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Copyright of Chemical Industry / Hemijska Industrija is the property of Association of Chemical Engineers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chemical Industry / Hemijska Industrija is the property of Association of Chemical Engineers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Jedan od mogućih pravaca dekarbonizacije i elektrifikacije teretnog i putničkog transporta je upotreba gorivnih ćelija sa vodonikom kao pogonskim gorivom. S obzirom da je primena biomase za proizvodnju električne energije u velikoj meri nekonkurentna u odnosu na vetroelektrane i solarne elektrane, njena primena za dobijanje vodonika predstavlja jedan od mogućih pravaca razvoja ovog obnovljivog izvora energije. U ovom radu su analizirane tehnologije za proizvodnju vodonika iz biodizela. Izvršena je analiza strukture i ukupnih troškova proizvodnje vodonika iz biodizela, kao i energetski bilans ovog procesa. Sagledani su uslovi korišćenja vodonika za pogon gorivnih ćelija u električnim vozilima. Sprovedena je analiza efikasnosti energetskog ciklusa: biodizel – vodonik – električna energija – mehanička energija za pogon električnih vozila. Kao krajnji rezultat izvršena je procena troškova proizvodnje kWh električne energije iz biodizela i uporedna analiza sa vozilom koje je pogonjeno dizel motorom i električnim motorom napajanim iz baterija.

Copyright of Chemical Industry / Hemijska Industrija is the property of Association of Chemical Engineers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The intensive use of grains as feed in ruminant production systems raises concerns about future food security. The replacement of food raw materials used in animal nutrition with industrial by-products and other waste biomass that are not suitable for human consumption is viewed as the most important potential strategy that can decrease foodfeed competition and increase the profitability of animal production. Crude glycerin (CG) is a byproduct of the biodiesel industry and has been used as an alternative to grains in ruminant diets in recent years. Glycerol, which is the main component of CG, rapidly participates in energy metabolism by undergoing fermentation to propionate and butyrate in the rumen. Depending on the biodiesel production method, the effect of CG, which is obtained at varying levels of purity, on ruminants may vary according to the amount of glycerol, and other impurities in it and the amount of CG added to the diet. Due to this variability, inconsistent results are obtained regarding the efficiency of CG usage in ruminants. Based on the literature, it was concluded that CG could be used in ruminant diets at levels of 10 -15% of dry matter after taking into account the levels of impurities without adversely affecting the performance. [ABSTRACT FROM AUTHOR]

Copyright of Rudarsko-Geolosko-Naftni Zbornik is the property of Faculty of Mining, Geology & Petroleum Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

U ovom je radu istražena mogućnost primjene niskotemperaturnih eutektičkih otapala za ekstrakcijsku deacidifikaciju otpadnih životinjskih masti te uklanjanje glicerola i glicerida iz sirovog biodizela. Istraživanje je uključilo odabir povoljnog katalizatora te masenog omjera katalizatora, metanola i masti koji bi rezultirali najvećom konverzijom triglicerida u metilne estere masnih kiselina. Definirano je potrebno vrijeme pročišćavanja sirovog biodizela te optimalan maseni omjer otapala i sirovog biodizela. Ekstrakcijskom deacidifikacijom pomoću niskotemperaturnog eutektičkog otapala na bazi kalijeva karbonata uspješno je reducirana kiselost sirovine uz relativno mali utrošak otapala (maseni omjer otapala i masti: 0,25 : 1,00) i kratko vrijeme trajanja procesa (30 min). Kalijev hidroksid pokazao se kao učinkovitiji katalizator. Udio katalizatora u reakcijskoj smjesi utječe više na konverziju masti od udjela metanola. Udio glicerola i glicerida reduciran je ekstrakcijom pomoću niskotemperaturnog eutektičkog otapala na bazi kolin klorida na vrijednosti manje od standardom propisane vrijednosti (EN 14214:2019). Odabrano se otapalo pokazalo selektivnim zbog toga što nije došlo do redukcije udjela metilnih estera. Pri masenom omjeru otapala i biodizela 1 : 1 i 90 min trajanja ekstrakcije postignuti su najbolji rezultati. Pročišćeni biodizel također zadovoljava standard kvalitete s obzirom na udio estera, gustoću i viskoznost.

