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Residues from the wine industry constitute an abundant feedstock for biodiesel production in wine-producing countries. The use of grapeseed oil, together with bioethanol obtained from distillation of wine surplus or grape skins and stalks and wine lees, as reagents in the transesterification reaction, results in a mixture of fatty acid ethyl esters (FAEE), which is a fully renewable, autochthonous, and waste-derived biofuel. In this work, a blend of FAEE produced from grape seed oil with diesel fuel was selected based on a study of fuel properties, and the optimal blend, with 30% v/v of FAEE, was tested in a Euro 6 engine following the Worldwide harmonized Light-duty Test Cycle (WLTC) and a Real Driving Emissions Cycle (RDE), as required in the new certification procedures. Engine performance and emissions from this blend and a commercial diesel fuel were compared. The FAEE blend showed a significant potential to reduce particle emissions, both in mass and number (from 23% in number to 46.5% in mass for WLTC, and from 56% in number to 61% in mass for RDE), and CO (25.5% for WLTC and 39% for RDE) but penalized NOx (32% higher in WLTC and 26.4% higher in RDE).
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Many concerns, such as economic and technical viability and social and ethical aspects, must be considered for a feedstock selection for advanced biofuels. Industrialized countries promote the use of industrial waste or by-products for this purpose. In particular, turpentine has several properties which make it an attractive source for biofuels, including its possible industrial waste origin. Nevertheless, turpentine has shown some disadvantages when blended directly with diesel, especially because it increases the sooting tendency. On the contrary, some derivatives of turpentine can be suitable for diesel blends. Thus, the evaluation of their properties is necessary. In the present work, the properties of hydrogenated and oxyfunctionalized turpentine have been analysed and compared with the purpose of elucidating their benefits and drawbacks in diesel fuel applications, using European standards as a reference. The results show a promising application of both hydroturpentine and oxyturpentine as diesel components. While hydroturpentine significantly improves the diesel cold flow properties, oxyturpentine noticeably reduces the sooting tendency.
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ABSTRACT: In Europe, recent regulations on advanced biofuels have prompted a search for new fuel sources and the development of synthesis methods meeting the demanding specifications of the sector. However, in developing countries such as Algeria, where a significant stock of frying oil is unused, the use of diesel engines powered with waste-oil-derived biofuels must be explored. In this work, the variables related to the transesterification reaction from this frying oil with ethanol are analyzed using response surface methodology. From this analysis, only the reaction time and temperature have been determined as relevant parameters. In addition, FT-IR analysis has proven a useful tool to analyse the conversion in the transesterification reaction of waste frying oil with ethanol and is cheaper and quicker than GC-FID. This sustainable biofuel (FAEE), mixed with a diesel and pure fuel, has been physically characterized. The mixture of FAEE at 30% by volume with diesel meets the requirements demanded in standard EN 590 and can be classified as winter diesel class D. As a pure biofuel, only its high cold flow temperatures could constitute a drawback for exporting to temperate climates but not for internal consumption.
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Wine industry generates a large amount of biowaste, such as grape marc and wine lees, which is considered in the Directive (EU) 2018/2001 as an adequate feedstock to produce advanced biofuels. Grapeseed oil fatty acid ethyl esters (FAEEs) can be obtained from oil extracted from grape marc and bioethanol distilled from wine lees or wine surplus. Although FAEE still has no specific standard, grapeseed oil FAEE would fulfill all of the properties set by the standard EN 14214, except oxidation stability. This work analyzes the effect of natural antioxidants on the oxidation stability of grapeseed oil FAEE, using grapeseed oil fatty acid methyl esters (FAMEs) as a reference for comparison. On the one hand, the biofuel, produced with conventional transesterification, was mixed with FAME and FAEE produced via in situ transesterification. On the other hand, antioxidants extracted from grapeseed or defatted grapeseed flour were added to the biofuel. The results show that (1) FAEE has worse oxidation stability than FAME, (2) in situ transesterification improves the oxidation stability, and (3) addition of natural antioxidants is hindered by their low solubility in alkyl esters. Finally, the concentration of antioxidants, measured by UV-vis spectroscopy, showed a correlation between the absorbance at 285 nm (characteristic of phenolic compounds) and the induction time (IT) of the samples.
