流动注射在线富集-火焰原子吸收光谱法测定痕量铅

在流动注射分析体系中,用装有黄原脂棉的微型柱对溶液中Pb2+进行在线富集,用3.0 mol/L盐酸洗脱柱上富集的Pb2+,火焰原子吸收光谱法在线测定痕量Pb2+,测定的灵敏度可提高65倍。方法测定的线性范围为0.5-100μg/L,用于环境水样中痕量Pb2+的测定,回收率在97%-102%之间,相对标准偏差小于4.0%。     

六氰合铁酸铁/全氟磺酸 聚四氟乙烯共聚物复合膜修饰玻碳电极差分脉冲伏安法测定铅和镉

利用电聚合的方法将普鲁士蓝修饰到玻碳电极表面,然后修饰上全氟磺酸 聚四氟乙烯共聚物(Nafion)膜制成修饰电极。利用差分脉冲伏安法（DPV）对Pb2+和Cd2+在该修饰电极上的电化学行为进行了研究,建立了差分脉冲伏安法灵敏测定Cd2+和Pb2+的新方法。对富集电位、富集时间以及Nafion用量等实验条件进行了优化。在01 mol/L pH 45的NaAc HAc缓冲液中,在-11 V处搅拌富集450 s,用DPV分别测定-048 V和-073 V处的氧化峰电流。溶出峰电流与Pb2+和Cd2+的浓度分别在5×10-8~5×10-5 mol/L和2×10-8~2×10-5 mol/L范围内呈良好的线性关系,相关系数分别为0995和0992。检出限分别为5×10-9 mol/L (Pb2+)和2×10-9 mol/L(Cd2+) (S/N=3)。方法用于水样中Cd2+和Pb2+的测定,测定值与原子吸收光谱法的结果相一致,相对标准偏差为21%~38%。     

流动注射在线共沉淀火焰原子吸收光谱法测定氯化钴溶液中痕量铅

为解决钴冶金生产中痕量铅的快速监控问题, 将流动注射在线富集分离技术与火焰原子吸收光谱检测方法相结合测定了氯化钴溶液中痕量铅。研究了铅的富集和分离条件, 结果表明, 用填充脱脂棉的微型锥形过滤器作为过滤柱, 以硝酸铁作为共沉淀剂, 在pH10的氨性缓冲介质中铁和铅生成氢氧化物共沉淀, 富集在过滤柱上, 可与高钴基体分离, 过滤柱上铅经盐酸（1+9）洗脱后用火焰原子吸收光谱法测定。在283.3nm波长处测得铅的特征浓度为0.008mg/L（1%吸收）, 检出限为5μg/L, 样品中铅测定结果的相对标准偏差为6.1%（n=11）, 满足了快速分析的要求。     

强酸阳离子交换纤维柱分离-石墨炉原子吸收光谱法测定金属铟及其盐中镉

研究表明,当In的共存量大于或等于400倍Cd量时,石墨炉原子吸收光谱(GFAAS)法直接测定Cd的误差≥+5%。采用强酸阳离子交换纤维柱,控制试液流速为0.6 mL/min进行交换,用相同流速的1.2 mol/L HNO3淋洗交换柱,Cd从纤维柱上首先被洗脱而使之与In达到分离,有效地消除了In对Cd的测定干扰。In与Cd质量比(mIn∶mCd)在100∶1~1 000 000∶1之间,经过纤维柱分离,GFAAS测定Cd的检出限(3S)为1.5×10-5μg/mL,线性范围为5.0×10-5~1.0×10-2μg/mL;加标回收率为98%~102%,RSD(n=6)为0.8%~1.5%。测定金属铟和硫酸铟中Cd的含量分别为17.6μg/g和1.86μg/g,加标平均回收率分别为100%和99%,RSD(n=6)分别为2.0%和2.3%。     

阴离子交换固相萃取在测定铜矿和粗铜中金的应用

采用新型阴离子交换树脂作填充剂,制得固相萃取柱,经稀盐酸洗涤后,应用于含金样品溶液中金的分离富集。对分离和富集金的条件进行研究,结果表明,用25 mL10%(V/V)盐酸试液以2 mL/min流速过柱,然后用30 g/L硫脲盐酸溶液洗脱柱上的金,可实现样品溶液中0.1~5.0μg/mL金的富集和洗脱。洗脱后的金用电感耦合等离子体发射光谱仪和火焰原子吸收分光光度计测定,大部分易挥发元素、常见金属离子以及较大量Pt(,Pd2+,Ir(,Rh(Ⅲ),Ru(Ⅲ),W(,Mo(对测定没有影响。方法已应用于铜精矿和粗铜中金的检测,结果与火试金法一致,相对标准偏差(RSD,n=5)均小于3.5%,回收率在95%以上。     