To produce biodiesel, one of the most important factors is the quality of the oil used in the production. However, other factors such as price and availability should also be taken into consideration. Chicken wastes oil shows a very promising option for this sector, since it comes from a waste. The aim of the present study was a methodology for extraction and characterization of chicken wastes oil for production of biodiesel by ethylic transesterification, besides presenting the characterization and optimization of the process variables of the production of biodiesel, the applying of RSM involving CCD. The investigation was performed following evaluation of the characterization parameters for the oil: viscosity, density, acidity index, moisture of the sample, refractive index, and saponification index. For biodiesel, viscosity, density, acidity index and ester content were evaluated. An optimum point was reached for the production of chicken biodiesel where the concentration of the catalyst is 2.1% by mass, the oil/ethanol ratio is 1:5.5 and the reaction temperature of 30 °C; at that point, a 95% conversion was achieved. At the optimum point obtained from the statistical technique for a p-value of 0.05 the results found for the physical-chemical characterization of biodiesel are found in the ANP standards. [ABSTRACT FROM AUTHOR]

Waste glycerol from biodiesel production is a valuable raw material that has been used to produce valuable microbial metabolites. In this work, the possibility of microbial utilization of waste glycerol obtained as a by-product in biodiesel production from sunflower and rapeseed oil by the lactic acid bacterium Enterococcus faecalis MK3-10A on a laboratory level was studied. For comparison, pure glycerol and glucose were used as carbon sources. The kinetics of the microbial biomass growth, the carbon source utilization, and the lactic acid production were monitored. The bacterium E. faecalis MK3-10A better grew in the media with glucose or pure glycerol as a carbon source, but the lactic acid production rate was the highest (14.6 mg/(ml/day)) in the medium with waste glycerol from the sunflower oil-based biodiesel production. Therefore, this waste glycerol might be a promising carbon source for lactic acidbacteria cultivation and lactic acid production. [ABSTRACT FROM AUTHOR]

This study is include combustion analyzes and engine characteristics of sunflower oil methyl ester biodiesel and its diesel blends. Experimental studies were performed on a single cylinder diesel engine. Numerical operation was performed in ESE-Diesel part of AVL-FIRE software. When the results are examined, maximum engine torque for mixed fuels has obtained in 10% sunflower oil methyl ester-90% diesel (SOME10) study. Maximum cylinder pressure in all test fuels has obtained at 30% sunflower oil methyl ester-70% diesel (SOME30). With the increase in biodiesel ratio in the mixture, while NOx emissions increased, CO and HC emissions decreased. [ABSTRACT FROM AUTHOR]

Biodiesel is the first alternative fuel the physicochemical properties of which are regulated by appropriate standards: American ASTM D 6751 and European standard EN 14214. The process of biodiesel production consists of three main phases: 1) preparation of feedstock, 2) transesterification, and 3) processing of the reaction product - purification of crude biodiesel to meet the specification provided by the previously mentioned standards. The purification process of crude biodiesel is usually carried out by two notable techniques: wet and dry washing. The most commonly used process is wet washing. A major drawback in the use of water in purification process is the generation of a large amount of wastewater that greatly increases biodiesel production costs, followed by drying of the product, which requires an additional amount of energy and is time consuming. The greatest disadvantage of dry washing using different ion-exchange resins is the inability to remove glycerol and methanol from crude biodiesel to those limits prescribed by EN 14214, followed by the disposal problem of spent ion-exchange resins. Because of the aforementioned, the use of membrane technology in the process of biodiesel purification has appeared as an alternative for the existing purification techniques. The membrane filtration is environmentally friendly and requires less energy. By membrane filtration, the glycerol, methanol, and water contents in biodiesel can be decreased to the amounts prescribed by the standards. In the frame of this review article, the short overview of the possibility of using ultra- and/or micro-filtration in the purification process of biodiesel is presented. [ABSTRACT FROM AUTHOR]

Glycerol is the main byproduct of industrial biodiesel plants, and new technological routes using it as feedstock have been studied, due to the increase in world biofuel production. One of the possible applications is in the production of acrylic acid, a product with several industrial applications. This study analyzed a new process of converting crude glycerol, through purification for the removal of impurities, followed by oxidative dehydration reaction in a single step and purification until glacial acrylic acid specification standards are met. It was attested that the process is economically viable, with a payback period of 5 years for an NPV/Investment greater or equal to 2 and an IRR greater or equal to 10% per annum, or 4 years in case tax incentives offered for the development of green technologies. [ABSTRACT FROM AUTHOR]

