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1
Content available remote Niobia supported on silica as a catalyst for Biodiesel production from waste oil
100%
EN
The activity and stability of niobia supported on silica catalyst have been tested in continuous micro-pilot reactors, for biodiesel production starting from acid vegetable oils. A catalyst was prepared by the impregnation of silica pellets with a loading of 12% of Nb and was extensively characterized. The activity of this catalyst in both esterification and transesterification was tested in a continuous micro-pilot laboratory plant in which acid oil was fed (FFA 10% w/w) at a temperature of 220°C and at a pressure of 60 bar. The niobia based catalyst resulted in a very active catalyst in both esterification (FFA conversion = 95-90%) and transesterification reactions (FAME yield = 80-90%), and the activity remained quite constant for more than 100 h on stream. Notwithstanding this stability, a non-negligible leaching phenomena has been detected, in the case of long-time continuous runs, as the Nb concentration on the spent catalyst resulted lower than that on the fresh one. The obtained result confirms that the leaching of the active specie is one of the most strong problem in heterogeneous catalysis for biodiesel production.
EN
The glyceric fraction, forming as a side product in the process of production of biodiesel from plant oils, does not consist, how it results from many popular papers, of practically glycerine only but is a complex mixture of many substances, including toxic ones, and the glycerine content does not usually exceed 50%. In this paper the results of research on the influence of the kind of raw material, the quantity and kind of catalyst and the conditions of transesterification process on the quantity and composition of glyceric fraction.
PL
Frakcja glicerynowa powstająca jako produkt uboczny w procesie produkcji biopaliw z olejów roślinnych nie składa się, jak to wynika z wielu popularnych opracowań, praktycznie wyłącznie z gliceryny, lecz jest złożoną mieszaniną wielu substancji, także toksycznych, a zawartość gliceryny z reguły nie przekracza 50 %. W pracy przedstawiono wyniki badań wpływu rodzaju surowca, ilości i rodzaju katalizatora oraz warunków prowadzenia procesu transestryfikacji na ilość i skład frakcji glicerynowej.
EN
Recently, problems concerning the necessity of increasing the contribution of renewable energy are raised very often. In the aspect of combustion engines, the most common and promoted method consists in making liquid fuels from vegetable raw materials, which are subsequently added to conventional mineral fuels. In this study, the authors’ interest lies in the glycerin fraction, a side product of biodiesel production. Thus, it can be concluded that after phase separation, biofuel and glycerol are obtained and then glycerol can be utilized in the cosmetic, pharmaceutical or any other industry. However, in reality, we have to do with a three-stage equilibrium process, therefore, in the process of biodiesel production it is not glycerin that we deal with but a mixture of many substances of which glycerin is the main component. The amounts and contents of glycerin phases obtained in various technological conditions have been studied. Refined rapeseed oil, raw rapeseed oil and waste rapeseed oil were used as raw materials in biodiesel production.
EN
Biodiesel is currently preferred for consumption and has been widely used as a substitute for diesel. This study aimed to determine the effect of various methanol-to-oil ratios in the esterification process and also the effect of hydrotalcite catalyst weight on the transesterification product. The catalyst was characterized with SEM, XRD, FTIR, and TG-DTG-DTA. The esterification process was operated at various oil-to-methanol ratios, i.e., 1:12–1:36 and the transesterification was performed using several catalyst weights, 0.5%–2.5%. The results showed that the optimum conditions of esterification were at the 1:30 molar ratio of oil-to-methanol, which decreased the amount of acid number by 95.75%, while the optimum condition of transesterification was at 1.5% catalyst weight. The characteristics of biodiesel using 0.5–2% hydrotalcite catalyst (acid number, total glycerol, free glycerol, ester levels, viscosity, density, oxidation stability) have met the Indonesian biodiesel standard of SNI-04-7182-2012.
EN
In bioprocesses lipases are typically used in immobilized form, irrespective of type of reaction systems, to ensure an even distribution of catalysts in water restricted media and/or to facilitate separation and reuse. In these studies we report on the selection of appropriate enzyme-carrier preparation for hydrolysis reaction in aqueous and biphasic systems and transesterification in organic solvent. For this Candida rugosa lipase was bound by adsorption or covalent attachment onto various carriers to give 24 preparations. Selection of proper preparation was based on reactivity, thermal stability (4 h at 60°C), possibility of drying and operational stability in 17-23 successive batch processes of 4-nitrophenyl palmitate hydrolysis in water. Activity of preparations varied from 20 to 5100 U∙mL-1 but the most stable preparations were those of moderate activity: bound by adsorption or covalent attachment to NH2-Kieselgel or acrylic carrier (retained activity over 90%). Selected preparations were used for hydrolysis of ethyl (1-butyryloxyethyl)-phenylphosphinate in biphasic system, and, after drying, in ethyl (1-hydroxyethyl)-phenyl-phosphinate transesterification. In this study operational stability was the principal criterion of selection. In water system, lipase covalently bound to NH2-Kieselgel was the best - preserved 50% of initial activity in consecutive batch processes. In biphasic system and lipase covalently bound to acrylic and NH2-Kieselgel the values were 90 or 77%, respectively, whereas in organic solvent, when lipase was immobilized on NH2-Kieselgel by adsorption, it was 50%. Thus, NH2-Kieselgel appears to be an universal matrix for investigated lipase immobilization and can be used in all reaction systems.
