铅浸出率大于99.5%。     

二氧化锰还原法制备锰酸锂材料及其性能研究

采用二氧化锰还原法制备了锰酸锂前驱体, 将前驱体在不同温度下进行热处理, 制得尖晶石型锰酸锂。利用AAS、滴定法、XRD、SEM表征样品的元素含量、晶体结构、形貌和粒径, 并研究了不同热处理温度对锰酸锂电化学性能的影响。结果表明, 通过二氧化锰还原法合成出了具有一定尖晶石结构的锰酸锂前驱体。当热处理温度为800 ℃时, 锰酸锂的导电性最佳, 0.2C放电容量为132.7 mAh/g, 0.5C放电容量为123.9 mAh/g, 循环10次后, 容量衰减5.97%。     

粉煤灰/二氧化锰复合材料对Pb(Ⅱ)的吸附性能

利用多孔粉煤灰(CFA)为载体制备粉煤灰/二氧化锰(CFA@MnO2)复合材料,用以吸附废水中Pb(Ⅱ)。静态吸附试验结果表明:负载MnO₂后,粉煤灰对Pb(Ⅱ)吸附效果显著提高。CFA@MnO₂对Pb(Ⅱ)吸附动力学符合准二级动力学模型,等温吸附过程符合Langmuir单层吸附模型,最大吸附量为89.28 mg/g。热力学参数ΔH⁰为18.916 kJ/mol,且ΔG⁰<0,表明吸附过程是吸热的且自发进行。     

二氧化锰和硫化矿同时发电浸出的初步探索

将发电原理引入二氧化锰和硫化矿的同时浸出过程,研究镍精矿、方铅矿、闪锌矿、铜精矿和黄铁矿等硫化矿与MnO2同时发电浸出过程。结果表明,适当组装发电浸出电池,可使两种金属离子有效浸出和分离,同时获得电能。所用电极在负载9,9Ω放电时,稳定放电电流及电压依次按镍精矿→方铅矿→闪锌矿→黄铁矿→铜精矿减小,金属浸出率依次按方铅矿→镍精矿→闪锌矿→铜精矿→黄铁矿减小,锰浸出率依次按镍精矿→闪锌矿→方铅矿→铜精矿→黄铁矿减小。浸出效率偏低,电极结构有待进一步改进。     

化学改性MnO2的电化学性能研究

本文通过化学方法掺入一些离子(Bi3+,Pb2+,Co2+)制备了改性二氧化锰,对样品进行扫描电镜检测、充放电及循环伏安实验。结果表明,掺铋摩尔比为0.1的改性二氧化锰经过80次充放电循环后,电极容量还能保持初始容量的70%,显示了很好的可充性,样品颗粒呈球状或椭圆状,有利于改善二氧化锰的可充性。     

关于2009年第2期《二氧化锰流态化还原试验研究》一文的致歉和声明

由于作者疏漏，致使署名错误，现就本刊2009年第2期第82页刊登的《二氧化锰流态化还原试验研究》一文作如下声明：①本成果是在武汉理工大学余永富院士闪速磁化焙烧学术思想下的研究成果，作者张汉泉为课题的主要参加人之一。②本文研究工作均在武汉理工大学完成，其技术成果为武汉理工大学和长沙矿冶研究院所有，与武汉工程大学无关。③参加本课题研究工作的同志还有长沙矿冶研究院彭泽友工程师、刘小银教授、陆晓苏高工，在此一并致谢。本人对以上疏漏造成的有关误会及损失深表歉意，并真挚地向以上所涉及同志致歉。     

