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EN
The aim of the study was to determine the sulphur content in 33 samples of oils pressed from different species of vegetable. The unconventional oil samples were purchased from commercial store. Oils was analysed in terms of sulphur content according to the method using X-ray fluorescence spectrometry with wave dispersion, that is described in the PN-EN ISO 20884, 2012 standard. Obtained results of sulphur analysis were presented as the arithmetic mean ± standard deviation (from three replicates) and statistically analysed using the Statistica 13.0 PL program. In order to indicate significance of differences between oils analysis of variance (ANOVA) with Tukey’s test of p ≤ 0.05 significance level was used. The statistical analysis indicated significant differences in the content of sulphur content in the analysed vegetable oils, which could affect the lubricity of prepared fuel blends and in some cases significantly, increase the sulphur content above acceptable value 10 ppm. It was concluded that vegetable oils could be a suitable raw material improving the lubricating properties of low-sulphur diesel oils. However, due to significant differences in the sulphur content in the analysed samples, the content of this element should be analysed beforehand in order to eliminate the possibility of exceeding the permissible level of sulphur in transport fuels.
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.
EN
The aim of the study was to determine the possibility of using the unconventional vegetable oils for the biofuel production. The research material were cold-pressed oils from the seeds of milk thistle, hemp and evening primrose. After conducting the initial physicochemical characteristics of oil samples, including the determination of sulphur content, acid number, viscosity at 40°C, density at 15ºC, oxidation stability and fatty acid composition, analysed oils have been subjected to the transesterification process. The roduced methyl esters were further characterized by the above-mentioned features. Additionally, the temperatures of cold filter plugging point, cloud point and flash point were determined. On the basis of the conducted analyses it was demonstrated that the obtained oils, due to the high, far in excess of acceptable, values of the viscosity and density, and too low oxidative stability could not be used as a pure fuel. A similar conclusion was formulated in case of the produced methyl esters.
EN
The aim of the study was to evaluate the physico-chemical parameters of the fuel blends consist of a diesel oil and waste products, such as a pyrolytic oil from car tires and a frying oil. The samples were characterized by the kinematic viscosity at 40°C, density at 15°C, acid value, sulphur content, temperature of flash point and temperature of cold filter plugging point. The obtained results indicated that the fraction of the pyrolysis oil due to the very low temperature of flash-point and high sulphur content is a difficult material to use in the biofuels sector. While the sulphur content of that material may be reduced by the desulphurisation, whereas the increasing temperature of flash point, which greatly influenced the low value of this parameter for the mixture, is problematic. What is more, a high degree of oxidation of the frying oil determined too low stability of the produced methyl esters, and thus the fuel blends.
EN
The aim of the study was to show the validity of determining the quality of oils intendent for the biofuels production. One of the main discriminant that should be used to assess the suitability of oil raw materials for the fuel purposes is the composition of fatty acids. The research was conducted on 13 different samples of vegetable oils, that were cold-pressed from the seeds of various species, including rape, camelina, flax (light and dark), mustard, milk thistle, hemp, evening primrose oil, amaranth, sunflower, soybean, and cumin. The analysis of the fatty acid composition showed significant differences between the analysed oil samples, both within the species and varieties of oilseeds. The results indicate the need for continuous quality control of oils and fats led to the production of biodiesel in the small households and large commercial enterprises, because as it was indicated by the analysis of fatty acids composition rape seeds of different varieties are characterized by the diverse quality.
6
Content available Waste tires as a source of valuable chemicals
EN
The aim of the study was to determine the possibility of the isolation of valuable chemical compounds from pyrolysis oil obtained from the pyrolyzed waste car tires. Produced pyrolysis oil were subjected to a distillation process to isolate medium naphtha fraction average naphtha that contains limonene, which according to the literature data, can be used as an environmental friendly solvent in a number of cleaning agents. Considering the boiling point of limonene (176°C), the medium fraction of the separated oil was re-distilled to isolate compounds with temperature of boiling point between 174-177°C. The prepared sample was analysed by gas chromatography coupled with mass spectroscopy. Based on the chromatographic analysis, it was found that in a separate sample of pyrolysis oil the highest share constituted toluene, and then cyclobutane, benzene derivatives, which is essential in the chemical industry. The share of limonene was low (approx. 1%), what is explained by too high temperature of the pyrolytic process. The results of analysis and literature allow unequivocally state that in order to separate specific compounds from pyrolytic oil, parameters of this process should be first determined in pilot studies. In conclusion, it is believed that the pyrolysis of tires is suitable method of disposing of the waste, thereby obtaining products containing valuable compounds for the fuel and chemical industries.
