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Study on Cut Tobacco Drying Process Based on HS-GC/MS: Principal Component Analysis, Similarity Analysis, Drying Conditions, and Drying Mechanism. J CHEM-NY 2023. [DOI: 10.1155/2023/5772916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/09/2023] Open
Abstract
In order to study the volatile and semivolatile components changes of cut tobacco in the drying process, the cut tobacco were determined by headspace-gas chromatography/mass spectrometry (HS-GC/MS). Principal component analysis (PCA) and similarity analysis were used to analyze the HS-GC/MS results. Based on the similarity, the drying conditions and drying mechanism have been studied. The results showed that the increase in water content would reduce the dying rate, and if the temperature increased, the dying rate increased. The preliminary study on the drying kinetics of the drying process shows that Henderson and Pabis model appeared to be the most suitable for describing the drying process of cut tobacco, and the drying activation energy is 111.9 kJ.
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Liu M, Su Y, Guo Y. Headspace-Low Water Absorption Trap Technique: Analysis of Low-Abundance Volatile Compounds from Fresh Artemisia Annua L. with GC-MS. J Chromatogr Sci 2022; 60:907-915. [PMID: 34999777 DOI: 10.1093/chromsci/bmab143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 11/18/2021] [Accepted: 12/09/2021] [Indexed: 12/16/2022]
Abstract
Conventional headspace (HS) method could not meet the requirement of analyzing low-abundance volatile compounds in high water content samples. A HS-low water absorption trap technique coupled with gas chromatography-mass spectrometry was introduced to remove the large amount of water vapor; therefore, the low-abundance volatile compounds could be detected with better analytical sensitivity. With this method, a total of 81 volatile compounds were identified from fresh Artemisia annua L. by mass spectral library search, retention index and accurate mass measurement, which could make the qualitative results more accurate and reliable. These compounds belonged to different species, including terpene, cycloparaffin, aliphatic aldehyde, aromatic ketone, aromatic aldehyde and so on. The 2,5,6-trimethyl-1,3,6-heptatriene (8.23%) was the most principal compound, followed by γ-muurolene (6.80%), β-caryophyllenea (6.24%), 1,8-cineol (5.76%), 2-carene (5.65%), borneol (5.57%), isocaryophyllene (4.91%), bornylene (4.78%), camphene (4.30%) and β-pinene (4.26%) as the main components. The results indicated that this method presents a great potential for the trace analysis of volatile compounds in complex high water content samples.
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Affiliation(s)
- Mengpan Liu
- Shanghai University of Sport, 399 Changhai Road, Shanghai 200438, P.R. China
| | - Yue Su
- Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicine, 1200 Cailun Road, Shanghai 201203, P.R. China
| | - Yinlong Guo
- National Center for Organic Mass Spectrometry in Shanghai, Shanghai Institute of Organic Chemistry, Chinese Academy of Science, 345 Lingling Road, Shanghai 200032, P.R. China
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Modified layered bimetallic compound used as a novel adsorbent for the solid-phase extraction of monoaromatic hydrocarbons from water samples prior to gas chromatography–mass spectrometry. ARAB J CHEM 2020. [DOI: 10.1016/j.arabjc.2019.07.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Yang X, Wang C, Shao H, Zheng Q. Non-targeted screening and analysis of volatile organic compounds in drinking water by DLLME with GC-MS. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 694:133494. [PMID: 31398650 DOI: 10.1016/j.scitotenv.2019.07.300] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Revised: 07/18/2019] [Accepted: 07/18/2019] [Indexed: 06/10/2023]
Abstract
Volatile organic compounds (VOCs) in drinking water may potentially be hazardous. We developed a novel non-targeted analysis method of VOCs in drinking water that uses dispersive liquid-liquid microextraction coupled with gas chromatography-mass spectrometry. Analysis parameters were selected from range-finding tests on the peak number and average area of the extracted compounds. The optimized method was applied to analyze VOCs in tap water samples collected from Wuhan City, China. Twenty-seven compounds with high match degrees and a high prevalence were selected for quantification and evaluation. We used structure-activity relationships to predict the carcinogenicity of these compounds. Although most of the compounds were non-toxic, compounds such as dibutyl phthalate and diacetone alcohol should be investigated further. Untargeted analysis of the tap water samples identified 75-200 VOCs, including 67 highly prevalent compounds. Industrial and pharmaceutical chemicals accounted for approximately 70% of the VOCs in the samples. This method of non-targeted analysis and in silico toxicity prediction is simple and economic, and could be used in screening VOCs in drinking water.
