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21.
Herbert P Silva AL João MJ Santos L Alves A 《Analytical and bioanalytical chemistry》2006,386(2):324-331
The present work was focused on the development of a simple method aimed at the determination of 12 polycyclic aromatic hydrocarbons
(PAHs) and 15 polychlorinated biphenyls (PCBs) in landfill leachates and sediments by adapting a domestic microwave oven to
perform microwave-assisted headspace solid-phase microextraction (MA-HS-SPME) followed by gas chromatographic separation and
tandem mass spectrometric detection. Good linearity was observed within the concentration range studied; detection limits
ranged from 0.1 ng/l to 7 ng/l for PCBs and from 5 ng/l to 926 ng/l for PAHs. Concerning precision, the relative standard
deviations obtained were, on average for the leachate and sediment samples analysed, 18% for PCBs and 20% for PAHs. Average
recovery values were 37% and 76% for PCBs, and 58% and 48% for PAHs, respectively, for the leachate and reference sediment
studied. The method allows the determination of PAHs and PCBs in landfill leachates and sediments, avoiding clean-up steps
and the consumption of organic solvents. 相似文献
22.
Staffan Bergström Britt-Marie Svensson Lennart Mårtensson Lennart Mathiasson 《International journal of environmental analytical chemistry》2013,93(1):1-15
A strategy is presented for evaluation of treatment procedures for landfill leachate with emphasis on organic pollutants. An analytical scheme, the LAQUA protocol, was developed as a guide for the analytical work. The protocol includes organic as well as metals, inorganic ions, water-quality parameters, and toxicity. The proposed strategy considers the behaviour of both polar and non-polar organic substances at trace levels. For polar substances, phenols were chosen as markers and determined with an automated supported liquid membrane extraction device, coupled on-line to HPLC with a diode-array detector. For non-polar substances, PCBs and 10 unidentified compounds were chosen as markers and analysed by solid-phase extraction combined with supercritical fluid extraction with GC analysis. The chosen measurement strategy, based on the use of marker substances, difference measurements, and versatile data-handling procedures, provided essential information about complex systems at relatively low cost. 相似文献
23.
Paulina Palma Raúl Calderón Marcelo Godoy María A. Rubio 《International journal of environmental analytical chemistry》2016,96(7):627-635
Two analytical methods as inductively coupled plasma optical emission spectrometry (inductively coupled plasma optical emission spectroscopy (ICP-OES)) and azomethine-H UV-Vis-based method were compared statistically, to evaluate their analytical characteristics and applicability to the determination of boron in leachates (complex matrix) from sanitary landfills (SLs) and groundwater (simple matrix) from different sampling points near SLs. Calibration curves and standard addition methods were used for this purpose. Azomethine-H UV-Vis-based procedure has proven better precision and accuracy than ICP-OES. However, statistical analysis (F-test and t-test) does not show significant differences between these two methods, achieving concentration range of up to 10 mg L?1 of the boron in both simple and complex matrices. Due to low cost and gentle-to-operate easy-accessible system, the azomethine-H UV-Vis-based method was therefore proposed (rather than ICP-OES) for routine analysis and for feasible on-site monitoring of boron in SLs, with respect to satisfy Chilean Standard 409 (NCh409) related to drinking water policy. 相似文献
24.
25.
S. Thorburn B. A. Colenutt S. G. Douglas 《International journal of environmental analytical chemistry》2013,93(3):245-254
Abstract The safe development of landfill sites is daily increasing in importance. In this context the analysis of soil gases. especially for methane. is vital. Techniques have been developed for the sampling of such gases. and their subsequent analysis at the v.p.m. level by gas chromatography. Factors affecting the gas concentrations are considered. 相似文献
26.
