闪锌矿分析

闪锌矿的主要成分是锌(67％)和硫(32％),同时伴生有有色,分散元素要求分析。本文采用阳离子树脂交换分步淋洗,对砷、硒、碲、锗、锌、铜、镉、钴、镍和铁等元素进行分离与测定。     

树脂交换分离-电感耦合等离子体质谱法测定铅锌矿中钨钼锡锗硒碲

铅锌矿常与硫化矿共生形成复合多金属矿床,其中伴生有益元素的含量对矿床的综合利用评估有重要的参考意义。在目前常用方法中,钨钼锡锗硒碲主要采用分组或单独熔矿和测试的方法,操作强度大、分析效率低,且高含量铜、铅和含量高于1μg/g的硒分别干扰钨钼和碲的测定。本文采用过氧化钠碱熔,提取后加入0. 8%柠檬酸溶液络合钨、钼、锡形成金属复合物,以8～9 g阳离子树脂交换分离高含量钠盐和铜、铅、锌、铁等主量元素,采用动能歧视模式以铼、硼为内标用电感耦合等离子体质谱仪同时测定钨钼锡锗硒碲的含量。经树脂处理后,铜铅锌铁的去除率均高于96%,在测定介质中实际浓度为0. 192 ng/mL～1. 28μg/mL,基本消除了主量元素的干扰。各待测元素工作曲线相关系数为0. 9994～0. 9999,优于阳离子树脂处理前的0. 9923～0. 9992。经标准物质验证,各元素测定相对误差为-8. 33%～7. 00%,加标回收率为94. 9%～107. 5%,相对标准偏差(RSD,n=8)小于8%。该方法在样品前处理环节将主量干扰元素从溶液体系中分离,优化了测定介质,实现了铅锌矿中多元素的准确快速测定。     

氢化原子吸收法测定矿石及地球化学样品中微量硒、碲

硒碲氢化原子吸收法测定,已见报道。文献曾连续对硒碲等元素的氢化原子吸收法的条件进行了研究。文献对原子吸收法测定硒进行了评述,提到了氢化原子吸收法测定硒的条件。文献对氢化物—无色散原子荧光法进行了详尽的研究,提出了用该法测定地质样品中>0.0001％的硒碲。本钢钢研所把氢化原子吸收法用于测定钢铁中>0.0001％的硒碲等七个元素。但对于矿石、地球化学样品中微量硒碲的氢化原子吸收法连续测定,尚未见到详细报导。作者对氢化原子吸收法连续测定硒碲的条件进行了研究。提出了用巯基棉富集硒碲与干扰元素分离,确定了最佳测定条件,拟定了分     

微量硒的碘量罗丹明B比色和碲的丁基罗丹明B比色测定

在自然界中硒与碲经常共生,因此考虑在同一份取样中进行硒与碲连测比较合理。利用砷作共沉剂、在1∶1盐酸介质中用卑磷酸盐将硒、碲还原沉淀富集,可与伴生杂质分离。此时金和汞也被定量沉淀下来。若采用焙烧法分解试样,可将大量汞挥散除去。只有金与微量硒、碲的分离,手续比较冗长。     

西南低温成矿域铊(含铊)矿床地球化学和生物成矿

西南低温热液改造矿床成矿域包括扬子地块西南缘一百多万平方公里的广大地域;东与华南褶皱系毗邻,西到云南三江地区,南至中越边境,北与四川接壤,地域广阔、矿种齐全,类型之多、规模之大、组合之复杂堪称世界低温热液改造矿床成矿域之最。最使人瞩目的就是这一地域孕育着一批大型和超大型汞、锑、砷、铅、锌等有色多金属矿床,金、银、铂、钯贵金属矿床(矿化),铊、镉、锗、硒、碲分散元素矿床和水晶、重晶石、萤石等非金属矿床。     

砷用作探途元素

许多矿床,特别是含硫化物和硫盐类的矿床,砷是一种学风组分,是化探的一种指示无素.在这些矿床中,砷常与铜、金、银、锌、钼、镐、汞、铀、锡、铅、钨、磷、锑、铋、硒、碲、铁、镍、钴、铂等伴生.多数情况下,砷是这些元素最     

无极放电灯的再生

随着化探,水质等样品的分析,不少实验室引进了无色散原子荧光仪,该仪器目前配用无极放电灯和低压汞灯两种光源。为了实现多元素的连测,一般选用前者,测定砷、锑、铋、汞、硒、碲、锡、铅、锗等元素。由于这种灯原材料不纯和制造工艺不完善,造成商品灯光源不稳,同时寿命较短。由     

