电感耦合等离子体发射光谱法同时测定锡矿石中锡钨钼铜铅锌

锡矿石是难分解的矿物,共生与伴生元素多,其中的锡钨钼在单一盐酸溶液中易沉淀,准确测定锡矿石中的主次量元素一直是分析技术难点。本文以过氧化钠为熔剂,高温熔融样品,在酒石酸-盐酸-双氧水体系中进行酸化,选用该矿种中仅含有少量的钴作为内标,建立了电感耦合等离子体发射光谱同时测定锡矿石中锡钨钼铜铅锌的分析方法。方法线性范围为0.00~40.0 mg/L;方法检出限为锡10 mg/kg,钨30 mg/kg,钼3.3 mg/kg,铜12 mg/kg,铅15 mg/kg,锌40 mg/kg;方法精密度(n = 9)小于5.0%,实际样品的测定值与传统化学方法及国家标准方法的测定值吻合较好。本方法采用过氧化钠碱熔锡矿石,溶样彻底,并省去了氢氟酸挥发硅的蒸酸过程,节约了样品处理时间;采用酒石酸-双氧水-盐酸体系溶解熔融物,有利于溶液中的锡钨钼形成稳定的络合物,避免了单纯盐酸体系下产生钨酸、钼酸和锡酸沉淀导致测定结果偏低的问题。     

电感耦合等离子体发射光谱法测定钼矿石中钴铬铜钼镍铅锡钨钇锌

采用盐酸-硝酸-氢氟酸-高氯酸-柠檬酸处理样品,电感耦合等离子体发射光谱法同时测定钼矿中钴、铬、铜、钼、镍、铅、锡、钨、钇、锌10个元素,筛选了不同溶矿方法和仪器参数条件。测定的相对标准偏差(RSD,n=11)均小于3.0%,经国家一级钼矿标准物质分析验证,结果与推荐值吻合。     

电感耦合等离子体发射光谱法测定工业硅中微量元素

采用电感耦合等离子体发射光谱法同时测定工业硅中可能存在的铝、铁、钙、镁、钾、钠、磷、钡、铍、镉、铈、钴、铬、铜、锂、锰、钼、镍、铅、钛、钒、钨、锌、砷、锶、铼、锑、硼28个微量元素,并以差减法计算基体硅的含量,实现了对试样基体及杂质元素含量的同时测定。方法对28个微量元素的回收率为94.0%～103.4%,精密度(RSD,n=10)低于3.0%。方法经国家实物标准物质验证,测定值与标准值基本相符。     

电感耦合等离子体发射光谱法(ICP-OES)测定钨铋矿石中的锡

钨铋矿石经过无水碳酸钠!过氧化钠(1∶3)混合剂高温熔融后,用热水浸取熔融物并酸化,分取适当溶液进行酸度调节后,用电感耦合等离子体发射光谱法测定锡,测定此类矿石,不用分离,方法简便快捷。结果表明,方法的检出限为0.0027mg/L;精密度小于5.5%;采用本方法与钨钼矿石化学分析方法中锡量测定法(GB/T 14352.13-2010)对照测定4个国家标准物质,结果与标准参考值相一致。     

电感耦合等离子体发射光谱法测定含锡矿石中的锡

通过用过氧化钠分解试样,盐酸-酒石酸-双氧水浸取,电感耦合等离子体发射光谱法测定样品中的锡。该方法检出限为10μg/g,相对标准偏差为1.95%~4.83%。该方法经国家一级标准物质验证,分析结果与国家标准值相符,且实验步骤简单,快速准确,提高了工作效率,可用于大批量样品的检测。     

全谱直读ICP发射光谱法测定地质样品中的钨、锡、钼

对地质样品中的锡、钨、钼三个项目连测进行了试验,分别采用硝酸、氢氟酸、高氯酸分解试样,盐酸提取和氢氧化钠熔融,沸水提取,在ICP发射光谱仪上测定钨、锡、钼等元素,精密度和准确度均能达到DZ/T130-2006的要求。     