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Affiliation(s)
- Xiaoqiu Yang
- Key Laboratory of Optoelectronic Chemical Materials and Devices of the Ministry of Education, School of Chemical and Environmental Engineering, Jianghan University, Wuhan 430056, PR China; Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), Department of Chemistry, Wuhan University, Wuhan 430072, PR China
| | - Chang Wang
- Hubei Key Laboratory of Environmental and Health Effects of Persistent Toxic Substances, Institute of Environment and Health, Jianghan University, Wuhan 430056, PR China
| | - Huancong Shao
- Key Laboratory of Optoelectronic Chemical Materials and Devices of the Ministry of Education, School of Chemical and Environmental Engineering, Jianghan University, Wuhan 430056, PR China
| | - Qi Zheng
- Key Laboratory of Optoelectronic Chemical Materials and Devices of the Ministry of Education, School of Chemical and Environmental Engineering, Jianghan University, Wuhan 430056, PR China.
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Ebrahimi R, Feizbakhsh A, Es’haghi A. Extraction and Derivatization of Chlorophenoxy Acid Pesticides: Performing Two DLLME with One Extracting Phase. Chromatographia 2016. [DOI: 10.1007/s10337-016-3042-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Rey-Salgueiro L, Omil B, Merino A, Martínez-Carballo E, Simal-Gándara J. Organic pollutants profiling of wood ashes from biomass power plants linked to the ash characteristics. THE SCIENCE OF THE TOTAL ENVIRONMENT 2016; 544:535-543. [PMID: 26674682 DOI: 10.1016/j.scitotenv.2015.11.134] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Revised: 11/03/2015] [Accepted: 11/25/2015] [Indexed: 06/05/2023]
Abstract
PURPOSE Wood ash, characterized by high content of certain nutrients and charcoal, can be applied to soils as a means of managing this waste product improving the soil quality. The associated environmental risk must be assessed. The objective of this study was to characterize the bottom and fly ash collected from 15 biomass power plants in Spain by determining the benzene, toluene, ethylbenzene, xylene and styrene (BTEX+S), PAHs and aliphatic hydrocarbon contents of both types of ash. Biochar was also used for comparison purposes. METHODS Gas chromatography-mass spectrometric methods were used for the identification and determination of both BTEX+S and aliphatic hydrocarbon contents in bottom and fly ashes, as well as biochar. High performance liquid chromatography with fluorescence detection was used for PAHs measurements. Multivariate correlation analysis was used to determine the relationship between sample characteristics and pollutants identified by partial least squares regression analysis. RESULTS AND DISCUSSION In general, the degree to which organic matter in the sample is burned increases with T50 or the "50% burn off" temperature (possibly due to the addition of fuel), and the BTEX+S also tended to increase. However, as the Q/MO (the heat of combustion divided by organic matter mass) increased, the combustion decreased or proceeded with less oxygen, which appears to be related to an increased presence of PAHs. The results confirm that the amounts of organic pollutants (PAHs and BTEX+S, together with total aliphatic hydrocarbons) in the wood ash do not exceed limits established for different soil or industrial uses. CONCLUSIONS Both types of ash, together with biochar, may therefore be suitable for application to soil as a fertilizer and an organic amendment, taking into account the target organic pollutants.