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.
7
Content available remote Biorefineries - from biofuels to the chemicalization of agricultural products
88%
EN
The recent research into the viable economy in sustainable energy from renewable sources has prompted a review into the potentials of Polish-oriented raw material sources as a catalyst for technological advance, product diversification and consumer satisfaction. The elongation of the process chain in vegetable (rape seed, potato), alcohol additives and glycerin processing has been found to drastically improve energy balances for the short processing methods adopted presently and can make Poland self sustainable in the future.
EN
A carbon-based solid acid catalyst was prepared by the sulfonation of carbonized seed shells of Jatropha curcas (J. curcas L.). The structure of amorphous carbon consisting of polycyclic aromatic carbon sheets attached a high density of acidic SO3H groups (2.0 mmol · g−1) was identified with scanning electron microscopy (SEM), fourier transform infrared (FTIR) spectroscopy, powder X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The performance of the solid acid catalyst was evaluated for biodiesel production in the esterification of oleic acid with methanol. 95.7% yield of biodiesel was obtained after 2 h reaction and the conversions with reused catalyst varied in the range of 95.7% to 95.1%, showing better activity and stability than commercial catalyst amberlyst-46. It was also observed that the prepared catalyst showed enhanced activity in the transesterification of triolein with methanol when compared with other solid acid catalysts. A synergistic effect results from the high density of SO3H groups and the good access of reactants to the acidic sites can be used to explain the excellent catalytic activity, as well as the strong affinity between the hydrophilic reactants and the neutral OH groups bonded to the polycyclic aromatic carbon rings.
EN
Increased interest in development of alternative fuels used to power combustion engines is caused by excessive use of fuels obtained from mineral sources. Depletion of resources, political aspects as well as the negative impact on the environment are commonly discussed issues in relation to fossil fuels. On the other hand, biodegradability, lower toxic components emissions and interchangeability with mineral fuels are commonly described benefits related to biodiesel, interpreted as fatty acid methyl esters obtained from fatty raw material. Also the multiplicity of raw materials that can be used for production promotes popularization of the biodiesel. However the variety of raw materials can have significant impact on the number of physicochemical properties of alternative fuels due to the differences in molecular structures forming given type of raw material. The article presents analysis of properties of different types of biodiesel and its mixtures with diesel according to the outlines presented in the quality standards for mineral and alternative fuels. Alternative fuels were produced in the laboratory setup from swine, poultry, rape and sunflower fatty raw material. Such parameters as: density, kinematic viscosity, flash point, acid value, oxidation stability, cold filter plugging point, sulphur content, water content and total contamination were examined, based on the results, the quality of the biofuels was evaluated. Study confirms that biofuels derived from plant origin fatty raw material present favorable results in the aspect water content, total contamination, acid value and cold flow properties, thus biofuels derived from animal origin raw fatty material presents lower density and sulphur content.
PL
Olej słonecznikowy poddano reakcji transestryfikacji z udziałem metanolu oraz biokatalizatora enzymatycznego (Lipaza B z Candida antarctica immobilizowana na Immobead 150) lub homogenicznego katalizatora zasadowego (KOH). W reakcji transestryfikacji stosunek molowy metanolu do oleju wynosił odpowiednio 4:1 i 6:1. Proces prowadzono w układzie tradycyjnego ogrzewania oraz w układzie reaktora przepływowego z ogrzewaniem mikrofalowym. Ogrzewanie energią mikrofalową znacząco skraca czas reakcji przy jednoczesnym wzroście jej wydajności.
EN
Sunflower oil was transesterified with MeOH to biodiesel on homogenous KOH catalyst or on an enzymatic catalyst (lipase B from Candida antarctica immobilized on Immobead 150) in microwave and conventionally heated reactors. The microwave irradiation resulted in an acceleration of the reaction and increasing the product yield.