煤基还原焙烧法处理高品位氧化锰矿试验研究

为了有效开发利用海外高品质锰矿资源和提高我国锰系产品的生产水平,以进口高品位氧化锰矿为原料、煤为还原剂,对比研究了还原温度、还原时间与还原剂配比对粒矿、粉矿和内配炭球团矿3种焙烧物料还原率的影响。结果表明,3种焙烧物料的工艺条件略有差异,粒矿焙烧的最佳工艺条件为: 焙烧温度900 ℃、还原剂配比15%、焙烧时间70 min; 粉矿焙烧的最佳工艺条件为: 焙烧温度800 ℃、还原剂配比15%、焙烧时间60 min; 内配炭球团矿焙烧最佳工艺条件为: 焙烧温度850 ℃、还原剂配比15%、焙烧时间50 min。在最优条件下得到的焙烧料用硫酸浸出,不同焙烧物料各自的还原率与浸出率相差不大,粒矿可以保持在92%以上,粉矿和内配炭球团都可以达到95%左右,接近96.52%的理论还原率。     

细菌在矿山酸性水形成和治理中的作用

矿山酸性废水是由于硫化矿物氧化而引起的污染问题，细菌加快了氧化反应的速度，在酸性水形成中起主要作用。由于氧化铁硫杆菌在Ｆｅ￣（２＋）氧化成Ｆｅ￣（３＋）时起催化作用，所以在酸性水处理中可利用细菌氧化代替空气氧化，再用ＣａＣＯ＿３使金属离子沉淀，从而降低了废水处理成本。     

硫酸直接浸出贫锰矿制备化学二氧化锰

本对贫锰矿采用硫酸直接浸出制备化学二氧化锰作了研究，对制备工艺的各工序试验结果进行了论述。结果表明，以含锰３０％左右的软锰矿为原料，可获得质量稳定的ｒ－型化学二氧化锰，锰利用率高，燕可同时生产一级品的硫酸锰和碳酸锰，为开发利用贫锰矿资源提供了可行的技术途径。     

The application of wood ash as a reagent in acid mine drainage treatment

The paper deals with a possible utilisation of wood ash as a reagent in treating acid mine drainage (AMD) from opencast mining of brown coal. Wood ash samples were obtained having combusted deciduous and coniferous tree wood in a household furnace. The dominant mineral phases in wood ash are calcite, quartz, lime and periclase. The used AMD is characteristic of high contents of sulphates, iron, manganese, heavy metals and low pH. The AMD treatment process included dosing of wood ash to adjust pH values about 8.3 (a dose of 0.5 g l⁻¹) or calcium hydroxide (a dose of 0.2 g l⁻¹) for comparison. The reaction time was 20 min. Dosing of wood ash in AMD resulted in an increase of pH in solution from 3.5 to 8.3, which caused the removal of metal ions mainly by precipitation, co-precipitation and adsorption. Comparing the application of Ca(OH)₂ in AMD treatment, at an almost identical pH value the concentrations fell in both cases for Fe, Mn, As, Co, Cu, Ni, Zn, Mg, Al and Mo. Applying wood ash the drop was even more distinct in Mn, Zn and Mg. The results of sedimentation tests in an Imhoff cone confirm that the settling capacities of sludge using wood ash are significantly better than when using calcium hydroxide in acid mine drainage treatment.     

Integrating sulfidization with neutralization treatment for selective recovery of copper and zinc over iron from acid mine drainage

The most commonly used commercial process for acid mine drainage (AMD) treatment today is lime neutralization. However, it is accompanied by the treatment of produced metal hydroxide precipitate. Because of the decrease in the capacity of landfill disposal site and the increase in the price of base metals such as copper (Cu) in recent years, it is expected that not only to treat but also to recover these base metals from AMD. For the subsequent smelting process, the major issue is how to separate the Cu and zinc (Zn) over iron (Fe) from AMD as selectively as possible.In this work, we attempted to achieve this objective by modifying the present lime neutralization treatment process with sodium hydrosulfide (NaHS) sulfidization. An AMD sample generated from an abandoned copper mine located in east Japan was utilized in this study. At first, lime neutralization was applied to the AMD to find the precipitation behaviors of Cu, Zn, and Fe. Next, NaHS sulfidization as well as the integration with lime neutralization were conducted to separately precipitate Cu, Zn, and Fe from the AMD. Finally, two modified treatment approaches for selectively recovering Cu and Zn over Fe from the AMD were proposed. The results of consecutive experiments for the two proposed approaches showed that Cu, Zn, and Fe in the AMD were removed and separated into individual precipitates, and that the concentrations of each heavy metal in the final effluent were also able to meet the Japanese effluent standards.     