电感耦合等离子体质谱法同时测定地质样品中痕量碘溴硒砷的研究：Ⅱ.土壤及沉积物标准物质分析

样品用碳酸钠和氧化锌混合熔剂半熔，热水提取，然后用强酸性阳离子交换树脂将阴离子形式存在的分析元素与溶液中大量钠、锌等阳离子分离，采用电感耦合等离子体质谱法直接同时测定溶液中的碘、溴、硒、砷。用0.07mol/L的氨水溶液清洗进样系统，有效减少了碘等元素的记忆效应和清洗时间。方法检出限（10σ，DF=100）溴、碘分别为0.15和0.028μg/g，砷、硒分别为0.04和0.004μg/g。用土壤和沉积物等地质标准物质分析验证了方法的准确度和精密度，绝大多数分析结果在标准值的允许误差范围之内。样品10次测定的RSD为0.8%～2.8%。     

气相色谱和薄层色谱法在形态分析中的应用

评述了气相色谱和薄层色谱法用于氯、溴、碘、硫、硒、碲、铬、氮、磷、砷、钒、碳、锡、铅、铁和汞１６种元素的不同形态分析的进展。这些形态包括不同价态、有机态、无机态、阳离子和阴离子态等。由于气相色谱和薄层色谱法都具有分离和检测两种功能结合的特点，因此它们是用于元素形态分析的有效和方便的方法。引用１９８０～１９９４年文献９２篇     

多金属矿床伴生稀有分散元素取样分析方法

在分布很广的岩浆期后多金属矿床中,除富集有铅、锌、铜等主要有用金属元素外,同时有多种有益伴生元素的富集,诸如金、银、铋、钴及稀有分散元素之铟、镓、锗、镉、铊及硒、碲等.在勘探利用主要矿产的同时,为合理综合利用矿产资源扩大稀有分     

多壁碳纳米管固相萃取快速检测水样中铅镉铜铁

传统的固相萃取填料应用于环境样品的重金属处理过程中,存在pH不稳定和不同极性萃取物共同萃取较为困难等方面的不足,因此寻找新型固相萃取填料显得尤为重要。本文采用多壁碳纳米管填充固相萃取柱,萃取水中金属元素铅、镉、铜和铁,采用石墨炉原子吸收光谱法测定铅和镉,电感耦合等离子体发射光谱法测定铜和铁。实验考察了多壁碳纳米管的性质、溶液pH值、洗脱溶液、样品流速以及基体效应对测定结果的影响。结果显示:溶液pH=9,1 mol/L硝酸为洗脱溶液,样品流速为2 mL/min时,外径8 nm未修饰的多壁碳纳米管有较好的萃取效率,对溶液中铅、镉、铜和铁的最大吸附容量分别为44.91、42.31、54.68和49.07 mg/g,四种元素的吸附容量均衡;钾、钠、钙、镁离子以及苯和甲苯等基质对四种金属元素的萃取影响不大。方法回收率为95.3%~99.5%,精密度(RSD,n=7)为1.2%~3.2%。本方法采用外径8 nm的多壁碳纳米管固相萃取,与传统萃取方法相比,富集效果好、回收率较高,而且操作简便、准确度高;与前人采用外径20~30 nm的多壁碳纳米管的性能相比,镉和铜的吸附容量更高,还可实现对铁的吸附,且铅、镉、铜和铁四种元素的吸附容量均衡,更适合用于检测水样中的金属元素。     

铬黑T 形成树脂分离富集极谱测试地质样品中贵金属Pt、Rh、Ru 研究

合成并研究了铬黑T 形成树脂分离富集地质标准样品中的钌、铂、铑,获得了最佳实验条件。结果表明: pH = 2. 00 的盐酸溶液作为介质、温度为293 K、流速v≤1. 0 mL·min － 1、柱高h≥10. 0 cm,铂、铑、钌吸附率均在95%以上; 在293 K,使用40 mL 的pH 2. 00 盐酸－ 3%硫脲溶液静态洗脱或以1. 0 mL·min － 1的流速进行动态洗脱,洗脱率均在95%以上。树脂对铂、铑、钌的吸附过程符合拟二级动力学模型。实验条件下的标准回收实验,回收率均＞ 95%。对地质标准样品进行了分析测定,相对误差均＜ 7%。铂、铑、钌的相对标准偏差分别是铂: 0. 852 0%和0. 325 0%; 铑: 4. 20%和 4. 89%; 钌: 1. 24%和1. 79%。铂、铑、钌的检出限分别为3. 55 × 10 － 6 μg·mL － 1、6. 23 × 10 － 7 μg· mL － 1、1. 92 × 10 － 5μg·mL － 1。该方法的准确度和精密度较高。     

Iron deposition as acidic groundwater encounters carbonates in the alluvium of Pinal Creek,Arizona, U.S.A.

