对YS/T273.9-2006冰晶石中五氧化二磷测定方法的改进

<正>冰晶石作为电解铝生产中主要的原材料,其质量直接影响电解铝工业中电解效率和电解铝产品质量优劣。控制冰晶石产品中杂质含量使其在一定范围内,并且准确检测冰晶石中五氧化二磷含量是保证产品质量的一个重要手段。目前,五氧化二磷的测定方法主要有两种,一种是在pH 0.3或pH 0.3以下时加入钼酸铵使磷形成     

电感耦合等离子体原子发射光谱法测定工业电解质中钙、镁、锂

工业电解质中微量元素钙、镁、锂对电解槽的正常运行非常重要。本文采用高氯酸加热挥发除氟,以盐酸(1 1)溶解残渣,选用Ca317.9nm、Mg297.5nm、Li670.7nm作为分析谱线,考察了样品处理方法、共存元素干扰对测定结果的影响。建立了电感耦合等离子体原子发射光谱法测定工业电解质中钙、镁、锂的方法。结果表明：不同的电解质因其所含氧化铝的不同会有部分不溶杂质,但对微量元素的测定影响很小,可以忽略不计。共存元素铝和钠不干扰微量元素的测定。按照试验方法对2个电解质标准样品进行了测定,其测定值与标准值吻合。同时对不同电解槽的工业电解质样品进行了分析,其结果的相对标准偏差(RSD,n=11)在0.69%-5.68%之间,满足生产分析的需要。     

电感耦合等离子体原子发射光谱(ICP-AES)法测定工业电解质中钙、镁、锂

工业电解质中微量元素钙、镁、锂对电解槽的正常运行非常重要。采用高氯酸加热挥发除氟,以盐酸(1+1)溶解残渣,选用Ca 317.9nm、Mg 297.5nm、Li 670.7nm作为分析谱线,考察了样品处理方法、共存元素对测定结果的影响。建立了电感耦合等离子体原子发射光谱(ICP-AES)法测定工业电解质中钙、镁、锂的方法。结果表明:不同的电解质因其所含氧化铝的不同会有部分不溶杂质,但对微量元素的测定影响很小,可以忽略不计。共存元素铝和钠不干扰微量元素的测定。按照实验方法对2个电解质标准样品进行了测定,其测定值与标准值吻合。同时对不同电解槽的工业电解质样品进行了分析,其结果的相对标准偏差(RSD,n=11)在0.69%~5.7%,满足生产分析的需要。     

用氟离子电极对土壤中铝作直接电位法测定

本文提出用氟离子电极对土壤中铝作直接电位法测定。大大减少了以往的用终点电位滴定法测定土壤中铝含量的实验步骤与时间,并较大地提高了测定的准确度。方法是取一定量的土壤试液加入到pH为5,离子强度为1.0的缓冲溶液中,再加入一定量的F~-离子标液,让F~-与Al_(3 )络合稳定后,用氟离子电极测出溶液中的游离态F~-浓度,从而计算出Al~(3 )的总浓度。     

电感耦合等离子体原子发射光谱法测定镁钕合金中3种杂质元素的含量

采用电感耦合等离子体原子发射光谱法测定镁钕合金中硅、铝及铜3种杂质元素的含量。选择盐酸(1+1)溶液10mL溶解试样(0.1g),以克服合金的基体元素及其他共存元素的干扰为目标,选择测定上述3种元素的分析谱线依次为251.611,237.313,224.700nm。用0.1g高纯镁及与试样中含钕量近似的钕标准溶液作为基体,加入一定量的硅、铝和铜的标准溶液后,按试样相同的溶解方法处理并定容至100mL。按所选仪器工作条件进行光谱测定,并制作各元素的工作曲线。硅、铝、铜的检出限(3s)依次为0.006,0.002,0.01mg·L-1。对2个样品中的3种元素各测定6次,测定值的相对标准偏差均不大于3.7%。用标准加入法进行回收试验,测得回收率在92.0%~108%之间。     

无火焰原子吸收测定血清中的铝

用无火焰原子吸收法测定血清中的铝,样品用高纯水十倍稀释后,用标准加入法进行测定,不需使用基体改进剂和氘灯扣除背景。方法简单、准确、灵敏度高。用含铝20ng/ml的一份十倍稀释血清样,重复测十次,变异系数5%左右。     

