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1

Spectrofluorimetry of chosen distillates of oil after pyrolysis of scrap tires

Otremba Z., Ambrosewicz-Walacik M.

Journal of KONES

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2018

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Vol. 25, No. 2

262--268

EN

One of way to obtain liquid hydrocarbons can be pyrolysis of scrap tires. The hydrocarbon substances produced by this method may be an addition to traditional fuels, i.e. gasolines or fuels for diesel engines. In laboratory conditions at Department of Mechatronics of University of Warmia and Mazury there were obtained pyrolytic products and prepared three distillates related to temperatures 160, 204 and 350ºC. Analyses of shapes of fluorescence spectra were carried out in Department of Physics of Gdynia Maritime University. Spectra of fluorescence were prepared applying the spectrofluorimeter Hitachi F-7000 FL, which allows applying of excitation wavelength from 200 nm until 600 nm, whereas analysing of emitted, can be performed until 750 nm. In here reported study excitation and emission range for the most intense fluorescence are presented. There were prepared four solutions of pyrolytic products in the n-hexane: 4 ppm, 20 ppm, 100 ppm and 500 ppm. In order to show dependence of intensity fluorescence and shapes of excitation-emission spectra on type of distillate and concentration both kind of visualization – three-dimensional and as contour maps – are shown in this article. In analysed range of wavelengths, intensity of fluorescence grows with concentration of oil, whereas structure of the shape of spectra simplify when concentration increases. The presented effects associated with the fluorescence of pyrolysis products allow to predict the possibility of developing a method for determining the content of these substances in mixtures with petroleum refining products and other liquid hydrocarbons.

2

Properties of the Baltic crude oil in the oil-in-water emulsion form : excitation-emission spectra

Baszanowska E., Otremba Z.

Journal of KONES

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2018

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Vol. 25, No. 1

7--14

EN

Due to the fact that marine environment contamination by oil substances are not uncommon, it is necessary to improve the ability of determine their origin. Therefore, research on the possibility of recognizing the type of oil using its individual characteristic manifested in the processes of fluorescence excitation has been undertaken. Oil pollutants present in seawater mainly coming from ship drives, tankers, pipelines or sea bottom seeps, moreover oil leaks from offshore extraction equipment also are possible. For this reason, the crude oil extracted from the Baltic Sea deposit in the Polish Maritime Areas has been chosen for tests. Fluorescence properties of water containing small amounts of oil (concentrations from 5.59 to 55.4 ppm) in the form of oil-in-water emulsion were tested. Individual samples were assigned matrices of fluorescent values for different wavelengths, while excited by monochromatic light also for different wavelengths. The obtained matrices were visualized as a contour maps and 3D charts. For considered concentrations of crude oil dispersed in water, the wavelength-independent fluorescence maximum was determined. Obtained result indicates that in the studied wavelength range, the total fluorescence intensity is proportional to the oil concentration only for the lowest oil concentrations. The analysis of the objective parameter of the difference between the shapes of spectra indicates the similarity of the spectral shape for the lowest oil concentrations. These results are the methodological suggestion, that for the purpose of identifying the type of oil dispersed in water, spectra should be determined for sequences of different dilutions, until the excitation-emission spectra shapes become independent from the oil concentration.

3

Engine fuel characterisation based on excitation-emission spectra

Baszanowska E., Otremba Z.