The biodiesel inclusion in the Brazilian energy matrix still faces challenges due to the lack of diversity of raw material and the high costs associated with the stages of production, purification and phase separation of the biofuel. In this work, the potential of Catolé (Syagrus cearensis) was evaluated as an alternative source for biodiesel production, through methyl transesterification by alkaline catalysis. Given the absence of reported data on this oilseed, the aim of the present paper is to characterize the oil and biodiesel in terms of density, kinematic viscosity, and acid value. A liquid-liquid equilibrium (LLE) study of Catolé biodiesel-methanol-glycerin systems at 298.15, 308.15 and 323.15 K at atmospheric pressure was also carried out. Results showed that Catolé seed oil is a viable alternative for biodiesel production, with parameters found in accordance with the quality standards and an ester yield of 97.1%. Ternary diagrams showed that the solubility of the components lowers at low temperatures. Tie-lines evidenced higher affinity of methanol with the glycerin-rich phase. Distribution and selectivity coefficients were determined and the Othmer-Tobias and Hand correlations were applied to verify the quality of the experimental data. The determination indices (>0.97) proved the thermodynamic consistency of the data. [ABSTRACT FROM AUTHOR]

Given the fact that biodiesel produced from oil used in the food industry is not competitive with fossil-based diesel, it is necessary to use cheaper raw materials for its production. Thereby, waste edible oil, by-products of the manufacturing process of edible oils, inedible oils, and waste animal fat are considered the economically acceptable raw materials. The goal of this work was to investigate the applicability of deep eutectic solvents for extractive deacidification of waste animal fats and removal of glycerol and glycerides from crude biodiesel. Extractive deacidification of waste animal fat was conducted using deep eutectic solvent potassium carbonate - ethylene glycol (1 : 10, mol.), and it was used in mass ratio 1 : 4 (solvent : fat), at 60 °C for 30 min. Total acid number was reduced from 26.63 to 1.1 mg KOH/g fat. After purification of the feedstock, biodiesel was synthesised with different catalysts (KOH and NaOH), and KOH exhibited better conversion; therefore it was chosen for further experiments. In order to define the optimal reaction conditions, the influence of mass ratio catalyst : methanol : fat on the conversion of triglycerides into fatty acid methyl esters was investigated. At all reaction conditions, high quality biodiesel was obtained, i.e., the ester content was above the EN 14214 limit (96.5 %). The influence of catalyst load was greater than of methanol. At the highest concentration of catalyst, neutralisation of free fatty acids occurred. Biodiesel synthesised at 1 : 40 : 100 (KOH : methanol : fat) was chosen as the best, and was used for further experiments - extraction of glycerol and glycerides from crude biodiesel. For that purpose, deep eutectic solvent choline chloride - ethylene glycol (1 : 2.5, mol.) was used. The influence of mass ratio solvent : biodiesel and extraction duration was investigated. Increase in mass ratio and extraction duration resulted in a slight increase in ester content. To confirm the removal of glycerol and unreacted glycerides, samples of biodiesel before and after extraction were analysed by gas chromatography. Three samples after extraction were chosen - one at the lowest and one at the highest mass ratio of solvent to biodiesel, and one at the highest duration of extraction. Crude biodiesel contained too high concentrations of free and total glycerol. After extraction for 90 min, a significant reduction was observed - the extraction efficiencies for free glycerol, diglycerides, triglycerides, and total glycerol were: 90.77 %, 13.19 %, 10.43 %, and 21.59 %, respectively. The content of glycerol and glycerides after extraction was well below the EN 14214 limit. Density and viscosity of biodiesel were within the range defined by the European standard EN 14214. [ABSTRACT FROM AUTHOR]