EN
The aim of the study was to determine the ultrasounds treatment of frying oil on their properties important in order to biodiesel production. The research material was a frying oil, which prior to transesterification oil was treated with ultrasounds (37 kHz) during 15, 30 and 60 min. In next step, prepared samples were analysed in terms of fatty acid composition, acid value, FFA % and then subjected to alkali transesterification process. After producing methyl esters the yield of biodiesel was analysed with thin liquid chromatography technique (TLC), and then samples were characterized in terms of viscosity in 40 °C, density at 15 °C, acid value, sulphur content and flash point. The results showed that an ultrasonic treatment had a little impact on the fatty acid composition of the test samples. The yield of biodiesel was the higher the longer time of ultrasounds treatment were used. One the other hand, determined with thin liquid chromatography technique yield of biodiesel was the higher the longer time of ultrasounds treatment were used. What is more, the ultrasounds treatment of oil before transesterification process had no impact on viscosity, density and acid value of these samples, while flash point values and sulphur content were changed.
EN
The aim of the work was to determine the effect of oils quality and transesterification method on the degree of conversion of the fatty acids. Material consisted of 4 samples of oil: rapeseed oil obtained by the laboratory hot pressing of rape seeds oils in approx. 80 °C, waste rapeseed and palm oils and one refined rapeseed oil. Oils used in the one-stage transesterification were characterized by a lower hydrolysis and oxidation degree than the oils used in two-stage transesterification (double-base and base-acid method). The quality of the obtained crude methyl esters was determined in terms of acid number, peroxide value, the lipid composition by thin layer chromatography. Quantitative testing of the degree of transesterification and the share of individual esters of fatty acids was conducted by gas chromatography. Studies have shown that that degree of conversion of the fatty acid methyl esters is dependent on both the quality of the oil and the method of transesterification. If oils are characterized by a good quality, then a method of transesterification is less important. However, if oils are heavily contaminated, then the right technology for their transesterification should be chosen, e.g. oil with high content of FFA should be subjected to base-acid transesterification. Studies have shown. If oils are characterized by a good quality, then a method of transesterification is less important. However, if oils are heavily contaminated, then the right technology for their transesterification should be chosen, e.g. oil with high content of FFA should be subjected to base-acid transesterification.
EN
Almost all kinds of fuel applied in combustion engines come from refining industry, in which crude oil serves as basic raw material. However, there are also searched other sources of hydrocarbons which can be used directly or as additives to conventional fuels. The most popular in this regard are vegetable oils such as rapeseed oil, from which are produced esters used as fuel for diesel engines. On the other hand, as additives to gasoline can be used alcohols derived from the fermentation of agricultural products. Another way to obtain liquid hydrocarbons is pyrolysis of scrap tires. In this article, such pyrolytic product is analysed in terms of its fluorescence properties compared to the fluorescent properties of substances derived from the distillation of the pyrolysis product in three following temperatures: 160, 204 and 350 ºC. All the tested substances show relatively strong fluorescence in ultraviolet range. Fluorometric spectra were performed applying the spectrofluorometer Hitachi F-7000 FL with 1x1 cm quartz cuvette. Studied substances were previously diluted in n-hexane to obtain concentration 4 ppm. Amount of fluorescent peaks and their positions depends on kind of distillate. Ipso facto fluorescence method seems be suitable much more – than chemical analyse – for quick identification of substances constituting a components of distillate obtained from pyrolytic product.
EN
The aim of the study was to determine the possibility of using small seeds of rape (diameter <1.6 mm,) perceived as a raw material of inferior nutritional quality, for the biofuels production. Research material was samples of industrial mass of rapeseeds originating from three Polish regions. The seed mass was cleaned in a sieve separator, removing mineral matter (stones), cereal grains, stems and dusts. Then, the sample was sifted through a set of sieves and two fractions were received: seeds with diameter >1.6 mm – sample F1 and with diameter < 1.6 mm – sample F2. Each fraction was characterized by its share in bulk mass, moisture content, 1000 seeds weight, yield of pressing, fat content and phosphorus content. Cold-pressed oils were determined in terms of total and unhydrated phosphorus content, acid value and fatty acids content. Fractionation by weight rapeseeds with using an industrial sieve separation may provide a simple method for improving the technological value of the raw material used for food purposes, and thus obtain fine seed that could be intended exclusively for the production of technical oil. Despite the stated inferior quality of small seeds, it was found that the increased values of some discriminants would not have impact on the technology of biofuel production and cost of production.