基于二苯乙醇酸体系快速测定区域地质矿产调查样品中的钨钼

本文建立了一种快速分析区域地质矿产调查样品中钨钼的方法。试样经高温焙烧、碱熔分解,钨、钼与其它杂质元素所形成的氢氧化物沉淀分离;在二苯乙醇酸体系(0.25mol/L硫酸-0.04g/L二苯乙醇酸-0.10g/L二苯胍-20g/L氯酸钠)中,钼、钨分别于约-0.25V、-0.85V产生灵敏的平行催化波,根据极限扩散电流的大小同时测定这两种元素。该方法的测定下限(X0+3S)<0.10×10-6;准确度(|Δlog|)≤0.05;精密度(RSD)≤7.72%。国家标准物质测定值与标准值相符;实际样品测定值优于电感耦合等离子体发射质谱法。方法扩大了催化极谱法的适应性,提高了实际应用价值。     

电感耦合等离子体发射光谱法测定地表水和地下水中的硫酸根

建立了盐酸直接酸化地表水和地下水,电感耦合等离子体发射光谱法测定硫酸根含量的方法。方法检出限为0.031 mg/L。在硫波长182.0 nm处测定的线性范围为0.03~100 mg/L,182.6 nm处的线性范围为100~700 mg/L。对实际水样进行连续12次测定,方法精密度(RSD)为0.76%。经国家水标准物质验证,结果与标准值相符。方法快速、准确。     

电感耦合等离子体质谱法测定磷矿石中的碘

建立了电感耦合等离子体质谱法测定磷矿石中碘的方法。试样经磷酸、高氯酸分解,用氨水调至弱碱性,直接用电感耦合等离子体质谱法测定,方法检出限为0.33μg/g,加标回收率为95.0%~97.4%,精密度(RSD,n=12)为2.77%~3.17%。经磷矿石国家一级标准物质(GBW 07210和GBW 07211)验证,结果满意。     

五酸和硝酸微波消解法结合ICP-OES技术测定多金属矿中多种元素的对比研究

快速、准确测定多金属矿中的主次量元素需要根据多金属矿的具体类型选择不同的预处理方法。本文采集我国典型区域的铅锌、锡、钼、钒和铜镍等5种多金属矿,对比了盐酸-硝酸-高氯酸-氢氟酸-硫酸五酸微波消解和硝酸微波消解的溶样效果,应用电感耦合等离子体发射光谱法(ICP-OES)测定铜铅锌锡钨钼锰钛钒9种元素。通过国家标准物质分析验证,五酸微波消解的溶样时间较长,但一次可测定铜铅锌钼锰钒6种元素;硝酸微波消解的溶样时间短,但一次只能测定铜铅锌钼4种元素;两种方法的准确度和精密度高(RSD5%),检出限低(5.3~30 mg/kg),均适合在地质行业推广应用。而由于锡钨钛3种元素不能完全被酸溶解,上述两种消解方法均不适合。     

Solubility of tin,tungsten and molybdenum oxides in felsic magmas

Saturation versus undersaturation of granitic melts in tin, tungsten and molybdenum oxides is discussed on the basis of experimental data. Results of dry and hydrothermal experiments are evaluated under the assumption of ideal solubility of Sn, W and Mo oxides in granitic melts. A conservative interpretation arrives at concentration levels of 1000 ppm SnO₂, WO₃ and MoO₃ respectively, considered as the maximum solubility of these components in granitic melts at 750°C-800 °C. Such values are never reached in natural granites unaffected by hydrothermal alteration and therefore even highly evolved granites are expected to be undersaturated in these metals. Consequently cassiterite and scheelite are neither common liquidus minerals of ore-bearing granites nor restite minerals from partial melting events.     

改进的极谱法测定化探样品中的钨钼

试样经氢氧化钾熔融,水提取,采用二苯乙醇酸代替苯羟乙酸,在硫酸-二苯乙醇酸-二苯胍-氯酸钾体系中,利用JP—06A精密极谱分析计测定钨、钼,使测定的灵敏度大为提高。钨、钼的峰电位分别为-0.76 V、-0.26 V(相对饱和甘汞电极),钨、钼含量在1.0~100.0 ng/mL时,峰高与浓度呈线性关系。方法经国家一级标准物质检验,测定结果与标准值吻合,方法精密度(RSD,n=12)钨、钼均小于5%。     

^40Ar-^39Ar Isotopic Dating of the Xianghualing Sn-polymetallic Orefield in Southern Hunan, China and Its Geological Implications

