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1.
J Environ Manage ; 361: 121241, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38805962

RESUMO

According to the latest reports, estimated values of 50,000-66 000 t of end-of-life wind turbine blades (WTB) are expected to be decommissioned in Europe in 2025-2030, posing a significant threat from the environmental and waste management perspectives. This study aims to present the preliminary Life Cycle Assessment (LCA) with sensitivity and uncertainty analysis of the lab-scale oxidative liquefaction process of the WTB, as the original method to recover the high-quality glass fibers with simultaneous production of the secondary chemicals: phenols, ketones, acids, and fatty acids, from the oxidation of the epoxy resin from the polymer matrix. The LCA is based on the experimental results of the oxidative liquefaction process carried out on a laboratory scale using a Parr 500 ml batch reactor, at two different conditions sets for the functional unit (FU) of 1 kg of treated WTB. Each of the analyzed scenarios resulted in higher impact indicators compared to the landfilling. The highest quality fibers were obtained at 350 °C and 40 wt % H2O2 content resulted in 5.52 ± 1.20 kgCO2 eq Climate change impact and 97.8 ± 20.6 MJ of Resource use, fossil per kg of recycled WTB. The lowest quality fiber recovered in char, yet well separated from the matrix obtained at 250 °C and the lowest H2O2 content resulted in 0.0953 ± 0.487 kgCO2 eq Climate change impact and 8.84 ± 7.90 MJ of Resource use, fossil per kg of recycled WTB. The hot spot and sensitivity analysis indicated, that the oxidizer for the process - hydrogen peroxide, when acquired as a shelf product causes a significant burden on the whole process, with sensitivity ratios on the total impact indicators varying across the categories from 0.56 to 0.99. Substitution of H2O2 with theoretical 0-input oxidizer allowed to significantly lower environmental load of the recycling process, which in all of the analyzed scenarios presented environmental benefits compared to landfilling with recovery of the glass fiber and secondary chemicals.


Assuntos
Reciclagem , Gerenciamento de Resíduos/métodos , Vento , Oxirredução , Peróxido de Hidrogênio/química
2.
ACS Omega ; 9(5): 5966-5971, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38343973

RESUMO

In the following research, a new modification of traditional atom pairs is studied. The atom pairs are enriched with values originating from quantum chemistry calculations. A random forest machine learning algorithm is applied to model 10 different properties and biological activities based on different molecular representations, and it is evaluated via repeated cross-validation. The predictive power of modified atom pairs, quantum atom pairs, are compared to the predictive powers of traditional molecular representations known and widely applied in cheminformatics. The root mean squared error (RMSE), R2, area under the receiver operating characteristic curve (AUC) and balanced accuracy were used to evaluate the predictive power of the applied molecular representations. Research has shown that while performing regression tasks, quantum atom pairs provide better fits to the data than do their precursors.

3.
J Mol Graph Model ; 125: 108584, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37611341

RESUMO

The aim of the following research is to assess the applicability of calculated quantum properties of molecular fragments as molecular descriptors in machine learning classification task. The research is based on bio-concentration and QM9-extended databases. A number of compounds with results from quantum-chemical calculations conducted with Psi4 quantum chemistry package was also added to the quantum properties database. Classification results are compared with a baseline of random guesses and predictions obtained with the traditional RDKit generated molecular descriptors. Chosen classification metrics show that results obtained with fragments quantum descriptors fall between results from baseline and those provided by molecular descriptors widely applied in cheminformatics. According to the results, the implementation of principal component analysis, causes a drop in categorization metrics.


Assuntos
Quimioinformática , Aprendizado de Máquina , Bioacumulação , Bases de Dados Factuais , Análise de Componente Principal
4.
Sci Rep ; 13(1): 9270, 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37286809

RESUMO

Wind energy has significant growth potential and applicability on a global scale, but approximately 2.4% of wind turbine blades must be decommissioned annually. The majority of blade components can be recycled; however, wind blades are rarely recycled. In the present study, an alternative method was presented involving a small molecule-assisted technique based on a dynamic reaction that dissolves waste composite materials containing ester groups to recycle end-of-life wind turbine blades. This effective process requires temperatures below 200 °C, and the major component, i.e., resin, can be easily dissolved. This method can be applied to recycle composite materials, such as wind turbine blades and carbon fibre composites comprising fibres and resins. Depending on the waste, up to 100% of the resin degradation yield can be achieved. The solution used for the recycling process may be reused multiple times and can be reused to obtain resin-based components and create a closed loop for this type of material.

5.
Materials (Basel) ; 14(4)2021 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-33562112

RESUMO

In this paper, various graphite oxide (GO) and reduced graphene oxide (rGO) preparation methods are analyzed. The obtained materials differed in their properties, including (among others) their oxygen contents. The chemical and structural properties of graphite, graphite oxides, and reduced graphene oxides were previously investigated using Raman spectroscopy (RS), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD). In this paper, hierarchical clustering analysis (HCA) and analysis of variance (ANOVA) were used to trace the directions of changes of the selected parameters relative to a preparation method of such oxides. We showed that the oxidation methods affected the physicochemical properties of the final products. The aim of the research was the statistical analysis of the selected properties in order to use this information to design graphene oxide materials with properties relevant for specific applications (i.e., in gas sensors).

