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1.
北京有色金属研究总院稀土研究所(原稀土研究室)成立于1958年,是中国最早从事稀土工业研究和开发的单位。主要从事世界最大的稀土矿——白云鄂博和中国南方离子吸附型稀土矿的综合利用研究。研究领域包括:矿石分解、湿法冶金提取、单一稀土元素分离和提纯、金属及合金的制备和稀土新材料的研制、开发等。新材料包括:稀土荧光粉、稀土电光源材料、稀土贮氢材料、稀土电池材料、稀土永磁材料、稀土抛光粉和汽车尾气净化稀土催化剂及装置等。  相似文献   

2.
中国稀土资源储量巨大,但多为天然放射性核素伴生矿,放射性污染问题一直以来都是关注的焦点。随着稀土矿石的开发利用,这些放射性核素随之迁移,扩散,重新分布和富集,并随着稀土矿冶炼过程产生的三废进入到环境中,处理不当就会成为严重的环境污染问题,也会造成资源的浪费。放射性核素是核能发展中的重要元素,为了更好地利用处置放射性核素,应该清楚这些核素的迁移、分布和富集过程和规律。通过实地调研,考察和查阅大量文献,总结出几大稀土矿主流冶炼工艺过程中放射性元素的迁移分布规律和富集过程。结果表明:几大稀土矿虽然冶炼工艺不同,但其中放射性元素90%左右迁移、富集到冶炼废渣中,剩余少部分分布到废水、废气及产品中。因此,需要加大稀土矿冶炼新工艺的研究及现行工艺的技术改造,从源头解决放射性废渣的污染和堆存问题;研究开发现存的冶炼废渣中稀土、钍(铀)等有价元素回收利用工艺,实现废渣减量化、资源化和无害化。  相似文献   

3.
北京有色金属研究总院稀土研究所(原稀土研究室)成立于1958年,是中国最早从事稀土工业研究和开发的单位。主要从事世界最大的稀土矿——白云鄂博和中国南方离子吸附型稀土矿的综合利用研究。研究领域包括:矿石分解、湿法冶金提取、单一稀土元素分  相似文献   

4.
风化壳淋积型稀土矿是中重稀土的主要来源,它的开发一直受到稀土工业的极大关注。评述了风化壳淋积型稀土矿的成矿原因、矿床特征、稀土矿物在矿体垂直剖面中的组成和分布,以及矿石含水的多样性、酸碱缓冲性、吸附离子的稳定性和吸附离子的可交换性等理化性质。阐述了稀土离子在风化体系中的迁移富集规律和所形成的稀土配分特征。介绍了池浸、堆浸和原地浸出三代浸取工艺演化过程的科技进步,探讨了稀土浸出机制及浸出过程的强化,比较了几种浸取剂的浸取效果,简述了前两代工艺留下的采矿区和堆场区的植被恢复与土壤修复。结合原地浸出工艺的生产实际,提出了今后开发风化壳淋积型稀土矿的发展方向。  相似文献   

5.
稀土元素的性质极相近,在稀土矿物中一般有15种左右的稀土元素共生,分离提纯难度大,化工材料消耗高。中国稀土工作者根据稀土资源的特点,开发了一系列具有原创性、处于世界领先地位的稀土分离提纯技术,成就了中国稀土生产大国的国际地位。本文梳理了工业上应用的主要稀土萃取分离工艺技术特点、优缺点及适用性,其中,碳酸氢镁皂化萃取分离提纯稀土技术将镁盐废水及CO_2气体循环利用,不但从源头解决了稀土分离过程中氨氮、高盐废水污染难题,而且大幅降低生产成本,适用于P507, P204酸性磷类萃取剂在硫酸体系、盐酸体系中萃取分离稀土元素,具有良好的应用前景。进一步介绍了稀土分离提纯新方法、新技术研究进展;针对高端应用对稀土纯度等要求不断提高,以及环境治理方面面临的严峻压力和挑战,提出了稀土分离提纯领域的重点研究发展方向。  相似文献   