In a column experiment, acidic groundwater from Pinal Creek Arizona, a Cu mining area, was eluted through a composited alluvial sample obtained from a core that had been removed from a well downgradient of the acidic groundwater. The minerals present in typical grains and flakes in the alluvium before and after the elution were determined by X-ray diffraction (XRD), scanning electron microscopy, and energy dispersive multichannel analyses (EDX). The concentrations of Fe, Ti, Mn, Si, Al, Na, Ca, K, Mg and S in these grains and flakes and in their microcrystalline surface coatings were measured by EDX.In addition to magnetite, hematite, and Fe-Ti oxides, Fe was most concentrated in micas (especially biotite-like flakes) and in the microcrystalline coatings. The measured elements in these microcrystalline coatings were primarily K, Fe, Al, and Si. The microcrystalline coatings on the mica flakes also contained Mg. The approximate l:3 Mg:Si atomic ratios (ARs)_of the biotite-life flake both before and after the elution would suggest that the Fe deposited during the elution had not substituted for Mg in these flakes. As a result of the elution, assuming no loss of Si, the averaged recorded Fe:Si AR of the microcrystalline coatings increased from (0.46 to 0.58):3.00.Iron deposition on the typical grains and flakes may relate to the presence of Fe in the particle on which it is deposited or to the presence of Fe in the microcrystalline surface coatings before elution. The data here are not sufficient for a statistical evaluation, but elution caused the following trends: (l) The Fe:Si AR increased in the (K,Fe,Al,Si)-microcrystalline surface coatings; (2) For the mica flakes, there was more than a 2-fold increase in the Fe:Si AR for the microcrystalline surface coatings of the Fe-rich biotite-like flakes but no measurable increase of the Fe:Si AR for the microcrystalline surface coatings of the muscovite-like flakes that contained 3–5 times less Fe; (3) Also for the biotite-like flakes, the increase in Fe:Si AR was greater in the flakes that had a higher Fe:Si AR; (4) The Fe deposition on the Fe-rich microcrystalline surface coatings of the feldspar was much greater than on the Fe-poor, beige quartz and feldspar grains that, prior to elution, had only CaS0₄ microcrystalline coatings; and (5) No Fe was deposited on Fe-poor grains with no microcrystalline surface coating.     

离子交换分离-石墨炉原子吸收光谱法测定高纯铟中的痕量银

银是高纯铟的常检痕量元素,由于银含量低,一般的分析方法难以达到期望的检出限。本研究样品用硝酸溶解,强酸性阳离子交换树脂分离,试液蒸发浓缩后用石墨炉原子吸收光谱法测定高纯铟中痕量银。通过溶样方法、离子交换分离条件和仪器测定条件实验,结果表明,以0.7 mol/L硝酸作为淋洗液进行分离,样品中痕量砷、铝、铁、锡及大量的铟可被分离除去;铜、镉、镁、镍、锌、铅、硅和铊不能与银分离,但对测定无影响。方法线性范围为0～50 pg,相对标准偏差(RSD,n=8)小于10%,银的检出限为0.3 pg,测定下限为0.8ng/g,比文献方法的0.02～1μg/g中最低者低2个数量级,加标回收率为93.3%～110.0%。本方法由于分离了基体铟,避免了铟对银测定的影响,兼之将试液浓缩,有效地降低了检出限,且测定时无需使用基体改进剂,成本低,灵敏度较高,适合于高纯铟中痕量银的分析。     

P350微色谱柱在线分离富集-火焰原子吸收光谱法测定矿石中痕量金

在王水介质条件下,用自行设计的微色谱柱在线分离富集系统分离富集矿石样品中的痕量金,采用火焰原子吸收光谱法进行测定。在原子吸收光谱仪吸喷溶液的流路上,用P350微色谱柱研究了金的分离富集条件,采用快速吸附和快速洗脱技术,以盐酸溶液为淋洗液,亚硫酸钠溶液为洗脱液,测定一个样品整个分离和测定过程仅需1 min,成功地克服了火焰原子吸收光谱法测定金灵敏度低的缺点。方法的相对标准偏差小于3.2%,检出限为0.078μg/g。与现行离线分离富集方法相比,建立的方法具有高效、快速、成本低廉的优点,经实际样品验证获得了较为满意的结果。     