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Affiliation(s)
- Ledicia Rey-Salgueiro
- Nutrition and Bromatology Group, Department of Analytical and Food Chemistry, Food Science and Technology Faculty, University of Vigo - Ourense Campus, 32004 Ourense, Spain
| | - Beatriz Omil
- Sustainable Forest Management Unit, Department of Soil Science and Agricultural Chemistry, University of Santiago de Compostela - Lugo Campus, 27002 Lugo, Spain
| | - Agustín Merino
- Sustainable Forest Management Unit, Department of Soil Science and Agricultural Chemistry, University of Santiago de Compostela - Lugo Campus, 27002 Lugo, Spain
| | - Elena Martínez-Carballo
- Nutrition and Bromatology Group, Department of Analytical and Food Chemistry, Food Science and Technology Faculty, University of Vigo - Ourense Campus, 32004 Ourense, Spain
| | - Jesús Simal-Gándara
- Nutrition and Bromatology Group, Department of Analytical and Food Chemistry, Food Science and Technology Faculty, University of Vigo - Ourense Campus, 32004 Ourense, Spain.
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Applications of liquid-phase microextraction in the sample preparation of environmental solid samples. Molecules 2014; 19:6776-808. [PMID: 24858267 PMCID: PMC6271381 DOI: 10.3390/molecules19056776] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2014] [Revised: 05/19/2014] [Accepted: 05/21/2014] [Indexed: 11/17/2022] Open
Abstract
Solvent extraction remains one of the fundamental sample preparation techniques in the analysis of environmental solid samples, but organic solvents are toxic and environmentally harmful, therefore one of the possible greening directions is its miniaturization. The present review covers the relevant research from the field of application of microextraction to the sample preparation of environmental solid samples (soil, sediments, sewage sludge, dust etc.) published in the last decade. Several innovative liquid-phase microextraction (LPME) techniques that have emerged recently have also been applied as an aid in sample preparation of these samples: single-drop microextraction (SDME), hollow fiber-liquid phase microextraction (HF-LPME), dispersive liquid-liquid microextraction (DLLME). Besides the common organic solvents, surfactants and ionic liquids are also used. However, these techniques have to be combined with another technique to release the analytes from the solid sample into an aqueous solution. In the present review, the published methods were categorized into three groups: LPME in combination with a conventional solvent extraction; LPME in combination with an environmentally friendly extraction; LPME without previous extraction. The applicability of these approaches to the sample preparation for the determination of pollutants in solid environmental samples is discussed, with emphasis on their strengths, weak points and environmental impact.
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A versatile cryo-focussing flow switching gas chromatography inlet for trace analysis of intractable compounds. J Chromatogr A 2012; 1257:171-88. [DOI: 10.1016/j.chroma.2012.08.016] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2012] [Revised: 07/30/2012] [Accepted: 08/05/2012] [Indexed: 11/19/2022]
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Bernardo M, Lapa N, Gonçalves M, Mendes B, Pinto F, Fonseca I, Lopes H. Physico-chemical properties of chars obtained in the co-pyrolysis of waste mixtures. JOURNAL OF HAZARDOUS MATERIALS 2012; 219-220:196-202. [PMID: 22520075 DOI: 10.1016/j.jhazmat.2012.03.077] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2011] [Revised: 02/22/2012] [Accepted: 03/29/2012] [Indexed: 05/31/2023]
Abstract
The present work aims to perform a multistep upgrading of chars obtained in the co-pyrolysis of PE, PP and PS plastic wastes, pine biomass and used tires. The quality of the upgraded chars was evaluated by measuring some of their physico-chemical properties in order to assess their valorisation as adsorbents' precursors. The crude chars were submitted to a sequential solvent extraction with organic solvents of increasing polarity (hexane, mixture 1:1 v/v hexane:acetone and acetone) followed by an acidic demineralization procedure with 1M HCl solution. The results obtained showed that the upgrading treatment allow the recovery of 63-81% of the pyrolysis oils trapped in the crude chars and a reduction in the char's ash content in the range of 64-86%. The textural and adsorption properties of the upgraded chars were evaluated and the results indicate that the chars are mainly mesoporous and macroporous materials, with adsorption capacities in the range of 3.59-22.2 mg/g for the methylene blue dye. The upgrading treatment allowed to obtain carbonaceous materials with quality to be reused as adsorbents or as precursors for activated carbon.
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Affiliation(s)
- M Bernardo
- Unidade de Biotecnologia Ambiental, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Caparica, Portugal.
