铼的氧化动力学研究

采用热重分析(TGA)技术分别研究了粉末冶金(PM)Re和化学气相沉积(CVD)Re在空气中的氧化规律。PMRe在1000℃以上的氧化遵循与格纳的厚膜氧化规律，即氧化速率遵从抛物线定律；而在较低的温度下，CVDRe的氧化失重与时间呈直线关系。PMRe和CVDRe的氧化失重与温度的关系均符合Arrhenius公式。     

钼铼合金的结构和性能

总结了钼铼合金研究的最新进展。典型的钼铼合金成份主要有M041Re，M044.5Re和M047．5Re。钼铼合金坯锭的制备一般采用粉末冶金和真空熔炼的方法。当铼含量低于29％时，铼在钼中固溶形成体心立方结构的α相，钼的晶格常数降低。当铼含量高于29％时，形成x相和σ相。钼铼合金合金的熔点、热性能、电性能介于纯钼和纯铼之间，铼可以提高钼的再结晶温度，降低其塑脆转变温度。铼既可以提高钼的强度，也可以大大改善其塑性。钼铼合金的加工硬化率介于纯钼和纯铼之间而靠近纯钼。     

钨铼合金废料电化学溶解研究

为实现钨铼合金废料的快速、高效溶解,采用NaOH碱性体系下电化学溶解W-2 5 Re合金边角料。结果表明:当槽电压2.5 V、NaOH浓度100 g/L、电解温度30～40℃、电溶10 h时,电解溶液含W和Re浓度分别达到46.4和15.4 g/L,此时W和Re的溶出率分别为99.78%和99.35%,阳极电流效率达到98.80%,电溶能耗为2.29 kWh/kg。电溶后阳极经SEM表征,其表面呈现丘陵形貌,EDS分析表明,电溶前后阳极的W/Re质量百分比基本不变,W溶出速率约为Re的3倍。     

处理钼精矿时附带提取铼

钼精矿是提取铼的主要原料.精矿中的铼含量(决定于矿床)为10~(-3)%～10~(-4)%.原苏联处理的钼精矿与中矿含铼较富(0.2～0.7kg Re/t精矿). 氧化焙烧是处理钼精矿的主要方法.国外氧化焙烧主要在多层焙烧炉内进行,只有某些小企业在管状回转炉内进行.原苏联多层炉仅用于某些所得焙砂含硫不大于0.2%的     

W-5%Re/W-26%Re钨铼偶丝氧化行为

为了解钨铼热电偶丝在空气中的氧化过程、氧化产物成分、氧化膜生长情况,进行了DSC/TG、XRD、SEM等实验.通过填充惰性物质、脱氧、造氢、密封等实体化技术对钨铼热电偶进行了防氧化保护,利用SEM观察了保护后的钨铼偶丝的形貌.结果表明:在空气中,钨铼偶丝高温氧化产物主要为WO3;W-5%Re偶丝873℃时已经可以观察到氧化,W-26%Re的氧化温度可低至681℃;钨铼偶丝氧化层开裂并呈放射状生长,不能形成保护性氧化膜;经防护后的钨铼偶丝断面保持完整,未出现明显氧化膜.     

浅议氧化焙烧辉钼精矿过程中铼的逸出率

铼是一种稀有分散金属,在自然界中没有单独的矿床,在地壳中含量很少,主要分散在辉钼矿、铜铝矿、班铜矿中。目前,辉钼精矿是铼的主要来源。我国辉钼精矿含铢为0.0017—0.003％,铼呈ReS_2和MoS_2类质同晶伴生于辉铝矿中。在氧化焙烧辉钼矿过程中,硫化钼被氧化生成钼的氧化物,同时铼的硫化物被氧化生成易挥发的Re_2O_7进入烟气中。因为Re_2O_7易溶于水,因此可用     

富铼渣中铼浸出试验

针对富铼渣中成分多、金属赋存状态复杂的特点,采用控电位氧化浸出方法对富铼渣中的铼进行浸出试验,通过单因素试验确定了下述最优条件：氧化浸出电位700~750 mV、硫酸质量浓度15%、浸出温度70 ℃、浸出时间60 min,在此条件下铼浸出率为98.612%,其他组分浸出率均高于90%。     

改进钼精矿中铼的回收

为改进钼精矿中铼的加收，美国矿务局戈了一套由压力浸出、溶剂萃取和离子交换组成的完整工艺。工业上，铼是从硫化钼焙烧成氧化钼过程中所排放的气体中进行回收的。因该工艺效率低，所以３０－４０％的铼损失掉，而且需要大面积洗气设备才能回收气体ＳＯ２。美国矿务局研究人员指出，当硫化钼转变成氧化钼的反应在温度为２００－２１５℃，氧过压为２００－３０ｌｂ／ｉｎ＾２，反应时间为３－４ｈ条件下，铼的可溶率达９９．９％以     