EN
While high production of palm oil improves the community economy, it has the potential to damage the environment because it produces the waste containing quite a lot of residual oil. The wastewater generated by this production process flows into the cooling pond before it is further processed in aerobic and anaerobic ponds. The residual oil contained in the cooling pond can be collected and used, e.g. as raw material for biodiesel production. This research aimed to produce biodiesel by utilizing the oil extracted from cooling pond wastewater through the esterification method with a sulfonated carbon catalyst and a transesterification method with the Na2CO3 catalyst. The sulfonated carbon catalyst was made from the palm kernel shells as a solid waste of the palm oil plant. In order to study the optimum amount of catalyst usage, the catalyst ratio was varied, i.e. 8–16% for the esterification process and 1–3% for the transesterification process. The reuse performance of sulfonated carbon catalysts was varied three times. On the basis of the research results, sulfonated carbon catalysts were proven to be effective as heterogeneous catalysts in the esterification process because they can reduce acid level to below 5 mg KOH/g oil. The sulfonated carbon catalyst ratio of 12% was the optimum ratio which can reduce the acid level to 4.62 mg KOH/g oil. The reuse of sulfonated carbon can reduce the acid level to 6.9 mg KOH/g oil at the first reuse. In the transesterification process, the optimum ratio of the Na2CO3 catalyst of 3% was found. The biodiesel produced has met the biodiesel characteristics of National Indonesian Standard (SNI of 7182:2015) with the saponification number of 197.18 mg KOH/g oil, free glycerol of 0.09%, FAME content of 96.79%, and density of 886 kg/m3.
EN
The studies showed that alkaline lipase from Pseudomonas fluorescens enables an irreversible transesterification of vinyl esters to give enantiomeric excess (eeR) of about 80% using vinyl butyrate as acyl donor and diisopropyl ether as a solvent, at partially optimized conditions. For the native lipase the process was adequately described by a five-parameter Ping-Pong Bi Bi model for both enantiomers plus expression accounting for the formation of enzyme-acyl donor complex, but for the same lipase supported on mesoporous materials of SBA-15-Oc type, R-product inhibition also had to be taken into account. The use of hydrophobic support increased by more than two-fold the rate of the S-solketal conversion but even more that of R-solketal. Thus the immobilization of lipase had very positive effect on the process kinetics but decreased its enantioselectivity.
EN
The conventional process for biodiesel production by transesterification is still expensive due to a need of high excess of alcohol required and its recovery by distillation. The use of a reactive distillation process can reduce the amount of alcohol in the feed stream as it works on a simultaneous reaction and separation. In the present study, a mathematical model has been developed for biodiesel production from triglycerides in a reactive distillation column, which has been validated with the reported data and CHEMCAD results. The effects of process parameters such as methanol to oil feed ratio, feed temperature, and reaction time have been investigated. The sensitivity analysis shows that yield of ester increases with methanol to oil ratio and number of stages, however, it decreases with fl ow rate. The MATLAB simulated results show that methanol to oil molar ratio of 5:1 produces 90% (by wt.) of methyl ester in a residence time of 4.7 minutes.
PL
Celem badań była ocena doraźnego wpływu surowej, nieoczyszczonej fazy glicerynowej, powstałej w wyniku transestryfikacji oleju posmażalniczego, na wegetację roślin. Badania podstawowe wykonano na poletkach doświadczalnych, założonych na trwałych użytkach zielonych oraz w donicach z kukurydzą. Na sześciu poletkach o powierzchni 1,5 m2 każde rozprowadzono równomiernie wodny roztwór fazy glicerynowej, dwukrotnie w ilości: 3, 33, 66, 100 kg fazy glicerynowej przeliczonej na ha oraz trzeci raz w ilości: 200, 500, 750, 1000 kg*ha-1. Do donic, wypełnionych 16 kg ziemi, wprowadzono jednorazowo fazę glicerynową w ilości: 0,5, 2,5, 5,0 g, również w postaci wodnego roztworu. Określano przyrost względny masy zielonej w stosunku do masy zebranej na poletkach kontrolnych. Nie zaobserwowano istotnego wpływu fazy glicerynowej na zmianę masy zielonej, zbieranej na terenie trwałych użytków zielonych, natomiast zaobserwowano hamujące oddziaływanie na przyrost kukurydzy uprawianej w donicach. W wyniku analizy chemicznej fazy glicerynowej wykazano 17-procentowy udział metanolu. Ze względu na ryzyko skażenia środowiska stwierdzono, że konieczne jest usuniecie tego związku przed wprowadzeniem większej ilości fazy glicerynowej do gleby.
