发射光谱法测定锇中贵金属杂质

锇在地球上含量比稀有金属还要低。文献曾报道了用化学光谱法进行测定[1 ] ,但此方法繁琐 ,耗时颇长。锇是一种高熔点元素 ,同其它铂族金属一样可以制成海绵状金属 ,可采用粉末试样光谱分析法进行分析。不同之处是 ,锇在空气中常温下就能被氧化成有毒氧化物四氧化锇 ;在加热到 80 0℃时 ,便迅速氧化成剧毒气体 ,达到一定浓度便会刺激眼睛 ,引起视力模糊 ,甚至失明。因此 ,采用一种通风良好、样品和标样密封保存、摄谱时加置安全防护罩的发射光谱法测定锇中杂质元素的分析方法。操作简便 ,优于常用方法检出限的分析方法。1　实验部分1 1　仪…     

溶剂浮选-偏最小二乘回归光度法测定地质样品中痕量贵金属元素

研究了贵金属Ru、Rh、Pd、Au-SnCL_2-RB体系及缔和物溶剂浮选的条件,采用偏最小二乘回归法对重叠光谱进行解析及数据处理.对地质样品中Ri、Rh、Pd、Au同时测定,相对误差小于11.1%;标准偏差为0.0062～00.19.     

电气线路火灾中铜导线一次短路与二次短路的显微组织特征

对电气线路火灾中铜导线的一次短路与二次短路的显微组织特性进行了对比分析,利用二者之间微结构开头上的差异来分析鉴定火灾的起因,为公安消防部门侦破火灾案件提供了有利的科学证据,可使案件侦破率及破案速度大大提高。因而,将此项工作加以推广有十分重要的意义。与金相显微镜比较,用电镜进行观察分析具有放大倍数连续调节范围大,景深大,分辨率高,同时具有图象更清晰,立体感更明显的特点。     

贵金属纳米材料的研究进展

上世纪80年代初,科学家们就发现,当某些材料的尺寸处于介观状态时,其宏观性质发生了巨大的改变,而且当材料的尺寸降至纳米范围内时,许多新奇的性能是传统的理论所无法预知的.因而,纳米材料已经成为最具发展潜力的研究热点之一.纳米尺度的贵金属材料,因其突出的催化性质、电性质、磁性质和光学性质,已经成为纳米科技领域中最富有活力的分支学科.本文介绍了贵金属纳米材料的合成方法及其优良性能,并对其未来发展作一展望.     

电感耦合等离子体原子发射光谱法及电感耦合等离子体质谱法在二次资源分析中的应用进展

综述了2005-2012年间国内利用电感耦合等离子体原子发射光谱法(ICP-AES)和电感耦合等离子体质谱法(ICP-MS)测定二次资源中有关元素、特别是重金属元素的分析的最新进展,从样品前处理方法、仪器测定条件优化、技术联用等方面阐述了上述两种方法在二次资源重金属分析中的应用(引用文献40篇)。     