Alkaline transesterification of vegetable oils or animal fats (apolar substances) with a short-chain alcohol (polar substance) is the best-known chemical route for biodiesel production. However, because they are substances of different polarities, there is a need to promote contact between the phases. Biodiesel was produced from soybean oil, methanol, potassium hydroxide, and surfactants DBB 7104 and DBB 7107. In this paper we verify whether it is better to use surfactant DBB 7104 or DBB 7107, and if there is an optimum experimental condition for the surfactant. The yield in biodiesel was verified for different production conditions on a bench scale. From a fractional experimental plan (26-2), with a variation of temperature, time, methanol-to-oil mole ratio, weight of surfactant, type of surfactant and weight of catalyst, it was possible to perform a multivariate analysis of the process. The most influential variables in the response were the temperature and the weight of the catalyst. Surfactant DBB 7107 was considered better than the surfactant DBB 7104. The optimal conditions were 0.7% w/w of the surfactant DBB 7107, 1 g of KOH, 30 min, methanol to oil mole ratio of 6:1 and temperature equal to 33.5 °C. [ABSTRACT FROM AUTHOR]

A lot of recent research has focused on the study of biocatalysts and nanocatalysts to improve biodiesel production. However, knowledge of the thermodynamic properties of the reaction components is necessary. In this work, the enthalpy of formation and Gibbs free energy of formation for methyl to pentyl esters were calculated using the Gaussian quantum chemistry software (model B3LYP/6-31G(d, p)) and the group contribution method of Constantinou and Gani (MCG). The values obtained by both methodologies present certain differences in relation to the values in the literature. Thus, three correction parameters, which were based on the number of atoms of 26 different molecules, were estimated by minimizing the error function and later used to extrapolate the results to larger molecules of interest. After the use of the correction parameters, the mean deviation between the experimental and calculated values by Gaussian was 0.723% for enthalpy and 1.087% for Gibbs, whereas for MCG, it was 1.324 and 2.540%, respectively. As the methodology proved to be efficient, the thermodynamic properties of the formation of 23 esters that compose the biodiesel were estimated. These properties are of great importance, mainly for the calculation of chemical equilibrium and reaction data in the development of new catalysts. [ABSTRACT FROM AUTHOR]

U ovome preglednom radu opisane su najznačajnije i najčešće primjenjivane jednodimenzijske i dvodimenzijske tehnike NMR u analizi biodizela. Biodizel je ekološki prihvatljivo alternativno gorivo koje se sastoji od zasićenih i nezasićenih metilnih estera masnih kiselina. Budući da analiza kemijskog sastava i proučavanje svojstava biodizela i ostalih biogoriva analitičarima predstavlja izazov, sve više se razvijaju nove i učinkovitije analitičke metode. Spektroskopija NMR jedna je od takvih metoda koja može dati niz informacija o sastavu i strukturi biodizela. Nadalje, analiza spektara NMR pruža vrijedne podatke i o sirovinama iz kojih nastaje biodizel te o procesu esterifikacije. Isto tako primjenom tehnika 1H i 13C NMR može se odrediti sastav aditiva koji se dodaju za sprječavanje rasta mikroorganizama i sastav smjese acetilglicerola i sličnih nusproizvoda sinteze biodizela. U tu svrhu se osim spektara 1H i 13C analiziraju i spektri 31P. U radu su dani karakteristični spektri biodizela, dizela, biljnog ulja tretiranog vodikom te reprezentativan spektar jednog od uzoraka biocida snimljeni u Laboratoriju za spektroskopiju NMR u INA d. d.

Copyright of Gazdalkodas is the property of Herman Otto Intezet Nonprofit Kft. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The manganese carbonate catalyst, prepared by precipitation method, was used in transesterification of soybean oil under subcritical condition of methanol. Catalyst samples were characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS). The triacylglycerol (TAG) conversion and fatty acid methyl esters (FAME) yield were determined using high performance liquid chromatography (HPLC). The transesterification was realized for 1 h using various working conditions: 0-3 wt.% of catalyst (based on the mass of oil), the mole ratio of methanol to oil from 13:1 to 27:1 and temperature ranging from 393 to 473 K. A maximum TAG conversion of 98.1% could be obtained at the optimal reaction conditions: 2 wt.% of catalyst, methanol/oil mole ratio of 21:1, for 1 h in a batch reactor at 453 K. Kinetic analysis showed that the model based on mass transfer and chemical reaction at the catalyst surface confirmed the experimental data. Using that kinetic expression, the effect of continuous transesterification was proposed and verified by a 360-h long realized experiment in a laboratory packed-bed reactor (PBR). Slow deactivation of the catalyst was caused by leaching of Mn in both biodiesel and glycerol phases and by blocking the active sites of the catalyst with organic compounds. [ABSTRACT FROM AUTHOR]

