水中痕量有机污染物质富集技术的发展──聚氨酯类泡沫富集回收水中的多环芳烃

用聚氨酯类泡沫（PUF）富集回收蒸馏水、自来水与河水中的多环芳烃，方法简便，回收率高，适于现场采集各种不同类型的水样．GC／MS分析中，氘化芘在IL蒸馏水中的检出限为26ng／L；而在HPLC／FLD分析中，苯并（k）荧蒽、苯并（a）芘、二苯并（a，h）蒽、苯并（ghi）在IL蒸馏水中的检出限分别为0.86、0.51、2.1和3.0ng／L.     

水中痕量有机污染物质富集技术的发展——聚氨酯类泡沫富…

用聚氨酯类泡沫（ＰＵＦ）富集回收蒸馏水，自来水与河水中的多环芳烃，方法简便，回收率高，适于现场采集各种不同类型的水样，ＧＣ／ＭＳ分析中，氚化芘在１Ｌ蒸馏水中检出限为２６ｎｇ／Ｌ，而在ＨＰＬＣ／ＦＬＤ分析中，苯并（ｋ）荧蒽，苯并（ａ）芘，二苯并（ａ，ｈ）蒽，苯并（ｇｈｉ）在１Ｌ蒸馏水中的检出限分别为０．８６，０．５１，２．１和３．０ｎｇ／Ｌ。     

使用C18固要萃取膜—色质联用定量分析饮用水中痕量多环芳烃的初步 …

参照美国ＥＰＡ５２５．１方法,Ｃ１８－固相萃取膜萃取饮用水中的有机物,利用ＧＣ／ＭＳ法鉴定多环芳烃（ＰＡＨＳ）,使用１６种多环芳烃混合标准样绘制标准曲线,以内标法对ＰＡＨＳ进行定量分析。采用本方法某水厂经过深度处理后的出厂水中的７种多环芳烃的含量,ＰＡＨＳ的平均回收率为９４．０－９７．７％。检测限为０．００１μｇ／Ｌ。     

用固相萃取技术富集水中多环芳烃

系统地研究了淋洗剂强度、用量和有机改性剂的加入对固相萃取水中多环芳烃回收率的影响。研究表明,二氯甲烷和苯的洗脱效果较好,回收率为８７％～１０２％;当淋洗剂的用量超过１．５ｍＬ时,对多环芳烃的回收率没有明显的影响;向自来水样中加入２０％有机改性剂可明显改善多环芳烃的回收效果,使回收率达到８９％～１０８％。     

固相微萃取-气相色谱-质谱联用测定海水和沉积物间隙水中的痕量多环芳烃

建立了固相微萃取(SPME)与气相色谱-质谱(GC-MS)联用同时测定海水中16种多环芳烃的分析方法, 研究了萃取时间、盐度条件的影响. 同时用SPME的方法研究了海水中的溶解有机物(DOM)对多环芳烃萃取的影响. 计算出不同DOM浓度下多环芳烃K_DOM与K_OW的关系: C_DOM=5 mg/L时, logK_DOM = 0.7944K_OW + 0.773 (R² = 0.91). C_DOM=10 mg/L时, logK_DOM = 0.7905K_OW + 0.668 (R² = 0.97); C_DOM=30 mg/L时, logK_DOM = 0.714K_OW + 1.0407(R² = 0.91). 该法对16种多环芳烃的检出限为0.1~3.5 ng/L, 相对标准偏差(RSD, n=5)为 4%~23%. 用该法分析海洋环境中的痕量多环芳烃, 16种多环芳烃的平均回收率为88.2±20.4%, 方法快速、灵敏、简单, 适用于快速分析海水和沉积物间隙水样中的痕量多环芳烃.     

非平衡体系中固相微萃取技术的定量分析研究--快速监测水中痕量的有机污染物(多环芳烃)

采用固相微萃取技术,以100μm膜厚的聚二甲基硅氧烷纤维萃取水中10种多环芳烃,在60min采样时间内纤维上的吸附量与采样的时间近乎成正比,分配体系达到平衡前可以定量地测定水中的待测物.该方法的线性范围在0.1～100μg/L,检出限在0.01～0.03μg/L,15μg/L的回收率在80%～100%,相对标准偏差在20%以下.     

固相萃取-气相色谱串联质谱法测定饮用水中的多环芳烃和邻苯二甲酸酯

采用固相萃取、中性硅胶-中性氧化铝复合柱对水样进行提取和净化,采用气相色谱串联质谱法测定水样中的16种多环芳烃和6种邻苯二甲酸酯.该方法对水样中的多环芳烃和邻苯二甲酸酯的检测限分别为0.10～0.26 ng/L和0.20～2.0 ng/L,加标回收率分别在88.6％～111.7％和85.3％～110.5％之间,样品重复测定6次,相对标准偏差(RSD)均小于15％.实验结果表明,该方法灵敏度高、重复性好、定量准确,可用于饮用水中多环芳烃和邻苯二甲酸酯的测定.     

