Determination of selected semi-volatile organic compounds in water using automated online solid-phase extraction with large-volume injection/gas chromatography/mass spectrometry

A rapid, sensitive, and cost-effective analytical method was developed for the analysis of selected semi-volatile organic compounds in water. The method used an automated online solid-phase extraction technique coupled with programmed-temperature vaporization large-volume injection gas chromatography/mass spectrometry. The water samples were extracted by using a fully automated mobile rack system based on x-y-z robotic techniques using syringes and disposable 96-well extraction plates. The method was validated for the analysis of 30 semivolatile analytes in drinking water, groundwater, and surface water. For a sample volume of 10 mL, the linear calibrations ranged from 0.01 or 0.05 to 2.5 μg·L⁻¹, and the method detection limits were less than 0.1 μg·L⁻¹. For the reagent water samples fortified at 1.0 μg·L⁻¹ and 2.0 μg·L⁻¹, the obtained mean absolute recoveries were 70%–130% with relative standard deviations of less than 20% for most analytes. For the drinking water, groundwater, and surface water samples fortified at 1.0 μg·L⁻¹, the obtained mean absolute recoveries were 50%–130% with relative standard deviations of less than 20% for most analytes. The new method demonstrated three advantages: 1) no manipulation except the fortification of surrogate standards prior to extraction; 2) significant cost reduction associated with sample collection, shipping, storage, and preparation; and 3) reduced exposure to hazardous solvents and other chemicals. As a result, this new automated method can be used as an effective approach for screening and/or compliance monitoring of selected semi-volatile organic compounds in water.     

Addressing the environmental risk of persistent organic pollutants in China

The Stockholm Convention on persistent organic pollutants (POPs) was adopted in 2001. This year is the 10th anniversary of the adoption of the Convention. Until now, 22 chemicals or chemical categories have been listed as POPs in the Stockholm Convention. The POPs Research Center was established in Tsinghua University in the same year when the Convention was adopted. In the last ten years, much work has been done by Chinese researchers to understand the environmental risk of POPs in China. This article aims to review the recent research progress of our POPs Research Center and some other Chinese researchers’ studies in addressing the environmental risk of POPs, including the priority screening and inventory study of POPs, monitoring and modeling of POPs pollution and exposure, and environmental risk assessment and modeling of POPs. Although great advances in addressing the environmental risk of POPs have been made in recent years, we are still facing quite a few problems, such as data scarcity and uncertainty in environmental risk assessment of POPs. The study on the effect of POPs mixtures is in its infancy and currently POPs are usually assessed from legal perspective by risk assessment of single chemicals. These problems should be well addressed by further efforts. Further studies should also be taken in future to study environment risk of POPs by considering aspects of coupled dynamics between climate processes and POPs. Such sound scientific, riskbased information can support decision-making aiming to effectively minimize the risk level of POPs.     

气相色谱法测定环境空气中吡啶

建立了用气相色谱法测定环境空气中吡啶的方法。环境空气中吡啶活性炭吸附,二硫化碳解吸,DB-200毛细管柱分离,直接进样分析,氢火焰离子化检测器检测,时间定性,峰面积定量,吡啶回收率为91．5％～103．1％,当采样体积为20L,吡啶最低检出质量浓度分别为0．006mg/m 3。本方法前处理简便,分离度好,分析灵敏度高,满足环境分析要求。     

气相色谱法测定海洋生物体中有机磷农药残留

建立了气相色谱法测定海洋生物体中乐果、甲基对硫磷和马拉硫磷残留量的方法.海洋生物体中有机磷农药残留用丙酮经超声波提取、弗罗里硅土净化后,用DB-1701毛细管色谱柱分离,火焰光度检测器(FPD)直接测定.在鱼、虾、贝类等样品中添加浓度为0.008×10-6、0.08 ×10-6和0.8×10-6的回收率(n=11)范围为72.6%～112%,相对标准偏差(RSD)为5.7%～9.0%,乐果、甲基对硫磷和马拉硫磷的检出限分别为0.002×10-6、0.002×10-6和0.004×10-6.本方法具有灵敏、快速、简便等特点,能满足海洋生物体中有机磷农残的监测要求.     

双毛细管柱气相色谱法测定环境水体中取代苯

本文使用 GDX- 10 2大孔树脂对水中微量烷基苯类、硝基苯类、卤代苯类进行了同时富集 ,富集后的水样用两根极性不同的毛细管柱进行气相色谱双柱定性 ,外标法定量。本方法对十四种取代苯的加标回收率为 92 %～ 98% ,相对标准偏差在 5 %以下 ,最低检测限达 3.2 5× 10 -9g。采用的双毛细管柱定性方法操作简便 ,结果可靠     

排污口有机污染物的GC/MS/AMDIS定性分析

采用自动质谱退卷积定性系统(AMDIS)分别对某排污口样品的气相色谱-质谱图进行了退卷积拆分处理,并调用拆分前后的谱图在NIST谱库中进行检索.结果发现,经过退卷积拆分处理以后,能够有效去除基体的干扰,其检索结果的准确性要明显高于人工解析检索结果.运用AMDIS从排污口样品中共检出包括酞酸酯类、氯代苯、苯胺、硝基苯、吲哚及其衍生物等43种有机污染物.     