佛山市南海邦普镍钴技术公司在二次电池回收、再利用与资源再生方面的进展

中国是全球最大的电池生产和消费大国，其一次电池的产量已远超过美国和日本，位居全球第一，且二次电池产量也仅居日本和韩国之后，位居世界第三。2004年中国的电池产量超过280亿只（占全球电池供应量的25％），其中锂电池为9．4亿只、镍镉电池为10亿只、镍氢电池为8亿只、碱性电池为220亿只；2005年中国的的电池产量超过230亿只，继续位居全球第一，其中一次电池和二次电池的产量分别为190亿只和37亿只（即锂离子电池为22亿只、镉镍电池10亿只和氢镍电池5亿只）。由于欧盟委员会颁布了电池指令（2002／525／EC），生产者责任制的逐步实施，西方国家的电池生产企业正面临日趋严格的环保压力，迫使美、日等国的电池产业向中国等欠发达国家转移，在中国的长三角、环渤海湾或珠三角地区独资设厂、控股或参股中国电池企业。仅珠三角地区目前就有数十家产值过亿元的知名电池企业，如深圳比亚迪股份公司、深圳比克电池公司、深圳雄韬电源科技公司、深圳今星光实业公司、深圳豪鹏科技公司、东莞市迈科科技公司、金霸王（中国）有限公司、东莞高力电池公司、广东汤浅蓄电池公司、日本TDK电池、江门市三七电池公司、佛山市南海新力电池公司，此外，还有很多未进入电源行业统计数据的小型二次电池企业。据估计，大型电池企业的废品率一般在1％～3％、极片生产过程中的边角料1％～2％，而小型企业的残次品率更高。以2005年为例，中国二次电池行业的废品在1亿只左右，约重3000吨，按钴镍含量20％计算，其价值在3亿元左右，但对于电池企业而言，建立专门的废品处理工厂是不经济的，而一般采用定期挂牌拍卖方式处理，然而采用传统的选冶工艺，难以满足废旧电池资源化循环利用在经济性、生态性、高效性、综合性等方面的基本要求。此外，随着手机型号的变更，大量库存电池也需要物尽其用。 佛山市南海邦谱镍钴技术有限公司是创建于2003年的专业从事各种废旧镍氢、镍镉、锂离子二次电池等废镍、废钴回收与处理的再生资源技术企业，总占地面积达50000平方米，固定资产1000万，各类高精加工和自主创新设备（专利号：200620059829．X）约100余套，经过近4年的发展，现已发展成中国最大的库存二次电池再利用、废旧二次电池拆解及其再资源化的废镍钴原料供应商之一。公司现有员工约100余人，其中专职技术人员20余名，分别来自清华大学、中南大学等知名院校。公司创建伊始就严格按照ISO9001：2000、ISO14001：2004的要求进行生产和管理。凭借专业化、有序化的生产管理，目前电池月回收量达1000万只，废镍、废钴月处理利用量达300吨，2006年产值突破12亿元。自2007年1月以来，佛山市南海邦普镍钴公司与清华大学核研院正式建立校企战略合作伙伴关系，共同开发和改进废旧镍氢、锂离子电池拆解技术，拟建一座年处理3000吨含20％镍的电池废料中试基地；并在清华大学核研院设立“清华核研院-镍钴技术奖学金”，奖励从事循环经济和环保事业的优秀人才。目前已成功设计了废旧镍氢电池回收再利用的成套技术和生产设备，且在锂离子聚合物回收资源再生及无害化处理工艺方面已获得重大突破，并投资1000万元建设邦普镍钻技术研发中心，将拥有原子吸收光谱仪、紫外可见光分光光度计、X射线粉体衍射仪、激光粒度分析仪和全谱直读等离子体发射光谱仪等先进检测仪器。2007年4月19日，国家科技部社发司资环处、中国有色金属工业协会再生金属分会、广东省科技厅、佛山市科技局等各级领导曾莅临公司视察工作，对公司的未来战略发展提出了殷切希望。 本文拟以废旧二次电池的拆解与回收处理为例，着重介绍佛山市南海邦普镍钴公司在库存电池的再利用、废旧电池的拆解技术等领域的研究进展。     

二次离子质谱生物成像

二次离子质谱作为目前空间分辨率最高的质谱成像技术,以其免标记、高灵敏、多组分检测优势和亚微米级高空间分辨成像优势为诸多生命科学问题的研究提供了全新的分析手段,在基础细胞生物学、组织生理病理学、生物医药与临床医学等领域的研究中得到了广泛应用.本文综述了二次离子质谱在生物组织、细胞、仿生生物膜等体系中的质谱成像研究进展.     

高分子负载贵金属类催化剂及其在有机反应中的最新应用

高分子负载金属催化剂与传统的均相催化剂相比,具有较高的催化活性、立体选择性、较好的稳定性和重复使用性能,并且后处理简单,在反应完成后可方便地借助固-液分离方法将高分子催化剂与反应体系中其他组分分离、再生和重复使用,可降低成本和减少环境污染。本文综述了近五年来高分子负载贵金属类催化剂在有机反应中的最新应用,根据金属不同将其分为钌、钯、银、金四大类,并分类介绍了其在不同固相反应中的应用。本文介绍的负载贵金属类催化剂中的负载物均为不溶性聚合物,但不包括二氧化硅、可溶性聚合物和树枝状大分子等。     