Journal of KONES

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2017

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Vol. 24, No. 2

25--30

EN

Considering that correctly functioning of diesel ship engine depends on the composition of applied fuel, it is necessary to easy characterise fuels in terms of quality. Therefore taking into account above mentioned, appropriate analyses have been undertaken and the intention of this article is to inform that characterisation of fuel used in marine transport can be described by the specific parameter based on fluorescence excitation-emission spectroscopy. Therefore, for this study fuel typically used in ship engine – Diesel fuel – is considered. For analysis, Diesel fuel dissolved in n-hexane was used and several oil samples for various oil concentration were prepared. Spectrofluorometer Aqualog Horiba was used to record the excitation-emission spectra (EEMs). EEM spectra determined for each of oil concentration were described by two specific peaks for this kind of oil. Based on registered EEMs, the specific indicator - the wavelength-independent fluorescence maximum – coded in two specific wavelengths – excitation and emission, respectively, described as Exmax/Emmax was determined for considered oil concentration. Obtained results indicate the independence from oil concentration only for one detected peak described by Exmax/Emmax = 240/332. Taking into account obtained results, we can conclude that the wavelength-independent fluorescence maximum detected for excitation wavelength at 240 nm corresponds to the emission wavelength at 332 nm due to the independence from the oil concentration, could be a good indicator to characterise this kind of oil – Diesel fuel. We can conclude that the changes in the composition of fuel could be detected in EEM spectra by the change of detected peaks position.

4

Comparison of fluorometric signatures of oil residues in both marine environment and in organic diluent

Otremba Z., Baszanowska E.

Journal of KONES

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2015

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Vol. 22, No. 3

175--179

EN

The significant part of petroleum substances is transferred to the marine environment after technical activities (inevitable exploitive spills, illegal discharges). However a certain part of petroleum in seawater coming from the natural sources. Therefore, to develop the safety of natural marine environment it is necessary to track not only the anthropogenic pollutants but also the natural sources of petroleum. To distinguish both source of oil the fluorescence properties of oil can be used as the tools to oil identification. The aim of the study is to describe the optical properties of crude oil after it contact with aquatic environment based on fluorescence spectroscopy. For the study, crude oil ‘Petrobaltic’ type potentially found in marine environment due to coming from natural source was applied. To dissolve oil, two different solvent – hexane and Baltic seawater form the Gdynia coast were used. To measure the excitation-emission spectra (EEMs) of oil spectrofluorometer Hitachi F-7000 FL was applied. In the paper, we discuss the changes of oil EEMs in two cases for oil dissolved in n-hexane and for oil dissolved in seawater for various oil concentration. Obtained EEMs for oil dissolved in seawater indicate that EEMs spectrum contain the main peak – describing by the wavelength – independent fluorescence maximum, which was detected for oil dissolved in n-hexane (typical for this kind of oil). However, the intensity of oil fluorescence decreases after oil contact with seawater. This approach could allow expanding the description of complex mixtures of oils as a possible tool proposed for identification the type and origin of oil found in marine environment.

5

Fluorescence spectra of oil after it contacts with aquatic environment

Baszanowska E., Otremba Z., Toczek H., Rohde P.

Journal of KONES

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2013

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Vol. 20, No. 3

29--34

EN

The main task for natural marine environment protection is to prevent the inflow of various contaminants including oil substances and the real challenge is the ability to rapidly detect these pollutants. Moreover important is to find the source or the maker of the oil spill. In this paper, we consider fundamental physical aspects in the area of possibility of monitoring the natural marine ecosystem based on fluorescence spectroscopy. We utilize the fluorescence ability of numerous oil components – mainly polycyclic hydrocarbons. The paper concerns the spectrofluorimetric characterization of oils have been in use during exploitation of the marine fleet, i.e. lubricate oil, fuels, transformer and hydraulic oils as well as crude oils or their residues. Every kind of oil has a chance to enter the marine environment, especially in a case of ship emergency or after collision with other vessel ore shoreline structure as well as when ship enters the stranding. After discharge of oil, some of oil components are dissolved in the water, bacteria or photochemical reactions, which results in transformation of composition of oil, degrade some. Fluorescence spectrometer Perkin Elmer LS55 was applied to obtain the fluorescence spectra using different excitation wavelength in the range from 240 nm to 500 nm. We discuss the changes of the shapes of excitationemission spectra (EEMs) of various types of oil and the EEMs spectra after contact of oil with seawater as an oil-inwater emulsion, which is the most frequent form of oil in the water column. Significant changes in the shape of spectra and displacement of the peaks are observed.