EN
The study aimed at evaluating the influence of raw, unrefined glycerol phase, resulted from transesterification process of waste cooking oil, on plant vegetation. Basic investigations were conducted on experimental plots, established on the permanent grassland and in the pots with maize plants. On six plots of 1.5 m2 area each, the aquaeous solution of glycerol phase was uniformly distributed three times: twice at the rates of 3, 33, 66, 100 kg glycerol phase per 1 ha, and the third time - at the rates of 200, 500, 750, 1000 kg*ha-1. To the pots, filled up with 16 kg soil, the glycerin phase was added once in doses 0.5 g, 2.5 g and 5.0 g, also in aqueous solution. The gain of green matter was determined in relation to green matter of crop harvested from the control plots. No significant effects of the glycerin phase on relative changes in green matter yield harvested from the terrain of permanent grassland, were found. However, an inhibitory impact on the growth of maize plants in pots was observed. The chemical analysis of glycerin phase showed 17% methanol content in it. Due to the risk of environment contamination it is necessary to remove methanol before introducing more glycerol phase into soil.
EN
In this present study, biodiesel was synthesized as per ASTM method by using algae as a raw material, which in the environment is considered as being a harmful waste and of a nature that blooms in ponds, lakes and reservoirs. In order to improve fuel quality, the transesterification process was carried out in this study so as to remove fatty acids and thereafter, analyze several fuel parameters of the biodiesel were determined. The calorific value of the biodiesel and its specific gravity was 42660 kJ/kg and 0.803 g/cm3 respectively. The viscosity of the sample was found to be 1.99. The cetane number of diesel fuel ranged from 40 to 55 and for the biodiesel it was found to be 47. The flashpoint and firepoint of the sample was recorded as 80°C and 94°C respectively. The conclusion is that it is worthy to mention that this process does not require high-end technology; hence, it could be used in the energy generation process in remote areas and as an alternative resource, as well.
EN
Two polyesters, i.e. an aromatic one: poly(butylene terephthalate) – PBT and an aliphatic one: poly(ĺ- -caprolactone) – PCL were mixed in melt to obtain a biodegradable product. DSC, 1H NMR, SEM, WAXS, SAXS, BOD and PALS measurements were performed to study the homopolymers as well as their physical blend and copolyesters. The latter were obtained due to the transesterification reaction. Ortho-positronium (o-Ps) annihilation lifetimes were used to create the distributions of free volume. The progressive changes in probability density function of free volume, i.e. increase in large free volume holes contribution to the total free volume, appearing when going from the homopolymers to the blend and then to the copolyesters reflect the influence of: the addition of aliphatic polyester, the weight fraction of it in the composition and transesterification. The higher contribution of larger free volume holes corresponds well with the reduced crystallinity of compositions revealed in X-ray diffraction and the worsening of the regularity of structure of the macromolecules involved in formation of crystals, deduced from the 1H NMR.
EN
The olive mill wastewater, effluents from the trituration of olives, are treated in most Mediterranean countries by natural evaporation. However, this method of treatment is a source of air and soil pollution by the generation of solid waste, called olive mill waste cake. This work focused on extracting of vegetable oil from this by-product for biodiesel production by transesterification. The extraction took place with a Soxhlet extractor, using hexane as solvent. The vegetable oil and biodiesel were characterized by measuring the physicochemical parameters that identify them according to AFNOR standards. The extraction results show that the oil yield is 21.28%. The oil obtained is characterized by density, water and ash content, acidity, saponification, peroxide and ester. The yield of the oil esterification reaction is 86.41% or about 185 Kg of biodiesel/ton of olive mill waste cake, and in terms of energy 2783.7 MJ or 2 GW.t-1. The biodiesel produced is comparable to petroleum diesel according to EN 14214, 2013.
PL
Scharakteryzowano olej rzepakowy jako surowiec do produkcji biodiesla i opisano etapy procesu transestryfikacji. Oceniono metody wydobywania oleju rzepakowego poprzez tłoczenie w warunkach gospodarstwa rolnego i scharakteryzowano oleje pod względem przydatności do reakcji metanolizy (zawartość fosforu, LK, LOO, skład kwasów tłuszczowych). Przeprowadzono wstępne laboratoryjne reakcje transestryfikacji i na ich podstawie wytypowano parametry reakcji w skali ćwierćtechnicznej. Stopień konwersji oleju do estrów metylowych kwasów tłuszczowych (EMKT) oznaczano poprzez pomiar współczynnika załamania światła.
EN
Rapeseed oil has been characterized as a raw material in biodiesel production and stages of this process have been described. An evaluation of methods of extracting oil from rapeseed has been performed. The oil has been evaluated on its usefulness for methanolysis process (phosphorus content, fatty acid composition, acid and peroxide values). Preliminary transesterification reactions have been conducted on a laboratory scale and, based on the obtained results, parameters for household scale process have been chosen. The stage of oil-into-FAME conversion has been determined through refractive index measurement.
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