介孔分子筛SBA-15分离富集-火焰原子吸收光谱法测定矿样中铅

研究了介孔分子筛SBA-15材料对痕量Pb2+的分离富集性能,探讨了溶液pH值、温度、洗脱条件及共存离子对铅分离富集的影响。在最佳实验条件下,介孔分子筛SBA-15能定量、快速吸附试液中的痕量Pb2+,其静态饱和吸附容量为5.36 mg/g,吸附在介孔分子筛SBA-15上的Pb2+可用0.05 mol/L HNO3-CH3COOH完全洗脱,洗脱下来的Pb2+用火焰原子吸收法测定,方法线性范围为0.05~25.00μg/mL,铅的检出限为35 ng/mL。该方法已用于标准矿样和日常矿样中铅的测定,两个标准矿样测定结果的相对标准偏差(RSD)分别为3.8%和4.5%(n=5),日常矿样的加标回收率在98.7%~106%之间。     

流动注射在线离子交换火焰原子吸收光谱法测定痕量银

用流动注射在线离子交换技术对Ag+进行在线富集,柠檬酸作掩蔽剂消除Fe3+,Al3+等离子的干扰,硝酸溶液作洗脱液,将Ag+从离子交换柱中洗脱,火焰原子吸收法测定,测定灵敏度可提高11倍。方法的测定范围为0.01～1.0μg/mL,进样频率为10样/h。方法用于自来水及井水中痕量银的测定,结果令人满意。     

固相萃取-电感耦合等离子体原子发射光谱法测定磷矿及磷肥中镉和铅

使用电感耦合等离子体原子发射光谱法(ICP-AES)直接测定磷矿及磷肥中Cd和Pb,受P和Ca等共存元素的干扰。当待测液中P和Ca的质量浓度分别大于Cd和Pb的10倍时,直接测定Cd、Pb结果的相对误差均大于5%,而磷矿及磷肥中P和Ca相对于Cd和Pb的含量远高于此倍数。研究表明,在pH≈2并含有0.01g/mL抗坏血酸和0.20mol/L KI试液中,强碱性阴离子交换纤维(SBAEF)能够定量萃取试液中的Cd(Ⅱ)和Pb(Ⅱ),而Ca~(2+)、PO_4~(3-)和其他共存的阳离子不被萃取;被SBAEF萃取的Cd(Ⅱ)和Pb(Ⅱ),能够通过0.07mol/L EDTA溶液定量洗脱后,使用ICP-AES测定,从而消除了P和Ca等共存组分对测定的干扰。Cd和Pb的质量浓度分别为1.00×10~(-3)~2.00μg/mL和2.00×10~(-2)~40.0μg/mL时与其发射强度呈线性,线性相关系数R2分别为0.999 294和0.999 984。方法中Cd和Pb的测定下限分别为6.00×10~(-2)和2.00×10-1μg/g。按照实验方法测定模拟样品中Cd和Pb,测定值和理论值相吻合。方法应用于实际磷矿和磷肥样品中Cd和Pb的测定,结果的相对标准偏差(RSD,n=5)不大于4.4%。分离方法也适用于火焰原子吸收光谱法(FAAS)测定磷矿和磷肥中Cd和Pb。     

金橙G螯合树脂分离富集样品中铂、铑的研究

合成了金橙G螯合树脂,并用于分离富集样品中的铂、铑.实验研究表明,分离富集试液酸度为pH 1.0、分离柱高为200 mm、通过分离柱的试液流速为0.4 mL/min时,加入铂、铑标准、物质的回收率在94.5%～103%之间.标准样品经金橙G螯合树脂分离富集后,采用极谱法连续测定铂、铑,测定结果与标准值相吻合.     