The production of biodiesel esters by transesterification of corn and sunflower oil with methanol has been analyzed using 1,3-bis (isopropylamino)-propan-2-ol catalyst in 15-45mT magnetic field, at 65°C temperature and 6:1 molar ratio of methanol to oil. Experiments were carried out in three-neck round-bottom flask which is placed in magnetic field produced by electromagnets and equipped with a thermometer, a mixer and a dropping funnel. The yield of the biodiesel ester was 95-97% (by mass) and the duration of the process was 4.5 times shorter with magnetic field when the catalyst is used at 3% by weight relative to oil. [ABSTRACT FROM AUTHOR]

Copyright of Military Engineer / Hadmérnök is the property of National University of Public Service and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Biodiesel is an eco-friendly alternative diesel fuel prepared from domestic renewable resources i.e. vegetable oils and animal fats. In this process, biodiesel is produced by transesterification of triglycerides present in animal fat or vegetable oils, by displacing glycerine with a low molar mass alcohol using homogeneous or heterogeneous catalysis. The resulting ester, after mixing with diesel fuels, has physicochemical properties similar to those of conventional fuels. In this work, the batch process of biodiesel production has been studied using tallow fat as raw material with methanol and a heterogeneous catalyst. The quality of the produced biodiesel was evaluated by the determination of important properties, such as viscosity, flash point, cetane number, oxidation stability, glycerine content, acid value, etc. The produced biodiesel was found to demonstrate fuel properties within the ranges recommended by the ASTM D6751. [ABSTRACT FROM AUTHOR]

Copyright of Chemical Industry / Hemijska Industrija is the property of Association of Chemical Engineers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The ethanolysis of sunflower oil catalyzed by calcium oxide was studied in a wide range of reaction conditions: temperature 65-75 °C, ethanol-to-oil mole ratio 6:1-18:1 and catalyst loading 10-20% in order to determine the reaction kinetics. The proposed kinetic model of sunflower oil ethanolysis included the changing and first-order reaction mechanism with respect to triacylglycerols and fatty acid ethyl esters. The kinetic parameters were determined and correlated with the process variables. The Arrhenius equation could be applied to the reaction rate constant with the activation energy of 94.0 kJ/mol. The proposed kinetic model showed a good agreement with the experimental data with a mean relative percentage deviation of ±13% (based on 256 data points). [ABSTRACT FROM AUTHOR]

Vegetable oils are mainly esters of fatty acids and glycerol, which can be converted to fatty acid methyl esters (FAME), also known as biodiesel, by the transesterification reaction with methanol. In order to attain environmental benignity, much attention has been focused in the last decades on utilizing heterogeneous catalysts for biodiesel production instead the homogenously catalyzed transesterification of vegetable oil. The pure CaO or CaO mixed with some other metal oxide due to its low solubility in methanol, FAME and glycerol, low cost and availability, is one of the most promising among the proposed heterogeneous catalysts. Solid catalysts containing CaO usually fulfill a number of important requirements, such as high activity at mild temperature, marginal leaching of Ca cations, long life activity, reusability in transesterification of vegetable oil and easy recovery from the final products of trancesterification (FAME and glycerol). This review is focused on the recent application of pure CaO or CaO in complex catalyst structure and their use as heterogeneous base catalysts for biodiesel synthesis and suitability for industrial application. [ABSTRACT FROM AUTHOR]

The increased production of biodiesel as an alternative fuel involves the simultaneous growth in production of crude glycerol as its main by-product. Therefore, the feasibility and sustainability of biodiesel production requires the effective utilization of crude glycerol. This review describes various uses of crude glycerol as a potential green solvent for chemical reactions, a starting raw material for chemical and biochemical conversions into value-added chemicals, a substrate or co-substrate in microbial fermentations for synthesis of valuable chemicals and production of biogas and biohydrogen, as well as livestock feedstuff. Special attention is paid to various uses of crude glycerol in biodiesel production. [ABSTRACT FROM AUTHOR]

The viscosities of biodiesels of soybean and rapeseed biodiesels blended with mineral diesel fuel were measured at pressures of up to 200 MPa. Using a falling sinker-type viscometer, reproducible viscosity data were obtained based on the time taken for a sinker to descend a fixed distance down an enclosed tube under the influence of gravity. Measurements were taken using pressures corresponding to those of interest in automotive common rail diesel engines, and at temperatures between 25 and 80 °C. In all cases, the viscosity of the biodiesel blends were found to increase exponentially for which the blends were noted as being more viscous than pure mineral fuels. A pressure-freezing effect was not observed for the blends. [ABSTRACT FROM AUTHOR]