6.
J Environ Manage ; 281: 111787, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33385899

RESUMO

The emission of pollutants into the air during the combustion of solid fuels in households is still a significant problem in many European Union countries, including Poland. These emissions are a significant source of many air pollutants formed during incomplete combustion and has been identified as one of the leading environmental risk factors for these populations. One of the solutions is to utilise thermally processed solid fuels. This article discusses the concentrations of pollutants emitted as a result of the combustion of conventional fuels and new low-emission fuel in out-of-class heaters. To gain better insight into the relationships between fuel type and flue gas quality, chemometric methods and variance analysis were used. Principal component analysis confirmed that the fuel type significantly influences the level of dust emissions and the total organic carbon and sum of polycyclic aromatic hydrocarbons in the dust. Clustering analysis identified how the concentrations of polycyclic aromatic hydrocarbons correlate with the amounts of dust and total organic carbon and showed that this correlation is proportional to the size of the molecule and consequently the number of aromatic rings. The use of low-emission fuel as a solid fuel in households, as our analyses have shown, can reduce the concentrations of dust, total organic carbon and polycyclic aromatic hydrocarbons by up to 50 times, thereby reducing air pollutants in cities.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Cidades , Carvão Mineral , Monitoramento Ambiental , Polônia , Hidrocarbonetos Policíclicos Aromáticos/análise
7.
Food Chem ; 335: 127658, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32731124

RESUMO

Raphanus sativus var. longipinnatus, was exposed under experimental conditions to herbicides: rimsulfuron (RIM), administrated as (1) pure substance, (2) in commercially available formulation (RIMEL), (3) its degradation product: 4,6-dimethoxypyrimidin-2-amine (2ADP), (4) mesotrione (MES), (5) sulcotrione (SUL). Profiling and fingerprinting strategies, conducted by LC-MS/MS-FL, were employed to find markers of plant exposure to herbicide stress. The presence ofRIM metabolite in the tissues of plant exposed to this herbicide proved that it is necessary to determine both parent compound and its by-products to obtain reliable information on plant exposure to agrochemicals. A higher content of normetanephrine (NMN) (18-175%) and lower content of tyramine (TYR) (49-75%) and epinephrine (E) (75-83%) was observed in plant tissues exposed to RIM and 2ADP in comparison to blank sample. Therefore, NMN, TRY and E may be considered as markers of plant response to RIM. Non-target analysis enables to recognize the type of herbicide used during cultivation.


Assuntos
Herbicidas/toxicidade , Resíduos de Praguicidas/análise , Piridinas/toxicidade , Raphanus/química , Raphanus/efeitos dos fármacos , Sulfonamidas/toxicidade , Cromatografia Líquida , Cicloexanonas/farmacocinética , Cicloexanonas/toxicidade , Biomarcadores Ambientais , Epinefrina/análise , Mesilatos/farmacocinética , Mesilatos/toxicidade , Metaboloma , Normetanefrina/análise , Plantas Comestíveis/química , Plantas Comestíveis/efeitos dos fármacos , Piridinas/farmacocinética , Pirimidinas/toxicidade , Raphanus/metabolismo , Sulfonamidas/farmacocinética , Espectrometria de Massas em Tandem , Tiramina/análise
8.
J Chromatogr Sci ; 58(9): 831-843, 2020 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-32869054

RESUMO

The program of potato protection recommended by the producers of agrochemicals requires application: thiamethoxam, lambda-cyhalothrin, deltamethrin, rimsulfuron and metalaxyl. Therefore, there is a risk that these pesticides are present in tubers, thus posing a toxicological risk to the consumer. In this respect, it is necessary to monitor the presence of these compounds in edible plants. Therefore, the aim of this paper was to develop a novel, simple and robust analytical procedure for simultaneous determination of above-mentioned pesticides in potato tubers. To develop an analytical procedure that fulfills SANTE demands, quick, easy, cheap, effective, rugged and safe method and matrix solid phase dispersion technique were investigated. The final determination was conducted by liquid chromatography with tandem mass spectrometry. The obtained experimental data were analyzed by analysis of variance. For the extraction of analytes, matrix solid phase dispersion with octadecyl sorbent and methanol as eluent was chosen, since it provides the validation parameters according to SANTE requirements (recovery: 77-111%, relative standard deviation: 1-10%, limit of quantification: 0.9-5.0 µg/kg). This innovative analytical procedure is a practical analytical tool, which was successfully proven by applying it for target pesticides determination in potato tuber samples of different varieties randomly chosen at local markets.