6.
中国是世界上稀土资源最丰富的国家,稀土工业为中国国民经济和国防建设做了重要贡献,同时也造成了巨大的环境污染。池浸、堆浸工艺是早期一代、二代浸矿工艺,本文分析离子型稀土矿池浸堆浸浸矿原理与工艺。对池浸堆浸稀土矿带来的主要污染及其污染途径进行分析,研究了废弃池浸堆浸稀土矿修复影响因素,同时提出废弃池浸堆浸稀土矿治理修复方法和主要发展方向,为后续废弃池浸堆浸稀土矿区土壤修复提供理论支持。  相似文献   

7.
离子吸附型稀土矿富含中重稀土元素,是世界罕见的稀土战略资源。针对工业普遍采用的硫酸铵浸出离子吸附型稀土矿引发的氨氮污染问题,前期研究工作提出采用镁盐代替硫酸铵作为新型浸取剂。本文就镁在土壤中的形态、作用及其有效性指标进行了综合论述,对镁盐浸出离子吸附型稀土矿的环境影响进行了分析,并提出了镁盐绿色浸取的发展方向。  相似文献   

8.
贵州织金含稀土低品位磷矿综合利用研究   总被引:2,自引:0,他引:2  
贵州织金低品位磷稀土矿:磷含量13.10%~2139%;稀土含量0.070%~0.104%,储量巨大.为探索综合利用这部分含稀土磷矿资源的途径,对其矿石特征、物相组成、化学成份和分离富集工艺进行了系统地研究,并做了实验室制备稀土钙镁磷肥的实验,所得产品磷含量15.11%~17.58%、稀土含0.0837%~0.0971%.  相似文献   

9.
我国现行主要稀土矿分解流程的经济技术指标分析   总被引:3,自引:1,他引:3  
对我国主要稀土矿分解方式进行了阐述,着重讨论了离子吸附型稀土矿、氟碳铈矿和包头白云鄂博矿的典型前处理方式的经济技术指标,对目前最常用前处理方法的投资、生产单耗、成本进行了统计和分析。离子吸附型稀土矿赋存状态奇特,富含高价值中重稀土,但品位低、分布广,多以离子交换的方式开采,环境保护面临的突出问题是植被恢复和废水达标排放;北方矿以轻稀土为主,价值相对较低,原矿品位高,分布集中,露天开采后多以重、磁、浮选工艺选出精矿,然后用煅烧和酸浸结合的工艺进行冶炼,废水和废气以及废渣是环境保护的主题。这些不同稀土矿前处理工艺的特点、发展历史以生产消耗等情况,既可作为稀土生产的投资参考,也可作为稀土企业挖潜改造、提高生产管理水平和环境保护水平的重要依据。  相似文献   

10.
目前,云南已形成了以离子吸附型稀土矿为主,砂矿型、伴生型、沉积型稀土矿为辅的稀土矿床分布格局。95%以上离子吸附型稀土矿分布于北纬26°以南腾冲-盈江-陇川和临沧-勐海-带岩浆岩分布区,成矿母岩以燕山期和喜马拉雅期的二长花岗岩为主;砂矿型稀土矿主要分布于勐海与金平-带山间盆地;伴生型稀土矿主要产于滇中地区沉积磷块岩矿床和铁氧化物-铜-金型(IOCG)铁铜矿床。腾冲花岗岩带与临沧花岗岩带La,Y异常分布区是寻找离子吸附型稀土矿最有利区域,特别是已发现矿床(点)外围区域;滇中-滇东北地区沉积磷块岩矿床、IOCG型铁铜矿床伴生的稀土资源潜力巨大,今后开采过程中应注意对稀土元素综合利用,同时应注意矿床开采后的尾砂、废弃物是否有稀土元素富集;滇东北宣威组粘土岩分布区具有与贵州赫章-威宁地区沉积型稀土多金属矿相似的成矿条件,其稀土找矿潜力巨大,沉积型稀土多金属矿有望成为中国三稀矿产资源新的来源。在今后地质工作中应加强矿床成矿规律、选冶工艺方面的研究,完善与健全矿床评价体系。  相似文献   