高铼酸盐——氨氯吡咪盐酸盐萃取光度法测定铼

含铼（０－２０μｇ）的高铼酸盐与氨氯吡脒盐酸盐缔合，在ＰＨ４用４－甲基－２－－戊酮苯取，在波长３６２ｎｍ处测定铼。１０μｇＲｅＯ４重复测定７次的相对标准偏差为１．５％，ＰＨ和杂质离子影响测定，但仅ＣｌＯ４、Ｉ、ＩＯ４严重干扰分析。本方法适用于测定氧化铝、碳催化剂中的铼。     

钨铼热电偶的研究,开发及应用

简述了钨铼热电偶的特点、消耗型钨铼热电偶的发展及日本对国产钨铼热电偶的检定结果。探讨了钨铼合金的高温氧化行为，实体型抗氧化钨铼热电偶的研制、应用及存在的问题。结果表明：用抗氧化钨铁热电偶部分取代S型热电偶，用于工业过程温度检测是可行的。     

熔炼次数对M17返回料合金成分、组织和性能的影响

实验结果表明,M17铸造高温合金(%:0.16C、8.79Cr、5.79A1、4.93Ti、3.29Mo、15.20Co、0.78V、0.015B、0.073Zr、0.002S、0.001P、0.001 1O、0.001 0N)经25 kg真空感应炉返回重熔后,Si含量随重熔次数的增加而略有增加,合金中主要元素和其它杂质元素S、P、H的含量变化不大,而氧、氮略有增加;合金中初生碳化物由新合金中的草书体逐渐向返回合金块状转变,初生碳化物的遗传性堵塞合金凝固时的补缩通道,使返回料合金的疏松倾向增大,高温塑性下降较大。     

China's Major Non-ferrous Metals Imports & Exports

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Zinc Production by Province in 2014

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80% of Chinese Firms Purchasing Overseas Mines Ended up in the Red

<正>Minmetals Resources acquired the world’s largest copper mine under construction for USD5.85 billion.One after another,listed companies Jien Nickle,China Molybdenum and Chihong Zinc and Germanium raised money to get involved in overseas mining projects…SOEs and private enterprises are engaged in a frenzy of overseas mine purchasing.A reporter with Economic     

Copper Processing Profit Dropped Sharply,Copper Consumption Will Face Impact in the Second Half of the Year

正Judging from China’s copper consumption field,the biggest consumption unit is electric power,which accounts for 47%of total consumption;it is followed by light industry sector,including household electrical appliance,machinery,durable goods and hardware etc,which accounts for 22%of total consumption;followed by transportation field,     

Central Geological Prospecting Fund Newly Added 16.47 Million Tonnes of Bauxite in 2013

正In 2013,the Central Geological Prospecting Fund(CGPF)Project newly discovered 15 ore fields,including 3 large above ore fields,and 5medium sized ore fields.The reporter learned from the recently published"Annual Report of Central Geological Prospecting Fund Project(2013)"that,from 2006 to 2013 the CGPF     

Manufacturers of Copper Tube for Central Air Conditioner Use Face Mounting Pressure in the Final Quarter of the Year

正This year,the investment growth rate of real estate industry continued to slow down,sold area of commercial housing also dropped significantly,which brought huge pressure to the domestic air conditioning manufactures.In the first half of the year,by relying on high growth in national financial expenditure,along with investment in public infrastructure     

Xinjiang Ranks No.1 in Production of Primary Aluminum in China

正Kang Yi,Honorary Chairman of China Nonferrous Metals Industry Association,said recently at the Forum on Development of the Non-ferrous Metals Industry in Central and Western China held in Zhengzhou that,as more and more electrolytic aluminum factories in Xinjiang came into operation,the electrolytic aluminum output of Xinjiang had reached2,275,000 tons in the first 7 months this year,     

Shenhuo Coal Industry and Electricity Power Completed800,000 t/a Aluminum Project in Xinjiang

正"Xinjiang project has been completed according to schedule,but total completion and total start of production are two different concepts,after completion it still needs a gradual process of reaching production target."On the morning of November 3,Shenhuo Coal Industry and Electricity Power told investors the above statement on the investor interaction platform.     

Guangdong Metal Transaction Center has Become the Second Largest Precious Metal Transaction Platform Nationwide

正The reporter learned from Guangdong Province Precious Metal Transaction Center that in 2013the Center maintained healthy development momentum,and had become the second largest precious metal transaction platform in China in terms of market size;currently Guangdong is quickening steps of financial innovation for the Center,aiming to build a transaction center with international core competitiveness.