火焰原子发射光谱法测定电解铝中痕量钾

建立了火焰原子发射光谱法检测电解铝中痕量钾的方法。用稀王水(1:1,V/V)边加热边溶解电解铝样品,冷却后转移到100 m L容量瓶,待用;为消除铝基体干扰,标准工作溶液需加入适量的铝,火焰原子发射光谱法直接测定。方法线性范围为0.010~0.120μg/m L,检出限(3σ)为0.4 ng/m L(n=11),连续9次测定0.040μg/m L钾标准工作溶液,其RSD为0.72%。分析了3种电解铝样品中钾含量,回收率范围为90.0%~100.0%。该方法可用于电解铝样品中痕量钾的检测。     

含锂沸石Li-FER提高PEO复合聚合物电解质电导率

通过离子交换方法使锂部分取代了镁碱沸石（FER）孔道壁上羟基中的氢，制得含锂沸石Li-FER. 将这种沸石作为无机填料加入到PEO/LiClO₄聚合物电解质中，可以使其室温电导率提高三个数量级以上. 电化学测量表明， 锂离子与PEO和含锂沸石中氧的相互作用提高了聚合物电解质中锂离子的迁移数. 另一方面， 采用XRD, DSC, PLM等方法研究了电解质的结晶状况.结果表明, Li-FER可以作为PEO链段结晶的成核剂，使PEO电解质的晶粒得到细化， 结晶度降低，为Li⁺的传输提供了更多的非晶区通道. 这是Li-FER的加入促使PEO聚合物电解质电导率提高的两个主要原因.     

氟离子选择电极法测定含铜蚀刻废液中氟含量方法探讨

准确测定含铜蚀刻废液中氟含量是含铜蚀刻废液中铜盐回收的关键,本文就含铜蚀刻废液中氟含量离子选择电极测定方法^[1～3]进行探讨与验证。通过样品前处理与试验,离子选择电极一次标准加入法测定下限为0.9mg·L^-1,离子选择电极标准曲线法测定下限为1.2 mg·L^-1;两种方法的相对标准偏差在1.2%～1.7%,两种方法的加标回收率在77%～102%,满足工程应用要求。     

电感耦合等离子体原子发射光谱法测定Cu-Ni-Mn钎料中铝、钽元素含量

采用电感耦合等离子体原子发射光谱法测定Cu-Ni-Mn钎料中的铝和钽元素含量。实验探讨了Cu-NiMn钎料中基体元素及共存元素对铝、钽元素分析谱线的光谱干扰情况,确定了合适的分析谱线和背景校正方法。铝、钽元素的分析谱线分别为396.152 nm和240.063 nm。根据Cu-Ni-Mn钎料中铝、钽元素含量范围,合成系列标准溶液,建立标准工作曲线,工作曲线的线性范围为0.05%~0.20%,线性相关系数分别为0.999 6和0.998 8,此方法用于测定铝、钽元素的检出限分别为0.001 2%和0.008 4%,相对标准偏差为2.43%~4.55%(n=8)。标准加入回收率为100%~119%。该法可用于测定Cu-Ni-Mn合金中的铝和钽含量。     

Spectrophotometric determination of fluoride in fluoride-bearing minerals after decomposition by fusion with sodium hydroxide

The decomposition of highly insoluble minerals (fluorspar and cryolite) by fusion with molten alkali-metal hydroxides is studied. The introduction of additives such as aluminium compounds or sodium peroxide to obtain total liberation of fluoride from calcium fluoride samples, is tested. The fusion is done in a silver crucible with a Bunsen burner. The cooled melt is easily soluble, giving solutions suitable for spectrophotometric fluoride determination by the Zr(IV)-fluoride-Erichrome Cyanine R method.     

X射线荧光光谱法测定电解锰中锰、硅、磷和铁含量

熔融制样X射线荧光光谱法测定电解锰中锰、硅、磷和铁含量。用熔融后的四硼酸锂制作铂金坩埚保护层,以BaO2做氧化剂,在马弗炉内通过逐渐升温来氧化电解锰,然后熔融制取玻璃熔片,用X射线荧光(XRF)光谱法分析电解锰中锰、硅、磷和铁含量。锰、硅、磷和铁的相对标准偏差RSD分别为0.23%、2.82%、0.31%和0.53%。与其它分析方法比较,其结果更稳定。有效消除了电解锰熔融制样过程中的坩埚腐蚀问题,分析误差可完全控制在国家相关标准允许的范围内,实现了电解锰中各元素的快速准确测定。     

Improved manufacture of AlF3 FROM H2SiF6

Experience gathered in aluminum fluoride production during nearly ten years and concurrent development work have resulted in an improved process technology amenable to a reliable large scale production.The recovery of fluoride values - as aluminum fluoride or cryolite - provides phosphate plants with marketable products and simultaneously alleviates the disposal of a hazardous waste product. Within the next years new plants featuring optimized processing conditions will go on stream.Within the framework of favorable conditions provided by the phosphate plant (e.g. amount and quality of acid, reuse of side products), process parameters (e.g. reaction, filtration, crystallization), equipment design (e.g. filters, vessels, dryer, calciner) and optimization of process stages were found to be decisive in obtaining reliably a good product at high yields.     