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Bernardo M, Gonçalves M, Lapa N, Barbosa R, Mendes B, Pinto F. Characterization of chars produced in the co-pyrolysis of different wastes: decontamination study. JOURNAL OF HAZARDOUS MATERIALS 2012; 207-208:28-35. [PMID: 21899951 DOI: 10.1016/j.jhazmat.2011.07.115] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2010] [Revised: 06/03/2011] [Accepted: 07/19/2011] [Indexed: 05/31/2023]
Abstract
The present work is devoted to the study of the decontamination of chars obtained in the co-pyrolysis of plastics, biomass and tyre wastes. The chars were extracted with several organic solvents of different polarities either individually or in sequence. The ability of each selected extractant to remove toxic pollutants was evaluated by comparing the extraction yields and by characterizing the crude extracts with a combination of chemical analysis and toxicity bioassays. Also, the mineral composition of the treated and non-treated chars was assessed. The results obtained in this study indicate that hexane is the more efficient extraction solvent to be used in the organic decontamination of chars obtained in the co-pyrolysis of plastics, tyres and biomass. A sequential extraction with solvents of increasing polarity can provide a better decontamination of the raw pyrolysis char than any individual extraction. The compounds removed from the char during the decontamination process are mainly aliphatic hydrocarbons and aromatic hydrocarbons, therefore a material that may be upgraded to be used as a fuel and/or as raw material for the organic chemical industry.
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Affiliation(s)
- M Bernardo
- Unidade de Biotecnologia Ambiental, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal.
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Diao CP, Wei CH, Feng CH. Rapid Determination of Benzene Derivatives in Water Samples by Trace Volume Solvent DLLME prior to GC-FID. Chromatographia 2012. [DOI: 10.1007/s10337-012-2215-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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12
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Herrera-Herrera AV, Asensio-Ramos M, Hernández-Borges J, Rodríguez-Delgado MÁ. Dispersive liquid-liquid microextraction for determination of organic analytes. Trends Analyt Chem 2010. [DOI: 10.1016/j.trac.2010.03.016] [Citation(s) in RCA: 197] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Bernardo M, Gonçalves M, Lapa N, Mendes B. Determination of alkylphenols in eluates from pyrolysis solid residues using dispersive liquid-liquid microextraction. CHEMOSPHERE 2010; 79:1026-1032. [PMID: 20416925 DOI: 10.1016/j.chemosphere.2010.03.062] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2009] [Revised: 03/30/2010] [Accepted: 03/31/2010] [Indexed: 05/29/2023]
Abstract
Dispersive liquid-liquid microextraction (DLLME) coupled with gas chromatography-mass spectrometry (GC-MS) was applied for the determination of 11 alkylphenols in eluates of chars produced in the co-pyrolysis of different wastes. The optimized DLLME procedure, 4 mL of sample solution, 15 microL of trichloroethylene as extraction solvent, 1 mL of acetone as dispersion solvent and addition of 15% (w/v) of NaCl, was validated. Under the optimum conditions, the enrichment factors were in the range of 82-180. Calibration curves were constructed for each analyte in pure water in the concentration range of 0.5-8 microg/L with correlation coefficients higher than 0.999. The limits of detection were between 0.07 and 0.17 microg/L. The repeatability of the method was evaluated using water samples fortified with the analyte mixture at two concentration levels: the relative standard deviation (RSD) values were between 3.7% and 8.0% for a concentration of 0.5 microg/L, and between 4.2% and 6.4% for a concentration of 3 microg/L. The recoveries of the analytes evaluated by fortification of real eluate samples were in the range of 67.9-97.9% for eluate 1 (obtained from a decontaminated char) and in the range of 61.9-101.4% for eluate 2 (obtained from the untreated char). o-Methylphenol presented low recoveries for both eluates showing a possible matrix effect. The results obtained show that this method is adequate for the determination of alkylphenols in environmental aqueous samples and presents itself as a fast and inexpensive technique, using minor amounts of organic solvents.
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Affiliation(s)
- M Bernardo
- Unidade de Biotecnologia Ambiental (UBia), Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Caparica, Portugal.
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