Suwannee Junyapoon Keith Bartle Andrew Ross Michael Cooke 《International journal of environmental analytical chemistry》2013,93(2):47-59
Volatile compounds containing Group V and Group VI elements in landfill gases are of concern as a source of toxic pollutants and unpleasant odors. Conventional analytical techniques for these compounds e.g. ICP-MS, ICP-AES are complicated, expensive and time consuming. The use of a simple programmed temperature vaporization injection (PTV) technique coupled to gas chromatography with atomic emission detection (GC-AED) has been successfully demonstrated to identify compounds containing arsenic, antimony, and sulfur in landfill gas. With an adapted PTV injection system (using a combination of a ten-port and a six-port Valco valves), problems associated with AED discharge tube damage due to high carrier gas flow rate during sample loading can be overcome. The gas samples generated from both a laboratory biowaste digester and a domestic landfill site were characterized using these techniques. Large sample gas volumes were adsorbed onto a cooled sorbent trap containing Porapak Q, followed by rapid liberation onto a porous layer open tubular column (PLOT) using programmed thermal desorption. Arsenic and antimony were also detected in the landfill leachate collected from the same landfill site using hydride generation-atomic absorption spectrometry (Hy-AAS). The efficiency of different traps has also been compared. 相似文献
27.
Luis Jiménez Roberto Alzaga Josep M. Bayona 《International journal of environmental analytical chemistry》2013,93(7):415-430
Leachates derived from landfills constitute a potential risk of groundwater pollution because a variety of contaminants can be released by leaking from the contention system. Therefore, the leachate composition is of interest of their appropriate management. Although the leachate characterisation is usually carried out by global parameters (i.e. DOC, BOD, COD, AOX, etc), its characterisation at molecular level is of increasing interest and will be reviewed in the present article. Sample handling and determination techniques for a variety of organic contaminants is discussed and pitfalls as well as limitations of each analytical technique will be highlighted. 相似文献
28.
Samples of polyethylene (PE) and polypropylene (PP) with 2% Renatura™ pro-oxidant additive were subjected to varying times of weathering (UVCON; ISO 4892-3), transferred to dark thermal exposure (at 70 °C) and the subsequent degradation monitored by measuring elongation at break and tensile strength during intervals up to 45 days. The results demonstrate that the oxidative degradation, after initial light exposure, continues more rapidly in the dark thermal conditions and that increased exposure to light increases thermal oxidative degradation. 相似文献
29.
Yamamoto A Yasuhara A Kodama S Matsunaga A Suzuki S Mohri S Yamada M 《Journal of separation science》2004,27(4):325-329
An ion-exclusion chromatographic method with on-line desalinization for the determination of volatile fatty acids in landfill leachates is described. Highly sensitive conductivity detection of the organic acids was achieved by using dilute p-hydroxybenzoic acid solution as an eluent. Interference with mineral acids was reduced by treatment with barium chloride solution prior to desalinization. A silver-loaded cation-exchange guard column for the desalinization was installed in series with the analytical column to avoid the contamination of organic acids. This method features detection limits of 0.01 mg L(-1) formic acid, 0.02 mg L(-1) acetic acid, 0.05 mg L(-1) propionic acid, and 0.1 mg L(-1) butyric acid, respectively, with an injection of 20 microL sample. Application of the on-line desalinization LC method is illustrated for leachate samples from a Japanese sanitary landfill. 相似文献
30.
Application of activated carbon in the characterization of nitrogen compounds and phthalates in a landfill leachate 总被引:1,自引:0,他引:1
Lisiane dos Santos Freitas 《Microchemical Journal》2004,78(1):61-64
The goal of this work was the development of a methodology based on solid phase extraction (SPE) to characterize nitrogen compounds and phthalates from landfill leachate samples. Activated carbon (AC) was used to extract all the organic compounds from the samples. The samples were collected in Porto Alegre-South Brazil. As the AC used had small particle size, it was impossible to use it in the form of packed cartridges; hence, it had to be applied in a batch mode. The desorption of the organic compounds from the AC was made by sonication with dichloromethane. The extract was analyzed by gas chromatography with mass spectrometric detection (GC-MSD). Some aspects of the validation of the methodology were also established. Several nitrogen compounds and phthalates were identified in the samples, proving the efficiency of this method with regard to the selectiveness for these substances. 相似文献