原子荧光光度法测定工业废水中的砷和硒

本文采用原子荧光光谱法,研究测定水样中砷和硒的技术.结果表明：用10％盐酸和1％硫脲-1％抗坏血酸混合试剂处理样品,并以1.0％硼氢化钾和0.5％氢氧化钠为还原剂,在5％的盐酸介质测定砷和硒.砷和硒的检出限分别为：0.20μg/L和0.13μg/L,本方法具有操作简便、快速、基体干扰少、灵敏度高等优点,可用于工业废水样中砷和硒的联合测定.     

氢化物发生-原子荧光光谱法同时测定尿中砷和碲的方法研究

目的:建立同时检测尿中砷和碲的原子荧光光谱法。方法:尿样经硝酸-盐酸湿法消解后采用原子荧光光谱法同时测定其中砷和碲含量。结果:As在0.1～20μg/L时线性关系良好,检出限为0.1μg/L,加标回收率在87.6%～93.6%之间;Te的线性范围为0.2～10μg/L,检出限为0.2μg/L,加标回收率在81.3%～97.5%之间。相对标准偏差分别为2.4%和4.3%。结论:该方法简单、准确、有效,可应用于大批量尿中砷和碲的同时检测。     

氢化物-原子荧光法测定水中痕量砷、硒、汞

采用氢化物－原子荧光法测定水中痕量的砷、硒、汞，该法大大提高了灵敏度，砷，硒，汞的检出限分别为0.40μg/L,0.50μg/L，水样的回标回收率在95％－105％之间，其相对标准偏差小于5．0％。该方法已成功地用于大批量水样中砷、硒、汞的测定。     

氢化物发生原子荧光光谱法联合测定水中痕量砷和硒

采用氢化物发生原子荧光光谱法,研究了联合测定水样中砷和硒的技术。用10%盐酸和1%硫脲-1%抗坏血酸混合试剂处理样品,并以2.0%硼氢化钾和0.5%氢氧化钠为还原剂,在5%的盐酸介质测定砷和硒。砷和硒的检出限分别为:As:0.05μg/L和Se:0.09 ug/L。本方法具有操作简便、快速、基本干扰少、灵敏度高等优点,可用于水样中砷和硒的联合测定。     

氢化物发生-原子荧光光谱法测定环境水体中痕量锑

建立了采用氢化物发生-原子荧光光谱法测定环境水体中痕量锑的方法.通过优化仪器工作条件和所用试剂的浓度,确定仪器的光电倍增管负高压为310 V,灯电流为75 mA,硼氢化钾溶液和载流盐酸浓度分别为20 g/L和5％.方法的检出限和定量限分别为0.02μg/L和0.06μg/L,线性范围为0.06～5.0μg/L.分别连续测定3个不同浓度锑标准溶液12次,其相对标准偏差在1.33％～2.45％.选取矿化度不同的两个水样进行加标回收试验,其加标回收率为95.12％～103.5％,相对标准偏差(n=12)为0.97％～3.12％.     

原子荧光光度法测定水中砷方法的应用

根据GB/T5750-2006《生活饮用水标准检验方法》,对水中砷用原子荧光光度法进行检测应用。经实验验证,该方法砷标准的检测浓度在1.0-10.0μg/L范围内,线性良好;用国家环境保护总局标准样品研究所GSBZ50004-88砷标准样,砷测定值为228μg/L、标准值为(226±17)μg/L,测定值在标准范围内;水样加标回收率测定中,砷加标回收率在97%～99%之间。砷标准溶液低浓度和高浓度分别做7个平行样,相对标准偏差均小于1.0%,精密度较好。从以上数据可以看出,该方法检测水中砷,结果准确可靠,可以适用于在实际工作中运用此方法测定水中砷。     

原子荧光光度法测定固体废物中砷的方法验证

为对我国环境保护与控制提供技术支持,进一步完善固体废物中重点参数,本文对HJ 702—2014《固体废物砷、汞、硒、铋、锑的测定微波消解/原子荧光法》中砷的测定进行6个方面的验证：线性关系、方法检出限、测定下限、精密度、准确度和实际样品加标回收率。结果表明,线性关系达到0.999 8;当称取0.5 g固体废物样品验证砷（全量）时,测得0.009μg/g检出限、0.036μg/g的测定下限,当移取40 m L固体废物浸出液验证砷（浸出液）时,测得0.08μg/L的检出限、0.32μg/L的测定下限;砷（全量）、砷（浸出液）的相对标准偏差分别为0.35%～1.0%、1.2%～2.9%;实验室砷（全量）有证标准物质相对误差分别为-4.6%～0.85%,砷（浸出液）标准浓度的相对误差分别为0.25%～3.0%;固体废物砷（全量）加标回收率分别为93.7%～97.5%,固体废物砷（浸出液）加标回收率分别为96.0%～98.1%。各项指标均满足标准方法要求,证实实验室具备原子荧光光度法测定固体废物中砷的试验条件和技术能力。     