Currently, the catalytic efficiency and reusability of the solid base catalysts cannot meet the demand of industrial biodiesel production under low temperature. The purpose of this study is to define the kinetics of heterogeneous transesterification process that could be used for the prediction of the biodiesel synthesis at high temperature and pressure. The focus in this study was paid to recently reported data obtained with different catalysts used for biodiesel synthesis in a batch reactor at high temperatures. It was shown that three kinetic models, including: a) irreversible first order reaction, b) reaction with changeable order and c) resistances of mass transfer and chemical reaction at active sites of the catalyst, could be applied for predicting the effect of high temperature of the transesterification. The apparent reaction rate constant of the irreversible first order reaction was determined, as well as the parameters of the other two, more complicated kinetic models. The best agreement was obtained with the more complicated models and the mean relative percent deviation between calculated and experimentally determined triacylglycerols conversion for these kinetic models is between 3 and 10%. [ABSTRACT FROM AUTHOR]

Copyright of Chemical Industry / Hemijska Industrija is the property of Association of Chemical Engineers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The kinetic model, which was originally developed for sunflower oil methanolysis catalyzed by CaO·ZnO, was examined for several other calcium-based catalysts like neat CaO, quicklime and Ca(OH)2. This model including triacylglycerols mass transfer- and chemically-controlled regimes demonstrated a good agreement with the experimental data in terms of a high coefficient of determination (0.971±0.022) and acceptable mean relative percentage deviation (±15.9%). Hence, this model is recommended for modeling the kinetics of sunflower oil methanolysis over calcium-based catalysts under widely ranging reaction conditions. [ABSTRACT FROM AUTHOR]

In this review, the most important and most frequently used one and two dimensional NMR techniques for biodiesel analysis have been described. Biodiesel is an ecologically accepted alternative fuel consisting of saturated and non-saturated methyl esters of fatty acids. Owing to the fact that analysis of biodiesel chemical composition and properties pose a challenge to analytical chemists, novel and more efficient analytical techniques and methods are being developed constantly. In that respect, NMR spectroscopy is an excellent method, which can provide a wealth of information on the composition and structural properties of biodiesel. NMR can be used for determination of the iodine value of biodiesel, fatty acid profile, and percentage of fatty acid methyl esters. Furthermore, NMR spectral analysis can give valuable data on raw materials used for biodiesel production and the process of trans-esterification can be monitored. By the application of 1H and 13C NMR techniques, the composition and structure of additives for preventing the growth of microorganisms can be determined. For that purpose, apart from 1H and 13C spectra, 31P spectra are used as well. Also, composition of acetylglycerol mixtures and corresponding by-products of biodiesel synthesis can be analysed. NMR spectroscopy has proven useful in analysis of hydrotreated vegetable oils, which have better fuel properties than biodiesel produced via transesterification, and their application improves engine fuel economy. In this paper, representative NMR spectra of diesel, biodiesel and hydrotreated vegetable oil and those of biocide samples recorded in the Laboratory for NMR spectroscopy of INA d. d. are given. The advantages of using NMR spectroscopy in biodiesel analysis and determination of its properties are discussed. [ABSTRACT FROM AUTHOR]