Assuntos
Cromatografia Líquida/métodos , Praguicidas/análise , Tubérculos/química , Solanum tuberosum/química , Espectrometria de Massas em Tandem/métodos , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos Testes
9.
Crit Rev Anal Chem ; 48(6): 467-491, 2018 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-29621408

RESUMO

The aim of this article is to present the trends in extraction techniques applied for the isolation of pesticides from plant matrix. To fully compare the effectiveness of different extraction techniques, it was required to analyze compounds with possibly wide spectrum of physicochemical properties. Hence, compounds representing neonicotinoids, pyrethroids, sulfonylureas and phenylamides were selected. Based on literature studies, it may be concluded that there are three main approaches to make the analytical procedures for pesticides determination more effective: (i) the optimization of extraction conditions, however, according to ANOVA conducted on the collected literature data, not all parameters influence the extraction process equally; chemometric studies based on literature reports may lead to the conclusion that the most favorable conditions (criterion: analyte recovery, repeatability) for neonicotinoid, pyrethroid and sulfonylurea herbicide extraction from plant tissues are provided by QuEChERS - extraction with acetonitrile, while the mixtures of PSA and GCB (for neonicotinoids), and PSA, GCB, C18 (for pyrethroids) should be used in d-SPE step. For sulfonylurea compounds and metalaxyl it was impossible to identify a sorbent(s) that cleans up the extract more effectively than the others; (ii) to develop a new generation of sorbents; however, the range of their applicability is limited, mainly due to difficulties in their synthesis; (iii) to develop the new extraction techniques with as few "trouble spots" as possible.


Assuntos
Extração Líquido-Líquido , Praguicidas/análise , Plantas/química , Extração em Fase Sólida
10.
Environ Sci Pollut Res Int ; 24(1): 644-658, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27743329

RESUMO

The aim of this study was to monitor the sediment, soil and surface water contamination with selected popular triketone herbicides (mesotrione (MES) and sulcotrione(SUL)), atrazine (ATR) classified as a possible carcinogen and endocrine disrupting chemical, as well as their degradation products, in Silesia (Poland). Seventeen sediment samples, 24 soil samples, and 64 surface water samples collected in 2014 were studied. After solid-liquid extraction (SLE) and solid phase extraction (SPE), analytes were determined by high-performance liquid chromatography (HPLC) with diode array detection (DAD). Ten years after the withdrawal from the use, ATR was not detected in any of the collected samples; however, its degradation products are still present in 41 % of sediment, 71 % of soil, and 8 % of surface water samples. SUL was determined in 85 % of soil samples; its degradation product (2-chloro-4-(methylosulfonyl) benzoic acid (CMBA)) was present in 43 % of soil samples. In 17 % of sediment samples, CMBA was detected. Triketones were detected occasionally in surface water samples. The chemometric analysis (clustering analysis (CA), single-factor analysis of variance (ANOVA), N-Way ANOVA) was applied to find relations between selected soil and sediment parameters and herbicides concentration. In neither of the studied cases a statistically significant relationship between the concentrations of examined herbicides, their degradation products and soil parameters (organic carbon (OC), pH) was observed.


Assuntos
Sedimentos Geológicos/análise , Herbicidas/análise , Poluentes do Solo/análise , Poluentes Químicos da Água/análise , Atrazina/análise , Cromatografia Líquida de Alta Pressão , Cicloexanonas/análise , Mesilatos/análise , Polônia , Extração em Fase Sólida
11.
Waste Manag ; 44: 135-46, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26184898

RESUMO

This paper presents completed research on the purification of undiluted raw water and organic condensates obtained in biomass thermal conversion processes such as gasification, which are rarely addressed in published studies. However, similar studies involving the characterization and purification of aqueous solutions obtained from process gas treatment after the gasification of biomass are available. Condensation of water-organic condensate from process gas helps to reduce the amount of water required by the purification process and the cost of the process technology and water consumption. Oil scrubbers can be used in this case instead of water scrubbers. In this case, the obtained condensate must be subjected to purification processes. This paper presents the results of our research, possible methods of treatment (chemical and biological methods), and the approximate cost of the reagents required for the purification of condensate for specific assumed degrees of purification. The best results from the chemical purification using the Fenton method were obtained with the ratio V(H2O2)/V(cond.) = 6.0 and the ratio V(H2O2)/Fe = 0.0375. To prevent precipitation of ferric hydroxide, this value can be reduced 20-fold, which reduces the total degree of purification to 90%. The cost of almost complete cleaning of tested condensates was calculated to be approximately 2000 USD per/m(3). This cost can be reduced by a factor of approximately four assuming 100% cleaning for 2-furaldehyde, furfuryl alcohol and phenol; acetaldehyde, propane-2-one (acetone), methanol and acetic acid are oxidized by 50%.


Assuntos
Biomassa , Fontes Geradoras de Energia , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Incineração , Modelos Químicos
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