The Xianghualing Sn-polymetallic orefield in Hunan Province, southern China, is a large-size tin orefield. Although numerous studies have been undertaken on this orefield, its genesis, mineralization age, and tectonic setting are still controversial, mainly because of the lack of reliable geochronological data on tin mineralization. The 40Ar/39Ar stepwise heating dating method was first employed on muscovite from different deposits in this orefield. The muscovite sample from the Xianghualing Sn-polymetallic deposit defines a plateau age of 154.4±1.1 Ma and an isochron age of 151.9±3.0 Ma; muscovite from the Xianghuapu W-polymetallic deposit yields a plateau age of 161.3±1.1 Ma and an isochron age of 160.0±3.2 Ma; muscovite from the Jianfengling greisen-type Sn-polymetallic deposit gives a plateau age of 158.7±1.2 Ma and an isochron age of 160.3±3.2 Ma. The tungsten-tin mineralization ages in the Xianghualing area are therefore restricted within 150-160 Ma. The tungsten -tin mineralization in Xianghualing occurred at the same time as the regional tin-tungsten mineralization including the Furong tin orefield, Shizhuyuan tungsten-tin polymetallic deposit and Yaogangxian tungsten-polymetallic deposit. Thus, the large-scale tungsten-tin metallogenesis in South China occurring at 160-150 Ma. probably is closely related to asthenospheric upwelling and crust-mantle interaction under a geodynamic setting of crustal extension and lithosphere thinning during the transformation of tectonic regimes during the Mid-Late Jurassic.     

Hydrometallurgical processing and recovery of molybdenum trioxide from spent catalyst

Hydrometallurgical processing of spent hydrodesulphurisation (HDS) catalyst for the recovery of molybdenum using sodium carbonate and hydrogen peroxide mixtures was investigated. The results indicated that the recovery of molybdenum was largely dependent on the concentrations of Na₂CO₃ and H₂O₂ in the reaction medium, which controls the acidity of the leach liquor and carry over of impurities such as Al, Ni, P, Si and V. Leaching process was exothermic and leaching efficiency of molybdenum decreased with increasing solid to liquid ratio. Large scale leaching of spent catalyst, under optimum conditions: 20% pulp density, 85 g/L Na₂CO₃, 10 vol.% H₂O₂ and 1 h reaction, resulted a leaching efficiency of 84% Mo. The obtained leach liquor contained (g/L): Mo — 22.0, Ni — 0.015 and Al — 0.82, P — 1.1, Si — 0.094 and minor quantities of V — 8 mg/L, As and Co — < 1 mg/L. Recovery of Mo from leach solution as MoO₃ of 97.30% purity was achieved by ammonium molybdate precipitation method.     

硫氰酸钾分光光度法有效提高铀矿石中钼的测定精度

在国标GB/T 14353.9—1993基础上,以氯化亚锡为还原剂,硫氰酸钾为络合剂,用国家一级合成硅酸盐光谱分析标准物质验证,对比不同熔矿方法和不同酸性介质对钼最低检出范围的影响,优化了用硫氰酸钾比色法有效检测铀矿石中含量≥10.0μg/g钼的实验方法。数据结果稳定可靠,步骤简单,测得钼的最低检出限可降低至10.0μg/g。方法的测定值与等离子体发射光谱的分析结果相符,可满足实验室内铀矿石批量检测的要求。     

TBP萃淋树脂微色谱柱分离富集钼的研究及应用

研究了ＴＢＰ萃淋树脂微色谱柱分离富集微量钼的柱性能,确定了分离钼的最佳条件。在减压条件下,运用零空床体积洗脱技术,以３ｍｏｌ／ＬＨＣｌ为上柱介质,０．５ｍｏｌ／ＬＨＣｌ洗脱,可使钼（ＶＩ）与钨（Ⅵ）、铁（Ⅲ）、锡（Ⅳ）等干扰离子快速分离,采用邻氯苯基荧光酮胶束增溶光度法,测定矿石中微量钼,结果满意。     

极谱催化波对化探样品中微量钨钼的同时测定

本文着重研究了利用极谱法测定钨钼的简便方法,如一次扫描同时读出钼钨的波高,一次性加入混合底液等,该方法使钨钼的测定变得轻松快捷。方法经国家一级标样检验,测定结果与标准值相符。本方法适用于钨含量在0.4×10-6～100×10-6钼含量在0.3×10-6～50×10-6的测定。