用自制新型端羟基冠醚固相微萃取涂层快速监测水中痕量多环芳烃

采用溶胶—凝胶技术，加入自制的新化合物端羟基冠酸，成功地涂制了固相微萃取涂层；用半挥发性的有机污染物多环芳烃评价了涂层的基本性能，并对实际水样中的多环芳烃进行了分析。该方法的线性范围在0．1—10μg／L，检出限在0．001—0.03μg/L，8种多环芳烃化合物测定的相对标准偏差在2．05％一9．80％，回收率在85％以上。     

固相微萃取-高效液相色谱联用分析环境水样中的痕量多环芳烃

建立了固相微萃取(SPME)-高效液相色谱(HPLC)联用同时测定环境水样中8种多环芳烃的分析方法。优化了萃取时间、萃取温度、解吸时间、解吸溶液、解吸模式等条件。该法对8种多环芳烃的检出限为0.002-0.180 μg/L,相对标准偏差(RSD, n=6)为4.4%-12.2%。用该法分析江水中的痕量多环芳烃,除苯并［b］荧蒽外,其他7种多环芳烃的回收率为91.1%-115.8%,RSD(n=3)为3.6%-18.8%。方法快速、灵敏、简单,适用于快速分析环境水样中的痕量多环芳烃。     

Solid-phase extraction clean-up procedure for the analysis of PAHs in lichens

A clean-up procedure based on a solid-phase extraction column was optimized for determination of polycyclic aromatic hydrocarbons (PAHs) in lichen extracts to remove co-extracted compounds from the matrix in the final extract. Several kinds of solid phases were evaluated: normal phase (-NH₂ and alumina), strong anion exchange and reversed phase. The -NH₂ columns were the most effective by using a packed solid bed of 500?mg. The lichen raw extract was loaded on the column previously conditioned with dichloromethane and hexane. Hexane (0.5?mL) was used as rinsing solvent, and PAHs were quantitatively eluted (80–97%) using 2?mL of hexane–dichloromethane (65–35) as eluting solvent. In these conditions, even the heaviest PAHs were quantitatively eluted. The optimized SPE method provides a short time and low-solvent-consumption sample clean-up compared with other conventional methods based on column chromatography. The analytical procedure, dynamic sonication-assisted extraction, followed by the optimized solid-phase extraction clean-up, was used to determine the 16 EPA priority PAHs from native lichens collected from the Aragon valley in central Pyrenees. The PAH concentrations in lichen samples ranged from 352 to 1654?ng?g^?1, and the minimum concentration value was established as the regional reference PAH levels in the area.     

多种电极的SPE水电解性能研究

研究了IrRu/Nafion117/PbAg、IrRu/Nafion117/Ni、IrRu/Nafion117/TiNi、Ag/Nafion117/Ni、C/Na-fion117/PtRu等5种三合一膜电极(MEA)的水电解性能.实验发现,上述各电极的阳极活性顺序为:IrRu>Ag>C,阴极为:Ni>PbAg>TiNi,TiNi的稳定性比Ni好很多,PbAg最为稳定.各电极的过电位均随温度的升高而下降,电流效率随电流密度的增大而提高.     

气浮浮选分离富集-紫外分光光度法测定水中痕量强力霉素

水样中痕量的强力霉素(DXCC)用正丙醇及无水乙醇(4+1)作混合溶剂,从pH 8的溶液中进行气浮浮选使之分离并富集.加入氯化钠作为分相剂,加入铁(HI)使与DXCC反应生成憎水的络合物而浮选入有机相,在383 am波长处测定有机相的吸光度.吸光度与DXCC浓度在3.1×10-7～2.0×10-5mol·L-1范围内呈线性关系,方法的检出限(3S/N)为2.6×10-7mol·L-1,测定中采用自制的气浮浮选装置.应用所提出的方法分析了3种不同来源的水样,并以此样品作为基体用标准加入法对方法的回收率进行了测定,测得方法的平均回收率为99.7%,测定值的相对标准偏差(n=5)均小于2.5%.     

活性炭富集-电热塞曼原子吸收光谱法测定水中痕量的汞

建立了一种水中痕量汞的测定方法。通过活性炭定量吸附水中痕量汞,采用电热塞曼原子吸收光谱法测定活性炭富集的汞。与目前水中总汞测定方法相比,本方法避免了消解等步骤,减少了汞污染和汞损失,操作更加简单。考察了活性炭粒度、酸处理方法、酸介质和富集时间对富集效率的影响,以及热解温度和干扰离子对方法测定结果的影响。通过空白活性炭加标、空白溶液加标和环境水样加标3种方法制作标准曲线,三者的相关系数达0.9999,经统计检验,3条标准曲线的斜率无差异,表明了在此实验条件下环境水样中的共存物不干扰汞的测定,同时也表明可直接用空白活性炭加标的方法进行标准曲线的绘制。采用本方法对含5和50 ng/L汞的水样进行测定,其相对标准偏差分别为7.2%和4.2%(n=11)。本方法测定下限达到1.2 ng/L。地表水和自来水样中添加10 ng/L汞的加标回收率在92.0%~103.0%之间。用 ICP-MS作对照,二者分析结果相符合,相对误差在2.9%~ 3.4%之间,表明本方法准确可靠、精密度好。     