Acute and Chronic Toxicity of Acid Mine Drainage to the Activated Sludge Process

The combined treatment of acid mine drainage (AMD) and municipal wastewater using the activated sludge process is an innovative approach to AMD remediation. The toxicity of synthetic AMD to activated sludge was evaluated using oxygen uptake rate (OUR) inhibition tests, which showed that activated sludge can withstand high proportions of AMD (EC₅₀ 19?C52% AMD by volume). The EC₅₀ values of municipal and industrial activated sludges were significantly different (p?<?0.05), with municipal sludges exhibiting higher tolerance to AMD. Although the EC₅₀ values for heterotrophic and nitrifying activated sludges were not statistically significantly different, the EC₅₀ values for heterotrophic bacteria were generally higher. Laboratory-based sequencing batch reactors were used to examine the treatability of AMD. Increased concentrations of COD and suspended solids, associated with turbidity and poor floc morphology, were observed in the final effluent after extended AMD loading. Protozoan community structure changed during the AMD loading period, and overall abundance tended to decrease over time. OUR decreased in the AMD-loaded reactors, particularly in the reactor receiving the highest AMD load, indicating reduced biomass activity over the acclimatization period. Results from OUR inhibition tests on the acclimatized activated sludge indicated that over a relatively short timescale (21?days), the activated sludge microbial community can adapt to AMD sufficiently so that shock loads of metals and acidity do not significantly inhibit OUR. These preliminary studies indicate that it is possible to treat AMD successfully in admixture with municipal wastewater using the activated sludge process.     

电解二氧化锰制备技术的研究进展

介绍了电解二氧化锰制备技术的发展和现状,对电解二氧化锰的生产工艺、掺杂改性、阳极材料等方面进行了详细的评述,并展望了电解二氧化锰工业的发展趋势.     

某地菱锰矿生产电解二氧化锰试验研究

针对某地菱锰矿的特点,确定采用浸出—净化—电解—成品处理的工艺流程制备电解二氧化锰。各工序锰的直收率分别为:97.61%、98.42%、99.28%、99.62%,锰的总收率为95.01%。所得电解二氧化锰产品MnO2含量≥92%,符合出口产品及日本等国某些厂家的技术要求。     

Evaluation of Airborne Thermal Infrared Imagery for Locating Mine Drainage Sites in the Lower Kettle Creek and Cooks Run Basins,Pennsylvania, USA

Abstract.  High-resolution airborne thermal infrared (TIR) imagery data were collected over 90.6 km² (35 mi²) of remote and rugged terrain in the Kettle Creek and Cooks Run Basins, tributaries of the West Branch of the Susquehanna River in north-central Pennsylvania. The purpose of this investigation was to evaluate the effectiveness of TIR for identifying sources of acid mine drainage (AMD) associated with abandoned coal mines. Coal mining from the late 1800s resulted in many AMD sources from abandoned mines in the area. However, very little detailed mine information was available, particularly on the source locations of AMD sites. Potential AMD sources were extracted from airborne TIR data employing custom image processing algorithms and GIS data analysis. Based on field reconnaissance of 103 TIR anomalies, 53 sites (51%) were classified as AMD. The AMD sources had low pH (<4) and elevated concentrations of iron and aluminum. Of the 53 sites, approximately 26 sites could be correlated with sites previously documented as AMD. The other 27 mine discharges identified in the TIR data were previously undocumented. This paper presents a summary of the procedures used to process the TIR data and extract potential mine drainage sites, methods used for field reconnaissance and verification of TIR data, and a brief summary of water-quality data.