11.
Ion-exchangers are found not only in water purification processes, the original major application, but also in analytical chemistry for the separation and isolation of elements, hydrometallurgy, inorganic chemistry and biochemistry, in food technology, and of course in many specialized fields related to the utilization of atomic energy. The use of organic ion-exchangers is limited by virtue of their limited stability under harsh conditions, whereas inorganic ion-exchangers possess important properties, which make them very useful for chemical separation and purification in intense radiation fields. The availability of short-lived radionuclides from radionuclide generators provides an inexpensive and convenient alternative to in-house radioisotope production facilities such as accelerators and cyclotrons. Due to their simplicity of operation, chromatographic based generators have been the method of choice, although generators based on solvent extraction and on volatization and sublimation have also been developed, and are routinely used. In this paper use of inorganic ion-exchangers for the development of radionuclide generators for the decade 1993–2002 has been compiled.  相似文献   

12.
Ion-exchangers are found not only in water purification processes, the original major application, but also in analytical chemistry for the separation and isolation of elements, hydrometallurgy, inorganic chemistry and biochemistry, in food technology, and of course in many specialized fields related to the utilization of atomic energy. The use of organic ion-exchangers is limited by virtue of their limited stability under harsh conditions, whereas inorganic ion-exchangers possess important properties, which make them very useful for chemical separation and purification in intense radiation fields. The availability of short-lived radionuclides from radionuclide generators provides an inexpensive and convenient alternative to in-house radioisotope production facilities such as accelerators and cyclotrons. Due to their simplicity of operation, chromatographic based generators have been the method of choice, although generators based on solvent extraction and on volatization and sublimation have also been developed, and are routinely used. In this paper use of inorganic ion-exchangers for the development of radionuclide generators for the decade 1993–2002 has been compiled.  相似文献   

13.
评述了近五年来(2014~2018)我国近红外光谱分析技术的研究与应用进展,内容涉及方法研究、软硬件研发、应用特点和趋势等方面,并对今后我国近红外光谱技术的发展方向进行了展望。引用文献97篇。  相似文献   

14.
Three chiral compounds were successfully separated in a short time with two enantiomer separation models on packed-capillary electrochromatography (CEC). (i) 75 μm I.D. capillaries were packed with 5 μm β-cyclodextrin (βCD) chiral stationary phase (CSP). Effects of voltage, pH and concentration of organic modifier on electroosmotic flow (EOF) and chiral separations were investigated systematically. Enantiomers of a neutral compound (benzoin) and a neutral drug (mephenytoin) were separated within a short time with high efficiency. Efficiency of 32 000 theoretical plates per meter and resolution (R8) of 1.42 were achieved for enantiomers of benzoin using a βCD packed column with 6.2crn packed length. Efficiency of 45 000 theoretical plates per meter andR8 of 3.40 were obtained for enantiomers of mephenytoin. Especially, the enantiomer separation of mephenytion was performed in just 3.4 min with R8 of 2.60. (ii) 75 μm I.D. capillary was packed with octadecylsilica particles (ODs). Chiral separation of a basic drug, propranolol, was studied with chiral agent, via addition of the dimethyl-β-cyclodextrin (DM β-CD) directly into the mobile phase on this column. Baseline separation and efficiency of 81 000 theoretical plates per meter were achieved for propranolol. Project supported by the Natural Science Foundation of Liaoning Province, China, the National Natural Science Foundation of China (Grant No.29875030), and the Excellent Young Scientist Award from the National Natural Science Foundation of China. (Grant No.29725512).  相似文献   

15.
Abstract

In centrifugal partition chromatography (CPC) of rare earth metal ions (RECl3) by the use of di(2-ethyl-hexyl)phosphate (D2EHPA) as “separator” in the stationary phase, effects of number of microcells and stationary solvent were investigated for improving separation. By increasing the number of microcells from 1200 (3 cartridges) to 2400 (6 cartridges), the peak resolution value (R) for the separation of PrCl3 versus NdCl3 was improved from 0.37 to 0.62. Heavier RE ions (ErCl3 and YbCl3) was able to separate almost completely by using CHCl3 as stationary solvent. This result suggests that by adjusting these two factors, in addition to adjusting [HC1] in the mobile phase (previously reported), almost whole series of adjacent couples of RE ions will be effectively separated by CPC with acidic D2EHPA. In contrast, neutral tri-n-butyl phosphate (TBP) was found to be a poor separator.  相似文献   