Optimization of An On-Line Precolumn Preconcentration Method for the Determination of Polycyclic Aromatic Hydrocarbons (PAHs) in Water Samples (River and Sea Water)

Abstract

A new on-line precolumn preconcentration method for the determination of EPA priority pollutants (PAHs) in river and sea water has been developed. The retention time for each PAH in the precolumn has been determined for several percentages of organic solvent (acetonitrile) in the sample. This is very important because recoveries show a great dependence on this parameter.

The proposed procedure, combined with HPLC and spectrofluorimetric detection, reaches very low detection limits (subnanograms per liter) and it has been applied to river and sea water samples with good results.     

固相萃取-高效液相色谱法测定水中呋喃丹

取200mL水样,流经C_(18)固相萃取(SPE)小柱富集呋喃丹。用5.0mL四氢呋喃从SPE柱上洗脱呋喃丹,收集洗脱液,在35℃吹氩蒸干。用1.0mL甲醇溶解残渣,所得溶液供高效液相色谱分析。用Eclipse XDB C_(18)色谱柱及由甲醇-水(1+1)混合溶液作流动相进行分离,并以285nm作激发波长,320nm作发射波长对呋喃丹作荧光检测。测得呋喃丹的质量浓度在5.0×10~(-4)～5.0mg·L~(-1)范围内与相应的峰面积值呈线性关系,检出限(3S/N)为0.02μg·L~(-1)。以水样为基体加入3个浓度水平(1.0,50.0,200.0μg·L~(-1))标准溶液对方法作回收及精密度试验,测得回收率在94.0%～99.6%之间,相对标准偏差(n=7)在1.2%～4.2%之间。     

Multiresidue Analysis of Organic Pollutants in Water by SPE with a C8 and SDVB Combined Cartridge

Abstract

A multi-component target method for screening purposes to determine organic pollutants of different polarities in water is reported. The following classes of chemicals were tested: base-neutral and acidic herbicides, phenolic compounds, polycyclic aromatic hydrocarbons and phthalic acid esters.

Data was initially obtained from the extraction of one liter of water sample, using separate octyl bonded porous silica (C8) and highly crosslinked polystyrene based polymer columns (SDVB) cartridges. A second set of data was obtained using for the extraction a combined cartridge containing both phases. The analysis was carried out directly by GC-MS in SIM mode, without any derivatisation, with the exception of acidic herbicides, derivatised with pentafluorobenzylbromide. The obtained results showed recoveries between 75% and 98% at two different spiking levels, with relative standard deviations below 15%.     

气相色谱-质谱法测定含油污泥中16种多环芳烃

采用超声提取和固相萃取小柱净化的前处理方法,结合气相色谱-质谱法(GCMS),建立了含油污泥中16种多环芳烃的检测方法。以新疆的油田采油或钻井等过程中产生的含油污泥为样品,经超声提取,固相萃取(SPE)小柱除杂净化后,用GC-MS法进行定量分析。16种多环芳烃在0.005~0.200mg/L范围内线性关系良好,相关系数为0.998~0.999,检出限(S/N=3)在0.26~2.38μg/kg之间,以0.200、0.500和1.000mg/L添加浓度水平进行方法学验证,回收率在60.20%~149.66%范围内,相对标准偏差为3.37%~16.84%。该方法具有快速、简便、灵敏度高等特点,能满足含油污泥中16种多环芳烃的检测要求。     

Continuous Determination of Trace Amounts of Humic Acid in Natural Water by Chemiluminescence Method

A chemiluminescence (CL) method for the determination of humic acid (HA) based on the oxidation of HA with hydrogen peroxide in the presence of formaldehyde in alkaline solution is described. This method is sensitive and selective for the determination of HA in natural water. HA produces strong CL in the oxidation of HA with MnO₄⁻, Br₂, ClO⁻, and Cr₂O₇²⁻, and the H₂O₂. HA-H₂O₂-HCHO system is suitable for the determination of HA because of its high sensitivity and high selectivity. The detection limit was 50 ppb and relative standard deviation for five measurements of 0.5 ppm (w/w) HA was 1.8%. Cations such as Na⁺, K⁺, Mg²⁺, Cu²⁺, and Fe3⁺ and anions such as PO₄³⁻, NO₃⁻, CO₃²⁻, SO₄²⁻, Cl⁻, and Y⁻ (EDTA-Na) did not interfere with the determination of HA. Addition of Mn(II) increased the CL intensity. The concentration of HA in natural water determined with this method is in good agreement with that determined by fluorometric analysis.