微波消解方法在贵金属分析中的应用

贵金属包括铂族元素和金银共8种。铂族金属对酸的化学稳定性比所有其它金属都高,其中钌和锇、铑、铱对酸的化学稳定性特别高,不仅不溶于普通酸,甚至也不溶于王水,钯和铂能溶于王水。钯是铂系元素中最活泼的一个,可溶于浓硝酸和热硫酸。金一般只溶于王水。银是贵金属中最活泼的,能溶于硝酸和热的浓硫酸,但因生成氯化银沉淀而不溶王水。由于贵金属的溶解困难,在贵金属的分析中,样品制备显得尤为重要,因为制备过程中的掺杂问题,许多试验者选择固体粉末直接检测方法,使贵金属的检测准确度和灵活性差,并因基体效应增加了基体匹配的难度。     

二次电池用局部高浓度电解质的研究进展与展望

电解质作为二次电池离子传导的重要介质,对于提升二次电池循环稳定性能、安全性能等方面起着至关重要的作用.局部高浓度电解质是指在高浓度电解质中加入"稀释剂",形成盐的局部高浓度状态,既能兼具高浓度电解质的优异特性,又具有低成本和优良润湿性的特点,应用前景非常广阔.近几年,局部高浓度电解质在阻燃锂金属电池、高电压锂电池、低温锂电池、锂硫电池和钠电池等多方面应用广泛,且展现出非常好的使用效果.本综述重点从局部高浓度电解质的功能性应用角度出发,详细阐述了局部高浓度电解质的类型、制备、作用机理及其在不同二次电池中的功能性应用进展和主要研究现状,文末还对局部高浓度电解质的未来可能发展趋势进行了分析与展望.     

Matrix elimination method for the determination of precious metals in ores using electrothermal atomic absorption spectrometry

Poly(N-(hydroxymethyl)methacrylamide)-1-allyl-2-thiourea) hydrogels, poly(NHMMA-ATU), were synthesized by gamma radiation using ⁶⁰Co γ source in the ternary mixture of NHMMA-ATU-H₂O. These hydrogels were used for the specific gold, silver, platinum and palladium recovery, pre-concentration and matrix elimination from the solutions containing trace amounts of precious metal ions. Elimination of inorganic matrices such as different transition and heavy metal ions, and anions was performed by adjusting the solution pH to 0.5 that was the selective adsorption pH of the precious metal ions. Desorption of the precious metal ions was performed by using 0.8 M thiourea in 3 M HCl as the most efficient desorbing agent with recovery values more than 95%. In the desorption medium, thiourea effect on the atomic signal was eliminated by selecting proper pyrolysis and atomization temperatures for all precious metal ions. Precision and the accuracy of the results were improved in the graphite furnace-atomic absorption spectrometer (GFAAS) measurements by applying the developed matrix elimination method performing the adsorption at pH 0.5. Pre-concentration factors of the studied precious metal ions were found to be at least 1000-fold. Detection limits of the precious metal ions were found to be less than 10 ng L⁻¹ of the all studied precious metal ions by using the proposed pre-concentration method. Determination of trace levels of the precious metals in the sea-water, anode slime, geological samples and photographic fixer solutions were performed using GFAAS clearly after applying the adsorption-desorption cycle onto the poly(NHMMA-UTU) hydrogels.     

Sample digestion methods for the determination of traces of precious metals by spectrometric techniques.

Recent advances in digestion methods used in the analysis of precious metal samples by spectrometric techniques are reviewed. The applicability of a fire assay, a wet acid treatment, chlorination and alkaline oxidizing fusion to a quantitative recovery of metals from various materials is discussed. Data on the precious metal contents obtained by using particular digestion methods as well as UV-VIS spectrophotometry, atomic absorption spectrometry, atomic emission spectrometry and inductively coupled plasma mass spectrometry in the examination of various samples are tabulated.     