甲基膦酸二甲庚酯(P_(350))—吸附树脂萃取色层分离连续测定矿石中铀和钍

本文选用水溶性比TBP小30倍而对钍、铀分离效率高的P_(350)为萃取色层的固定相和对有机萃取剂吸附容量大、传质速度快的新型大孔吸附树脂x-5(聚二乙烯苯)为支持体,以含15%HNO_3和15%NH_4NO_3(或7%Al(NO_3)_3)及2%酒石酸的混合液为铀、钍上柱液,采用5NHCl及0.2%NaF分别解脱钍和铀,分光光度法分别测定之。     

ICP—AES法测定镁合金中微量铜、锰、锌、铝、铁、硅

用电感耦合等离子体发射光谱（ICP—AES）法测定了镁合金中Cu、Mn、Zn、Al、Fe、Si等元素,进行了模拟基体匹配实验,消除了镁基干扰。用饱和硼酸溶液络合过量的氟离子,可准确测定溶液中微量Si元素。国家标准物质ZM3测定值与推荐值较吻合,方法检出限为0．003μg／g～0．053μg／g,相对标准偏差RSD〈4％。     

Sorptive flotation for metal ions recovery

In this study, the abstraction of nickel, copper and zinc ions from aqueous solutions has been investigated in a laboratory batch scale mode. A combined two-stage process is proposed as an alternative of the heavy metals removal from aqueous solutions. The first stage is the sorption of heavy metals onto non-living microorganisms followed by dispersed-air flotation of the loaded biomass. Three types of strains were used: Penicillium chrysogenum, Saccharomyces carlsbergensis and Streptomyces rimosus. The main parameters studied were solution pH, biomass concentration, surfactant concentration and flocculant concentration. The biomass reuse after elution was also examined. Remediation is a possible application of flotation being cost-effective and with readily available equipment and know-how. The application of this process looks promising.     

等离子体发射光谱法测定重晶石中钡铁和硅

重晶石经Ｎａ２ＣＯ３熔融,水浸取,过滤。沉淀经ＨＣｌ溶解后,用电感耦合等离子体发射光谱法同时测定主成分ＢａＳＯ４和次量成分Ｆｅ２Ｏ３以及滤液中的ＳｉＯ２,结果与部颁标准方法符合。方法精密度好,主量组分ＢａＳＯ４测定的ＲＳＤ（ｎ＝６）为０．２４％,次量组分Ｆｅ２Ｏ３和ＳｉＯ２的ＲＳＤ（ｎ＝６）分别是３．６９％和１．４５％。     

Ion-exchange fractionation of copper and zinc isotopes

Whether transition element isotopes can be fractionated at equilibrium in nature is still uncertain. Standard solutions of Cu and Zn were eluted on an anion-exchange resin, and the isotopic compositions of Cu (with respect to Zn) of the eluted fractions were measured by multiple-collector inductively coupled plasma mass spectrometry. It was found that for pure Cu solutions, the elution curves are consistent with a ⁶³Cu/⁶⁵Cu mass fractionation coefficient of 0.46‰ in 7 mol/L HCl and 0.67‰ in 3 mol/L HCl between the resin and the solution. Batch fractionation experiments confirm that equilibrium fractionation of Cu between resin and 7 mol/L HCl is ∼0.4‰ and therefore indicates that there is no need to invoke kinetic fractionation during the elution. Zn isotope fractionation is an order of magnitude smaller, with a ⁶⁶Zn/⁶⁸Zn fractionation factor of 0.02‰ in 12 mol/L HCl. Cu isotope fractionation results determined from a chalcopyrite solution in 7 mol/L HCl give a fractionation factor of 0.58‰, which indicates that Fe may interfere with Cu fractionation.Comparison of Cu and Zn results suggests that the extent of Cu isotopic fractionation may signal the presence of so far unidentified polynuclear complexes in solution. In contrast, we see no compelling reason to ascribe isotope fractionation to the coexistence of different oxidation states. We further suggest that published evidence for iron isotopic fractionation in nature and in laboratory experiments may indicate the distortion of low-spin Fe tetrahedral complexes.The isotope geochemistry of transition elements may shed new light on their coordination chemistry. Their isotopic fractionation in the natural environment may be interpreted using models of thermodynamic fractionation.