16.
Initially studied in the frame of the first French act on radioactive waste management (December 1991), the pyrotechnology is currently assessed by the Nuclear Energy Direction of the Commissariat à l’Energie Atomique (CEA) within the succeeding act (June 2006) as a potential alternative to hydrometallurgy for the reprocessing of targets or dedicated fuels (coming from accelerator-driven systems or ADS) considered for the minor actinides transmutation.The R&D program is mainly focused on the evaluation of the fluoride melts as interesting media for operating separation between the actinides and the fission products. Two separation techniques are currently evaluated; the first one uses the liquid-liquid extraction technique between molten fluoride and liquid metal at high temperature, the second one is based on an electrolytic separation in a molten fluoride melt. Both are promising in terms of separation efficiency. This paper gives an overview of the current studies and presents the last main experimental results.  相似文献   

17.
基于N+离子的飞行时间质谱, 研究了N2+2离子在线偏振和圆偏振强飞秒激光场中(45 fs, 5×1015-1×1016 W·cm-2, 800 nm)的解离. 通过对N+离子质谱和平动能的分析发现, N2+2离子在线偏振光和圆偏振光作用下具有不同的解离方式. 在线偏振光下, N2分子在平衡核间距RE处发生次序双电离生成N2+2离子, N2+2离子解离所释放的能量能够用单光子跃迁模型来解释. 而在圆偏振光下, N2分子首先电离生成N+2离子, N+2离子在核间距增大到临界核间距RC(>RE)时, 进一步被电离从而发生解离, 此时解离所释放的能量可以用库仑推斥模型来解释.  相似文献   

18.
Solvent extraction (SX) has come to be one of the most important separation processes in hydrometallurgy. Phosphorus-based extractants have proved to be of particular importance, especially for the separation of cobalt from nickel. However it was not until the dialkyl phosphinic acid reagent, CYANEX 272, and its dithio analogue CYANEX 301, became available that liquors containing very low Co:Ni ratios of at least 1:40 to even >1:100 could be treated. This has opened the way to the direct application of SX for the separation of Co from Ni in liquors derived from the leaching of nickel mattes from the smelting of nickel sulphide ores and from the pressure acid leaching of nickel laterite ores. This paper describes the development of the range of Cytec extractants and, in particular, discusses the development of their application for the separation of cobalt from nickel. Examples of actual industrial operating plants will also be given and individual flowsheets discussed.  相似文献   

19.
A chiral liquid chromatographic method was developed and validated for the quantification of R‐enantiomer impurity (RE) in WCK 3023 (S‐enantiomer), a new drug substance. The separation was achieved on Chiralpak IA (amylose‐based immobilized chiral stationary phase), using a mobile phase consisting of n‐hexane–ethanol–trifluoroacetic acid (70:30:0.2, v/v/v) at a flow rate of 1.0 mL/min. The method was extensively validated for the quantification of RE in WCK 3023 and proved to be robust. For RE the detector response was linear over the concentration range of 0.11–5 μg/mL. The limit of quantitation and limit of detection for RE were 0.11 and 0.04 μg/mL respectively. Average recovery of the RE was in the range of 98.11–99.55%. The developed method was specific, sensitive, precise and accurate for quantitative determination of RE in WCK 3023. The impact of thermodynamic parameters on the chiral separation was evaluated. The method was employed for controlling the enantiomeric impurity in the lots of WCK 3023 used for pre‐clinical studies. The method was successfully applied to evaluate the possible conversion of WCK 3023 to RE in rat serum samples during pre‐clinical pharmacokinetic studies.  相似文献   

20.
To determine REE in mineral raw materials, high purity RE metals and their compounds, neutron activation analysis with extraction chromatographic REE separation has been developed. Combination of the developed RE extraction and separation procedures with subsequent -spectrometric analysis of the RE radionuclides allows to determine their content with the lower detection limit –10–5–10–8%. The relative standard deviation is 0.2–0.3.  相似文献   

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