气相色谱法测定水中甲萘威

通过改进预处理方法,采用带氮磷检测器的毛细柱气相色谱仪测定水中甲萘威的含量,得到了较好的精密度和准确度。     

海水中氯氟烃的气相色谱法测定

应用气相色谱法测定海水中氯氟烃,海水用Niskin采水器采集,将海水转移玻璃注射器中储藏直到分析。把大约30mL海水引入到一个玻璃气提器中,用高纯氮气将溶解在海水中氯氟烃(CFC's)吹扫出来浓缩在冷捕集器中,然后把捕集器加热,用高纯氮气CFC's送入气相色谱分离柱,CFC's由电子捕获检测器(ECD)检测出。结果表明:该方法快速,灵敏度高,分离效果好,适用于分析测定水体中氯氟烃。     

Fenton法去除微囊藻毒素及有机污染物的研究

利用Fenton法处理含有微囊藻毒素的湖水,经处理后的水样中微囊藻毒素去除率达到97．33％,CODMn、UV254、叶绿素a的去除率分别达到54．32％、32．22％和98．90％。在水样中投加10mg／L的聚合氯化铝,搅拌沉淀后水中残留总Fe低于GB5749--2006（生活饮用水卫生标准》限值。     

Kinetics of enhanced adsorption by polarization for organic pollutants on activated carbon fiber

The adsorption kinetics for model pollutants on activated carbon fiber (ACF) by polarization was investigated in this work. Kinetics data obtained for the adsorption of these model pollutants at open-circuit, 400 mV, and −400 mV polarization were applied to the Lagergren equation, and adsorption rate constants (K _a) were determined. With the anodic polarization of 400 mV, the capacity of sodium phenoxide was increased from 0.0083 mmol/g at open-circuit to 0.18 mmol/g, and a 17-fold enhancement was achieved; however, the capacity of p-nitrophenol was decreased from 2.93 mmol/g at open-circuit to 2.65 mmol/g. With the cathodal polarization of −400 mV, the capacity of aniline was improved from 3.60 mmol/g at open-circuit to 3.88 mmol/g; however, the capacity of sodium dodecylbenzene sulfonate was reduced from 2.20 mmol/g at open-circuit to 1.59 mmol/g. The enhancement for electrosorption changed with different groups substituting. Anodic polarization enhances the adsorption of benzene with the electron-donating group. But whether anodic or not, cathodal polarization had less effect on the adsorption of electron-accepting aromatic compounds, and decreased the adsorption capacity of benzene-bearing donor-conjugate bridge-acceptor, while increasing its adsorption rate. Electrostatic interaction played a very important role in the electrosorption of ion-pollutants. Translated from Environmental Science, 2006, 27(6): 1111–1116 [译自: 环境科学]     

柱前衍生吹扫捕集/气质联用法测定饮用水中的三氯乙醛

在碱性条件下,三氯乙醛转化为氯仿,通过测定加碱前后氯仿的差值间接求得三氯乙醛的含量。据此建立了吹扫捕集(PT)气相色谱质谱(GC/MS)测定饮用水中三氯乙醛的方法,方法检出限为0.05μg/L,回收率为94.0%~102.4%,相对标准偏差为3.6%~6.9%,方法简单快速,能满足饮用水分析要求。     

低温等离子体协同催化降解废气污染物的研究进展

阐述了低温等离子体协同催化工艺流程与反应机理,探讨了反应温度、废气进口组分、废气中水蒸气含量、气体流速、气溶胶等因素对降解效果的影响。分析认为:一段式低温等离子体协同催化可改变低温等离子体特征及催化剂催化特性,但尚未解决尾气臭氧逃逸、副产物产生及放电稳定性等问题;两段式低温等离子体协同催化可提高污染物分子降解效率并减少尾气臭氧逃逸,但未能有效利用等离子体的能量,气体中的水蒸气、粉尘及反应过程中产生的气溶胶均能影响后置催化剂的催化性能;两段式低温等离子体协同催化已具备工程应用条件,还需配套高效预处理单元以降低废气中水蒸气、粉尘等对催化剂的影响。     

工业废气中丙烯酸甲酯气相色谱法测定法

建立了用气相色谱法测定工业废气中丙烯酸甲酯的方法。废气中丙烯酸甲酯活性炭吸附,二硫化碳解吸,氢火焰离子化检测器检测,时间定性,峰面积定量。本方法前处理简便,分析灵敏度高,有机试剂使用量少,满足环境分析要求。     

流动注射在线氢化物发生-原子荧光光谱法测定环境水样中痕量无机汞和有机汞

提出了一种流动注射在线氢化物发生—原子荧光光谱法测定水样中痕量无机汞和有机汞的分析方法。以溴化剂作为有机汞的消解剂 ,在有、无溴化剂的存在下 ,采用流动注射在线氢化物发生—原子荧光光谱法分别测定总汞和无机汞 ,差减法求出有机汞的含量。方法操作简便快速 ,灵敏度高 ,干扰少 ,经加标回收实验验证 ,回收率达 95 %～ 10 5 %。     

生物膜填料塔降解有机废气的工业应用

工业应用研究表明 ,生物膜填料塔处理工业有机废气是可行的 ,处理后的废气能够达标排放。这一成果填补了我国环保工业技术领域的空白 ,工程技术上接近现阶段国外的技术研究水平     

离子色谱法测定水中总硬度

水质硬度的测定方法很多,本研究选用离子色谱法和EDTA络合滴定法对地下水和地表水样品分别进行测定,结果表明离子色谱法相对于传统的EDTA络合滴定法有干扰小,对环境污染少的优点,但水质测定的国标方法中没有该方法,因此建议可用离子色谱法测定水质硬度。