Determination of some precious metals by neutron activation analysis

A neutron activation procedure for the determination of Ru, Pd, Os, Ir, Pt and Au in a single irradiation in silicate rocks, meteorites and sulfide ores has been developed. An alkali fusion was used to dissolve and mix 100 to 200 mg powder samples with appropriate carriers. The individual metals were separated and brought to a state of high radiochemical purity by distillation, ion exchange and solvent extraction techniques. Precious metal activities were counted by both γ and β-methods. The procedure was evaluated by replicate analyses of the granite and diabase rock standards, G-1 and W-1 and a Cu−Ni sulfide matte which had previously been analysed by emission spectrographic and spectrophotometric methods. The results were compared with previously published data. A major discrepancy was found only for Ir in W-1.     

Selective resins,synthesis and sorption for precious metals

Resins based on vinylbenzyl chloride (VBC) and divinylbenzene (DVB) copolymer were synthesised and used for preconcentration and separation of Au, Pt and Pd from hydrochloric acid solutions. Resulted resins show functionality concentration up to 5,8 mmol/g. The acidity and interference of other ions on the resins sorption were discussed. The sorption capacities of gold, platinum and palladium from hydrochloric solutions reaches to 85, 100 and 60 mg/g and distribution coefficients achieve 50 000 value. Recovery of noble metals revealed average of 60-98% from mulitcomponent solutions.     

Paper chromatography in the separation of ions : Separation of precious metals

A study of the separation of the precious metals. Pd⁺², Pt⁺⁴, Ir⁺⁴, Rh⁺³, Ru⁺³, Os⁺⁴ and Au⁺³, by ascending paper chromatography, using different solvents and a number of complexing agents, clearly shows that microgram amounts of the elements, when present in a mixture of five, are best separated from each other in the presence of thiourea. The Rl, Rrt values and the sequences of separation are recorded in tables to show whether a good separation of a particular mixture of ions is possible.     

Circular-paper chromatography in the separation of ions : Separation of precious metals

A. circular-paper Chromatographie method for separating the precious metals Pd⁺², Pt⁺⁴, l^r+4. Rh⁺³, Ru⁺³, Os⁺⁴ and Au⁺³, using several solvent mixtures with or without complexing agents, has been studied. Mixtures of microamounts of three or four of these metals can be effectively separated into distinct circular zones within one or two hours.     

Surface modification of phosphate ion to promote photocatalytic recovery of precious metals

Photocatalytic recovery,a novel precious metal recycling technology,dedicates to solving the environmental and energy consumption problems caused by traditional technologies.The activation of molecular oxygen (O₂) is one of the most critical steps in the whole process.Herein,we regulated the different adsorption intensity of oxygen on the surface by designing phosphate (PO₄^3-) modified titanium oxide(Ti O₂).The results show that the adsorption of oxyge...     

Retention and elution of precious metals on cyano-modified solid phase microparticle sorbent

We report on a study on the retention and elution of ions of the precious metals Au, Ir, Pd, Pt, Rh and Ru, sometimes in the presence of ions of the nonprecious elements Co, Cu, Fe, Ni, Pb and Te. A commercial cyano-modified microparticle-based solid phase was used as a sorbent and hydrochloric acid in various concentrations for sample solution and elution. Only Au and Pd (in the form of their chloro complexes) were retained, and Au is found to have a much higher affinity for the sorbent compared to Pd. In addition to the affinity of the metal towards the functional groups, the retention behavior of the precious metals seems to be mainly influenced by steric factors of their respective chloro complexes. Elution with 7.5 M HCl does not require the addition of organic eluent as required in other cases. The method can separate Au or both Au and Pd, from hydrochloric acid solutions containing ions of other precious metals or nonprecious elements. The sorbent was applied to recover gold from a mineral digest containing large amounts of metals such as Fe, Pb, Te, Cu, Ni and Zn.

Electro-chromatography in the separation of ions : Part II. Separation of precious metals

An electrochromatographic study of the migration rates and sequences of the precious metals, as Pt⁺⁴, Os⁺⁴, Ir⁺⁴, Ru⁺³, Rh⁺³, Au⁺³ and Pd⁺², on paper strips, reveals that quite a large number of electrolytes effectively separate in distinct zones at least four ions present in microgram amounts in a mixture, when the voltage is maintained at 150 V for 5 hours.