PL
Celem badań było określenie wpływu alkoholu etylowego i metylowego na jakość otrzymanych paliw alternatywnych. Materiał badań stanowiła próbka handlowego oleju rzepakowego, która posłużyła do przeprowadzenia procesu etanolizy i metanolizy. Otrzymane rzepakowe estry etylowe (REE) i metylowe (RME) przeanalizowano pod względem: zawartości wody, stopnia hydrolizy (liczba kwasowa i %WKT – (Wolnych Kwasów Tłuszczowych)), stabilności oksydacyjnej (test Rancimat) gęstości w temp. 15°C, lepkości w temp. 40°C, zawartości siarki oraz temperatury zapłonu. Następnie sporządzono mieszaniny RME i REE z ON w proporcjach 1:3, 1:1 i 3:1, dla których przeprowadzono ww. oznaczenia fizyko-chemiczne. Wykazano, że rodzaj użytego alkoholu (metylowy, etylowy) w niewielkim stopniu różnicował jakość otrzymanych estrów rzepakowych. Wartości większości badanych wskaźników jakościowych czystych RME i REE były zgodne z dopuszczalnymi w normie wartościami. Wyjątek wykazano natomiast w przypadku wartości liczby kasowej i %WKT, które przekraczały graniczną wartość 0.50 mg KOH/g oleju i 0.25 %WKT, oraz stabilności oksydacyjnej (>6,0 h). Podobną zależność wykazano także w przypadku mieszanin ON z REM i REE. Jakość otrzymanych mieszanin etylowych i metylowych estrów rzepakowych i ON była warunkowana wielkością udziału poszczególnych składników. Na podstawie przeprowadzonych badań stwierdzono, że sporządzone mieszaniny estrów rzepakowych i ON spełniały większość wymagań stawianych w normie PN-EN 14214, w związku z czym przypuszcza się, iż stanowiłyby one odpowiednie alternatywne paliwo do silników o ZS.
EN
The aim of the study was to determine the effect of ethyl and methyl alcohol on the quality of the alternative fuels. The research material was a sample of commercial rapeseed oil, which was used to carry out the ethanolysis and methanolysis processes. Received rapeseed ethyl (REE) and methyl (RME) esters were analyzed in terms of: the water content, the degree of hydrolysis (acid number and % FFA (Free Fatty Acid)), oxidative stability (Rancimat test), density at temp. of 15 ºC, viscosity at temp. of 40 ºC, sulfur content as well as the fuel flash point. A mixtures of REE and RME with ON were produced in the ratio 1:3, 1:1 and 3:1. Those samples were analyzed in terms of above physico-chemical determination. It has been shown that the kind of alcohol (methyl, ethyl) slightly differentiate the quality of the obtained esters of rapeseed oil. The values of most of the quality parameters of studied pure REE and RME were consistent with PN-EN 14214 standard. An exception has been shown in the case of the acid value and %FFA, which exceeded the limit value of 0.5 mg KOH/g and 0.25 %FFA, and oxidative stability (> 6.0 h). A similar relationship was also demonstrated in the case of mixtures of the REE, RME and ON. Quality of obtained fuel mixtures were determined by share of individual components. During the tests it has been shown that RME and ON mixtures meet requirements according to PN-EN 14214 standard, therefore are suitable as CI engines.
PL
Celem pracy było porównanie parametrów fizyko-chemicznych oleju napędowego, oleju pirolitycznego ze zużytych opon samochodowych oraz 3 pirolitycznych frakcji nafty. Próbki scharakteryzowano pod względem lepkości kinematycznej w temp. 40°C, gęstości w temp. 15°C, liczby kwasowej, zawartości siarki, temperatury zapłonu oraz stabilności oksydacyjnej w temp. 110°C. Na podstawie przeprowadzonych badań wywnioskowano, że olej pirolityczny oraz średnia i ciężka frakcja nafty mogłyby posłużyć jako komponenty mieszanek paliwowych, jednakże uprzednio powinny one zostać poddane procesom rafinacji.
EN
The aim of the study was to compare the physico-chemical parameters of diesel fuel, pyrolysis oil from used vehicle tires and 3 fractions of pyrolysis naphtha. The samples were characterized in terms of kinematic viscosity at 40°C, density at 15°C, acid number, sulfur content, ignition temperature and oxidation stability at 110°C. Based on the study it concluded that pyrolysis oil, and medium and heavy fraction of oil can be used as components in fuel blends.
PL
Celem pracy była ocena parametrów fizyko-chemicznych 10 próbek olejów napędowych zakupionych na olsztyńskich stacjach paliw. Próbki scharakteryzowano pod względem zawartości wody, lepkości kinematycznej w temp. 40°C, gęstości w temp. 15°C, liczby kwasowej, zawartości siarki, temperatury zapłonu i zablokowania zimnego filtra, stabilności oksydacyjnej w temp. 110°C oraz zawartości zanieczyszczeń stałych. Na podstawie przeprowadzonych analiz wykazano, że zakupione paliwa nie spełniły wymogu stabilności oksydacyjnej, której dopuszczalna wartość jest określona na poziomie powyżej 20 h. Pozostałe badane wyróżniki jakościowe były zgodne z wymaganiami norm.
EN
The aim of the study was to evaluate physico-chemical parameters of 10 samples of diesel fuel purchased from Olsztyn stations. The samples were characterized for water content, kinematic viscosity at 40°C, density at 15°C, acid number, sulfur content, flash point and cold filter plugging point, oxidative stability at 110°C and solids content. Based on the analyzes it was shown that the fuel purchased did not meet the requirement oxidation stability, which limit value is set at a level above 20 hours. Other tested discriminants of quality were consistent with the requirements of the standards.
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