改性纳米二氧化钛分离富集电感耦合等离子体原子发射光谱法测定地质样品中金钯铑

纳米TiO2用二苯基硫脲修饰后得到改性纳米TiO2,改性纳米TiO2对Au3+、Pd2+和Rh3+有很强的吸附能力,被用于Au3+、Pd2+和Rh3+分离富集。将该分离富集方法与电感耦合等离子体原子发射光谱法(ICP AES)相结合建立了测定地质样品中Au、Pd和Rh的新方法。考察了溶液酸度、洗脱条件和干扰离子等因素对分析物的分离富集影响。结果表明,在pH 40,Au3+、Pd2+和Rh3+可被改性纳米TiO2定量富集,吸附率在95%以上;而K+、Na+、Ca2+、Mg2+、Zn2+、Ni2+、Ba2+、Co2+、Cd2+和Mn2+不被吸附,Fe2+、In3+和Ga3+部分被吸附,但对测定没有影响。吸附的贵金属离子可用20 g/L CS(NH2)2 和 2 mol/L HCl溶液完全洗脱。在优化的实验条件下,吸附剂对Au3+、Pd2+ 和Rh3+的吸附容量分别为2163 mg /g, 1282 mg/g和1956 mg/g。本法对Au3+、Pd2+和Rh3+的检出限(3σ)分别为：061 ng/mL, 058 ng/mL和189 ng/mL,样品测定结果的相对标准偏差(RSD)分别为17%, 26%和18 (n=11)。该法应用于标准样品(GBW07293)中Au3+、Pd2+和Rh3+的测定,测定值与认定值相符。     

China's Major Non-ferrous Metals Imports & Exports

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Zinc Production by Province in 2014

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80% of Chinese Firms Purchasing Overseas Mines Ended up in the Red

<正>Minmetals Resources acquired the world’s largest copper mine under construction for USD5.85 billion.One after another,listed companies Jien Nickle,China Molybdenum and Chihong Zinc and Germanium raised money to get involved in overseas mining projects…SOEs and private enterprises are engaged in a frenzy of overseas mine purchasing.A reporter with Economic     

Copper Processing Profit Dropped Sharply,Copper Consumption Will Face Impact in the Second Half of the Year

正Judging from China’s copper consumption field,the biggest consumption unit is electric power,which accounts for 47%of total consumption;it is followed by light industry sector,including household electrical appliance,machinery,durable goods and hardware etc,which accounts for 22%of total consumption;followed by transportation field,     

Central Geological Prospecting Fund Newly Added 16.47 Million Tonnes of Bauxite in 2013

正In 2013,the Central Geological Prospecting Fund(CGPF)Project newly discovered 15 ore fields,including 3 large above ore fields,and 5medium sized ore fields.The reporter learned from the recently published"Annual Report of Central Geological Prospecting Fund Project(2013)"that,from 2006 to 2013 the CGPF     

Manufacturers of Copper Tube for Central Air Conditioner Use Face Mounting Pressure in the Final Quarter of the Year

正This year,the investment growth rate of real estate industry continued to slow down,sold area of commercial housing also dropped significantly,which brought huge pressure to the domestic air conditioning manufactures.In the first half of the year,by relying on high growth in national financial expenditure,along with investment in public infrastructure     

Xinjiang Ranks No.1 in Production of Primary Aluminum in China

正Kang Yi,Honorary Chairman of China Nonferrous Metals Industry Association,said recently at the Forum on Development of the Non-ferrous Metals Industry in Central and Western China held in Zhengzhou that,as more and more electrolytic aluminum factories in Xinjiang came into operation,the electrolytic aluminum output of Xinjiang had reached2,275,000 tons in the first 7 months this year,     

Shenhuo Coal Industry and Electricity Power Completed800,000 t/a Aluminum Project in Xinjiang

正"Xinjiang project has been completed according to schedule,but total completion and total start of production are two different concepts,after completion it still needs a gradual process of reaching production target."On the morning of November 3,Shenhuo Coal Industry and Electricity Power told investors the above statement on the investor interaction platform.     

Guangdong Metal Transaction Center has Become the Second Largest Precious Metal Transaction Platform Nationwide

正The reporter learned from Guangdong Province Precious Metal Transaction Center that in 2013the Center maintained healthy development momentum,and had become the second largest precious metal transaction platform in China in terms of market size;currently Guangdong is quickening steps of financial innovation for the Center,aiming to build a transaction center with international core competitiveness.     

Seven Rare Earth Projects Involving Close to 3 Billion Yuan Investment Landed In the HighTech Zone

正On May 22,Baotou Rare Earth Industry Cooperation Consultation MeetingProject Agreement-signing Ceremony was held in Ningbo,nearly 40 enterprises from Ningbo,Guangdong,Hunan,and Shanxi participated in project consultation.After multi-lateral communication,agreements were signed for a total of 7 rare earth projects successfully.