Copyright of Technical Journal / Tehnički Glasnik is the property of Polytechnic of Varazdin and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Kao obnovljivo i alternativno gorivo, biodizel je u posljednjih petnaestak godina predmet brojnih istraživanja, između ostalog i ispitivanja utjecaja na performance motora i motornih ulja. Upotreba biodizela ima cijeli niz prednosti, međutim, biodizel pokazuje i neke nedostatke koji su uočeni njegovom primjenom. Primjenom biodizela dolazi do njegovog akumuliranja u ulju, a time i do razrjeđenja ulja. Prekomjerno razrjeđenje ulja može stvoriti probleme pri radu motora. Zbog akumuliranja biodizela u ulju dolazi do pada viskoznosti ulja, stvaranja povećane količine oksidacijskih produkata, taloga i pogoršanja niskotemperaturnih osobina. Pored toga, razrjeđenje motornog ulja može utjecati na skraćenje intervala zamjene ulja, efikasnost djelovanja paketa aditiva, kao i pojačanu koroziju, i to prije svega obojenih metala. U ovom radu je praćen utjecaj biodizela na kvalitetu motornog ulja kod provođenja visokotemperaturnog motornog testa. Za ispitivanje je korišteno motorno ulje viskozitetne gradacije SAE 15W-40. Ispitivano motorno ulje ispunjava zahtjeve o kvaliteti vodećih proizvođača motora, kao što su: MB, MAN, VOLVO. Ispitivanje je obavljeno na motoru uz točno definirane uvjete rada. Kao pogonsko gorivo je korištena mješavina dizela i biodizela. Paralelno je ispitivan utjecaj biodizela na koroziju obojenih metala (Pb, Cu, Sn), kao i utjecaj biodizela na procese oksidacije ulja. [ABSTRACT FROM AUTHOR]

The kinetics of heterogeneous methanolysis of sunflower oil was studied at 60 °C using mechanochemically synthesized CaO⋅ZnO as catalyst. The influence of agitation speed, catalyst amount, and methanol-to-oil molar ratio on the rate of reaction was analyzed. The rate of the process depends on the two resistances -- mass transfer of triglycerides to the catalyst surface and chemical reaction on the catalyst surface, which are defined as the values of the overall triglyceride volumetric mass transfer coefficient, kmt,TG, and the effective pseudo first-order reaction rate constant, k, respectively. These kinetic parameters actually determine the value of the apparent reaction rate constant, kapp, the time dependence of which is defined by the change of triglyceride (TG) conversion. A kinetic model is proposed and the model parameters are determined. [ABSTRACT FROM AUTHOR]

Copyright of Afyon Kocatepe University Journal of Science & Engineering / Afyon Kocatepe Üniversitesi Fen Ve Mühendislik Bilimleri Dergisi is the property of Afyon Kocatepe University, Faculty of Science & Literature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Agricultural Sciences, Belgrade is the property of University of Belgrade, Faculty of Agriculture and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Agricultural Sciences, Belgrade is the property of University of Belgrade, Faculty of Agriculture and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chemical Industry / Hemijska Industrija is the property of Association of Chemical Engineers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Energy costs are the key characteristic of any industrial plant, so that adequate importance should be given to the heat balances calculations at its design stage. The precondition for corresponding calculations is the knowledge of heat properties of reaction system components. To that end, this paper presents data on the heat capacities of vegetable oils and biodiesel. Particular importance has been given to the biodiesel components data, which are fully presented here for the first time. The heat of transesterification reaction calculation is presented here for the first time as well. The heat balances of separate production process phases are delineated. The advances in production technologies and process unit development are also described. [ABSTRACT FROM AUTHOR]

Transesterification of vegetable oils or fats in the conventional industrial process of biodiesel production results in the mixture of products, which requires particular treatment procedures. In this part of the paper, first the property of the reaction product phases then the characteristics of the separation process are delineated. The kinetics of the transesterification is briefly presented afterwards. Particular emphasis is given to the yield calculations for various vegetable oils. The basics of mass balances calculations of the entire process including reaction components and the products of two-stage transesterification are presented, including biodiesel and by-products purification system. [ABSTRACT FROM AUTHOR]

The common industrial process of biodiesel production is a sequence of particular unit operations starting with raw material preparation, followed by transesterification reaction stage and ending with reaction mixture separation and treatment. The main product is biodiesel of prescribed quality while the treatment of glycerol and salt containing phase is carried out so that the by-products obtained maximize profitability of the entire undertaking. The biodiesel production process is often analysed by people of various profiles without proper engineering backgrounds, so that qualitative descriptions are prevailing in the literature. Opposite to that approach, promoted in this paper are the chemical engineering aspects of biodiesel production technology. That approach has not attracted adequate attention so far despite the eminently chemical engineering nature rather than the chemical nature of that process. This will be elaborated in a three-part series. In this, the first one, the necessity of replacing fossil fules with renewable fuels is explained and the biodiesel production put into that context. In particular, the characteristics of industrial biodiesel production are delineated along with the physical and chemical characteristics of homogeneously catalysed transesterification. The systematic approach to the scale-up procedure is described as well. [ABSTRACT FROM AUTHOR]