X射线荧光光谱法测定萤石中氟化钙

采用X射线荧光光谱仪可以快速准确测定萤石中总钙的含量.但测定其中氟化钙含量时,一方面,由于样品中碳酸钙计入钙量,从而造成氟化钙测定结果准确性较差.另一方面,铜、锌等金属元素在熔融制样时对铂金坩埚腐蚀较大,因此需要进行酸处理除去碳酸钙及铜、锌等金属元素.然而,样品经过酸处理后,质量会发生变化,造成熔剂与样品的比例不一致,从而影响测定结果.对样品前处理条件、XRF分析中熔片和仪器工作条件等进行了优化,建立了熔融制样、X射线荧光光谱法（XRF）准确测定萤石中氟化钙含量的方法.方法干扰少,具有良好的准确度和精密度,操作简单,提高了分析效率.     

The lead recovery during dry ashing of lead containing bone samples

Rabbit bones after lead injection were ashed at temperature 550 °C in platinum and porcelain crucibles yielding lead recovery about 0.8. An increase in the temperature up to 800 °C gives the same recovery in the platinum crucible, whereas in the porcelain crucible the recovery is lower.     

镍氢蓄电池材料用氧化锆布膜中铝含量的分析测试技术

运用N2O-C2H2火焰原子吸收光谱法进行镍氢蓄电池材料用氧化锆布膜中铝含量的分析测试技术,建立了铝的共振线、灯电流、火焰燃烧比等最佳实验条件．显示出该方法具有很好的灵敏度和重现性,具有操作简便、容易掌握、分析周期短、干扰小等优点．测定样品铝含量的相对标准偏差均小于1．0％（n=6）．标准加入回收率均在97．5％～98．6％范围内．适用于镍氢蓄电池材料用氧化锆布膜中铝含量的控制分析和样品系统分析．     

Determination of elements in lithium potassium niobate and lithium niobate containing vanadium by ICP-AES

The elements in lithium potassium niobate and lithium niobate containing vanadium (such as aluminum, lithium, niobium, potassium and vanadium) were determined by inductively coupled plasma atomic emission spectrometry after fusion of the sample with ammonium hydrogensulfate. The samples were completely decomposed and high precision results were obtained for the metallic elements. Oxygen has been determined by a helium carrier fusion thermal conductivity method using both a nickel capsule and tin as a melting flux in a graphite crucible.     

铝灰及其浸出液中氟的测定

铝灰中的氟化物是铝灰中的环境危害因子.使用X射线荧光光谱(XRF)法、X射线衍射(XRD)法对15份铝灰样品进行了元素及物相组成检测,使用SPSS 25.0对数据进行因子分析和聚类分析,将15份样品分成四类,从每类中选择1～2个样品,共选取5份样品作为代表进行后续实验.使用离子色谱法和氟离子选择电极法对铝灰浸出液中氟离...     

Sources and availability of raw materials for fluorine chemistry

The two most important sources of fluorine are the minerals fluorite, commercially known as fluorspar, and fluorapatite, commercially known as phosphate rock.The major consumers of fluorspar are the aluminum, chemical, and steel industries. Acid-grade fluorspar, one of three commercial grades, is used primarily to make hydrogen fluoride, which is then used to produce synthetic cryolite, aluminum fluoride, fluorocarbons, and other fluorochemicals. Elemental fluorine is prepared from anhydrous hydrogen fluoride by electrolysis. Fluosilicic acid is used primarily for water fluoridation but also to make aluminum fluoride and cryolite. Reported U.S. consumption of fluorspar was 753,000 tons in 1984. U.S. demand for fluorspar was projected to increase at an average annual rate of 2.7% between 1983 and 2000.U.S. production of finished fluorspar in 1984 was 72,000 tons. Fluosilicic acid production was 61,000 tons or 107,000 tons as equivalent fluorspar. More than 85% of domestic demand was imported, primarily from Mexico and the Republic of South Africa.A U.S. Bureau of Mines investigation of major fluorspar reserves and resources in market economy countries and China found approximately 900,000 tons of demonstrated and 1,200,000 tons of identified reserves in the United States. Total world demonstrated and identified reserves were 135 million tons and 262 million tons, respectively. The potential resources of fluosilicic acid were estimated at 12 million tons of equivalent fluorspar in the United States and 360 million tons for the total world. Fluorine reserves appear adequate through the year 2000 given current projections.