氢化物发生原子荧光光度法测定果蜡中的砷含量

采用微波消解法对某公司生产的吗啉脂肪酸盐果蜡进行前处理,应用氢化物发生原子荧光光度法测定果蜡中砷含量。实验优化了载流HCl和还原剂KBH4的浓度条件,并测定了标准曲线、方法检出限、精密度和加标回收率。当盐酸浓度为5.0%,硼氢化钾浓度为20.0 g/L,测定6.0μg/L的砷溶液时,荧光强度达最大值,仪器灵敏度最高。砷浓度范围在2.0~10.0μg/L,标准曲线方程为:I=125.945 C+144.86,相关系数为0.999 3,方法检出限为0.0305μg/L,精密度为1.61%。测定了果蜡样品中砷加标量为2.0、4.0、6.0μg/L时的加标回收率,回收率在92.65%~101.18%之间,平均回收率为95.78%。实验测得该批次果蜡中砷含量为0.048 mg/kg,满足国家标准砷元素限量要求。     

原子荧光光谱法测定地表水中的砷

运用原子荧光光谱法测定地表水样中砷。用10%盐酸、10%抗坏血酸-10%硫脲混合溶液处理样品,1.0%硼氢化钾和0.5%氢氧化钠作为还原剂,在5%盐酸介质中测定砷。通过检测,砷检出限为:0.18μg/L,砷的加标回收率为96%~107%,本测试方法有操作简便、基体干扰少、灵敏度高、快速等优点,可用于地表水样中砷快速测定。     

原子荧光法同时测定生活污水中的砷和硒

本文采用AFS-830双道原子荧光光度计同时测定生活污水中的砷、硒。测定结果表明：在0～10μg/L范围内砷具有良好的线性关系（r=0．9996），在0～100μg/L,范围内硒具有良好的线性关系（r=0．9996）：砷、硒的检出限分别为0．08μg/L，0．17μg/L：砷、硒的相对标准偏差分别为3．600／0、4．51％；该方法简单、快速、准确可靠，符合现代仪器分析的技术要求，值得推广和应用。     

原子荧光光谱法测定饮用水中砷和硒

本文采用AFS-230型原子荧光光度计同时测定饮用水中的砷硒,选择了最佳的仪器条件。测定砷的线性范围为0～10ug／L（r=0．9997）;测定硒的线性范围为0～1ug／L（r=0．9994）。砷、硒的检出限分别为0．03ug／L、0．003ug／L。     

改性麦饭石去除饮用水中的砷

饮用水中砷超标会严重危害人的身体健康。该文利用MnO：对麦饭石进行改性,制备了一种高效的吸附剂;同时研究了在不同pH值、接触时间、改性麦饭石的投加量及砷的初始浓度条件下,改性麦饭石对饮用水中As（V）的去除。研究结果表明：在以上不同条件下,改性麦饭石对水中As（V）均有一定的去除效果。当pH值为6、接触时间为60min、改性麦饭石投加量为1000mg／L、水中As（V）的初始浓度为100μg／L时,改性麦饭石对饮用水中的As（V）的去除率为91％,此时水中砷的含量低于国家生活饮用水卫生标准（10μg／L）。     

Volatilization of mercury,arsenic and selenium during underground coal gasification

Mercury, arsenic and selenium are trace elements well-known for their high volatility in underground coal gasification (UCG) which can lead to environmental and technical problems during gas utilization. In this paper, the volatilization of mercury, arsenic and selenium from coal in a seam during the process of UCG were investigated, based on comparison of their volatility during the transformation of coal to char and the conversion of char to ash. Three types of coal were involved in this study. The results indicate that the volatility of mercury, arsenic and selenium during UCG in the seam follows the sequence of Hg>Se>As. Mercury and selenium show volatility higher than 90% from coal to ash. The volatility of arsenic is lower than 60% as confirmed by arsenic enrichment in UCG ash. Arsenic volatilization during UCG is also enhanced by increasing temperature, which is different from the result during the combustion of crushed coal. Coal type has obvious effect on element volatilization. The higher the coal reactivity, the easier is the evaporation of the elements from coal in the seam. At the same time, thermodynamic equilibrium calculations using MTDATA program were performed to predict the possible species in UCG gas. With regard to UCG gas at the production well, mercury presents as Hg(g), H₂Se(g) is the main gaseous species of selenium, whereas arsenic occurs in condensed phase as As₂S₃ and As. The effect of the pressure on the equilibrium composition of the gas results in major changes of the proportions of the species. High pressure leads to the formation and enhancement of the reduced species and increases the condensation temperature of the volatile elements.     