Complex chemical composition and physical properties of oil and fuel make their complete characterization very difficult. Components present in oil and oil products differ in structure, size, polarity and functionality. The presence and structure of specific hydrocarbons in final products depend on the processing procedure and type of the fuel. In order to predict or improve fuel properties it is necessary to determine its composition. Thus, new and more sophisticated analytical methods and procedures are constantly being developed. NMR spectroscopy plays a significant role in analysis and identification of complex hydrocarbon mixtures of petroleum and petroleum products. In this review, we describe the application of NMR spectroscopy for analyzing gasoline and diesel fuels. Hence, by using NMR spectroscopy it is possible to determine gasoline composition and presence of benzene and oxygenates, as well as some important physical characteristics of gasoline such as the research octane number. An application of different NMR techniques made it possible to characterize diesel fuels and middle oil distillates from various refineries. Data so obtained can be used in combination with statistical methods to predict fuel properties and to monitor production processes in the petroleum industry. NMR spectroscopy has proven useful in analysis of FAME which has recently been used as an ecologically acceptable alternative fuel. Furthermore, techniques such as CP/MAS for characterization of solid state oil-geochemical samples are included. Also, possibilities of using NMR spectroscopy in the analysis of polymeric additives are discussed. [ABSTRACT FROM AUTHOR]

Copyright of Chemical Industry / Hemijska Industrija is the property of Association of Chemical Engineers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chemical Industry / Hemijska Industrija is the property of Association of Chemical Engineers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Ultrasound-assisted sunflower oil methanolysis catalyzed by KOH was studied to define a simple empirical kinetic model useful for reactor design without complex computation. It was assumed that the neutralization of free fatty acids and the saponification reactions were negligible. The methanolysis process rate was observed to be controlled by the mass transfer limitation in the initial heterogeneous regime and by the chemical reaction in the later pseudo-homogeneous regime. A model featuring irreversible second-order kinetics was established and used for simulation of the triacylglycerol conversion and the fatty acid methyl esters formation in the latter regime. Good agreement between the proposed model and the experimental data in the chemically controlled regime was found. [ABSTRACT FROM AUTHOR]

The growing demand of freight transportation and passenger cars has led to air pollution, green house gas emissions (especially CO2) and fuel supply concerns. Research has been carried out on biodiesel which is shown to generate lower emissions. However, the amount of emissions generated is not well understood which entails more vigorous data collection and development of emissions models. A comprehensive data collection plan was developed and emissions (NOx, HC, CO, CO2 and PM10) from biodiesel fueled transit buses were collected using a portable emissions measurement system (PEMS). Linear models were developed and tested for each emission. However, the models could not capture the emissions spikes well resulting in very low R values. Artificial neural networks (ANNs) based models were then employed on this data because of their ability to handle nonlinearity and not requiring assumptions on the input data as needed by statistical models. Sensitivity analysis was performed on the input parameters, number of hidden layers, learning rate and learning algorithm to arrive at an optimum ANN architecture. he optimal architecture for this study was found to be two hidden layers with 50 hidden nodes for each of NOx, HC, CO, and PM and one hidden layer for CO2. he emissions were predicted using best-performance ANN models for each emission. Scater-plots of observed versus predicted values showed R of 0.96, 0.94, 0.82, 0.98 and 0.78 for NOx, HC, CO, CO2 and PM emissions, respectively. Histogram on prediction error showed low frequency for large errors. [ABSTRACT FROM AUTHOR]

In this study, local vegetable oil named as Ricinus Communis (RC) is used as the raw material for the production of biodiesel. In order to obtain RC oil, Soxhalet Extraction apparatus was used. This paper deals with the transesterification of Ricinus Communis oil with methanol to produce biodiesel. Moreover, this study analysis the fuel properties of RC biodiesel and soybean biodiesel blends. Various properties of the RC biodiesel, Soybean biodiesel and their blends such as the cold filter plugging point (CFPP), cetane number, flash point, kinematic viscosity and density were determined. Test results were compared well with European biodiesel standards EN 14214. Analysis showed that the cetane number and the cold flow behavior of the RC biodiesel and soybean biodiesel blends were improved due to the high cetane number (80) and the low cold filter plugging point (-35 °C) of RC biodiesel. [ABSTRACT FROM AUTHOR]