Effect of operating conditions in removal of arsenic from water by nanofiltration membrane

The removal of arsenic from synthetic waters and surface water by nanofiltration (NF) membrane was investigated. In synthetic solutions, arsenic rejection experiments included variation of arsenic retentate concentration, transmembrane pressure, crossflow velocity and temperature. Arsenic rejection increased with arsenic retentate concentration. Arsenic was removed 93-99% from synthetic feed waters containing between 100 and 382 μg/L as V, resulting in permeate arsenic concentrations of about 5 μg/L. Under studied conditions, arsenic rejection was independent of transmembrane pressure, crossflow velocity and temperature. In surface water, the mean rejection of As V was 95% while the rejection of sulfate was 97%. The co-occurrence of dissolved inorganics does not significantly influence arsenic rejection. The mean concentration of As in collected permeated was 8 μg/L. The mean rejection of TDS, total hardness and conductivity were 75, 88 and 75% respectively.     

Kinetic Modeling of Arsenic Removal from Water by Ferric Ion Loaded Red Mud

A laboratory study was conducted to investigate the ability of ferric ion loaded red mud (FRM) for the removal of arsenic species from water. The adsorbent material was characterized by scanning electron microscopy, X-ray diffraction, and Fourier transform infrared spectroscopy. For an initial arsenic concentration lower than 0.3 mg/L, the FRM with a dosage of 1 g/L was able to reduce As(III) at pH 7 below 10 µg/L, the maximum contaminant level (MCL) of arsenic in drinking water set by the World Health Organization. In the case of As(V) removal, FRM was also particularly effective in reducing the initial arsenic concentration value of 1 mg/L at pH 2, below the MCL requirement of arsenic for drinking water. According to kinetic sorption data, the initial stage of adsorptions of As(III) and As(V) onto FRM were mainly governed by the external diffusion mechanism; however, upon saturation of the external adsorbent surface, the arsenic species were eventually adsorbed by intraparticle diffusion mechanism. The present results are promising for using the very inexpensive FRM as a low-cost material that is effective in remediating drinking waters contaminated with low concentrations of arsenic species. We report here the sorption kinetics and adsorption mechanisms of As(III) and As(V) on the FRM that has not been decsribed previously.     

原子荧光法同时测定水中砷和硒的最佳条件

原子荧光法同时测定砷和硒时,两元素之间会互相干扰测定。该文通过大量试验优化条件参数,调整了硼氢化钾浓度和载流盐酸浓度,总结出砷和硒同时测定的最佳条件,并对该条件下的精密度和准确度进行了评估。结果表明硼氢化钾浓度为3．0％和盐酸浓度为10％的条件下,同时测定砷和硒,操作简便,数据准确可靠。     

Removal of Trace Arsenic to Meet Drinking Water Standards Using Iron Oxide Coated Multiwall Carbon Nanotubes

This study presents the removal of trace level arsenic to meet drinking water standards using an iron oxide-multi-walled carbon nanotube (Fe-MWCNT) hybrid as a sorbent. The synthesis was facilitated by the high degree of nanotube functionalization using a microwave assisted process, and a controlled assembly of iron oxide was possible where the MWCNT served as an effective support for the oxide. In the final product, 11 % of the carbon atoms were attached to Fe. The Fe-MWCNT was effective in arsenic removal to below the drinking water standard levels of 10 μg L(-1). The absorption capacity of the composite was 1723 μg g(-1) and 189 μg g(-1) for As(III) and As(V) respectively. The adsorption of As(V) on Fe-MWCNT was faster than that of As(III). The pseudo-second order rate equation was found to effectively describe the kinetics of arsenic adsorption. The adsorption isotherms for As(III) and As(V) fitted both the Langmuir and Freundlich models.     

氢化物发生-原子荧光法测定水中的痕量砷

文章采用氢化物-原子荧光法(HG-AFS)对廊坊地表污水和浅井水中的痕量砷进行了测量与研究,探讨了测水中痕量砷的条件。测定结果为地表污水砷含量为6.5512μg/L,浅井水砷含量为0.8692μg/L。该方法检出限为0.0317μg/L,加标回收率为91%～106%,结果令人满意。