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The purpose of this research is to find a mathematical model based on a statistical analysis to predict the evolution of the total petroleum hydrocarbons (TPH) concentrations with time in the bioremediation process of diesel contaminated soils. The analysis is useful to compare and ascertain the efficiency of different remediation treatments and the influence of both soil characteristics and initial concentration levels of hydrocarbons on the biodegradation process. An experimental design, considering two types of soil, two concentration levels of hydrocarbons and six different amendments was carried out. A total of 336 laboratory tests were conducted during a year in 48 land plots of 4×4m, spreading over eight field campaigns. The results show, for the first time to the best of our knowledge, that the bioremediation process can be adjusted quantitatively to an exponential model, following a first-order kinetic equation. The model explains correctly the higher efficiency of some treatments. In the case of hydrocarbon concentrations <16,000mg/kg, it is advisable to use slow-release fertilizer without the use of surfactant; whereas, for concentrations above 30,000mg/kg, the addition of surfactants improves the results considerably.
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Biodegradação Ambiental , Petróleo/análise , Poluentes do Solo/análise , Modelos Lineares , Petróleo/metabolismo , Poluentes do Solo/metabolismoRESUMO
Zeolitic tuff constitutes a technical and economical feasible alternative to manage acidic waters in initial phases of generation. A study of cation exchange with two zeolitic tuffs from Ecuador and one from Cuba has been conducted using breakthrough curve methodology. Cations Mn2+, Cd2+, Cr3+, Zn2+, and Al3+ have been chosen owing to their presence in underground water in exploration activities (decline development) in Fruta del Norte (Ecuador). Zeolites characterized by X-ray diffraction and thermal stability after heating overnight as heulandites show a similar exchange behavior for the five cations studied. The clinoptilolite sample Tasajeras shows a relevant cation exchange performance expressed in the important increment of spatial time to reach the breakthrough point in comparison with heulandite samples. The maximum length of unused beds was found for Cr3+ and Zn2+ cations showing, therefore, a lower adsorption performance in relation with Mn2+ and Cd2+. A final disposal method of metal-loaded zeolites with cement is proposed.
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Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Zeolitas/química , Zinco/isolamento & purificação , Adsorção , Alumínio/isolamento & purificação , Cádmio/isolamento & purificação , Cromo/isolamento & purificação , Cuba , Equador , Manganês/isolamento & purificação , MineraçãoRESUMO
Polycyclic Aromatic Hydrocarbons (PAHs) are pollutants of concern due to their carcinogenic and mutagenic activity. Their emissions are mainly related with the combustion or pyrolysis of the organic matter, such as in fossil fuels combustion. It is important to characterize PAHs in the combustions of biofuels due to their increasing importance in the actual energetic setting. There is a lot of research focused in PAHs emission due to the combustion in diesel engines; but only few of them have analyzed the effect of raw material and type of alcohol used in the transesterification process. Different raw materials (i.e. animal fat, palm, rapeseed, linseed, peanut, coconut, and soybean oils) have been used for obtaining FAME and FAEE. A method for measuring PAHs generated during combustion in a bomb calorimeter has been developed. Combustion was made at different oxygen pressures and the samples were taken from the bomb after each combustion. Samples were extracted and the PAHs amounts formed during combustion were analyzed by GC-MS. This research shows the statistical relationships among the 16 PAHs of concern, biodiesel composition and oxygen pressure during combustion.
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A study of breakthrough curves for cations usually found in acid mine drainage (Pb(2+), Cu(2+), Zn(2+) and H(+)) and municipal wastewater (NH(4)(+)) have been conducted on some natural zeolitic tuffs. The zeolitic tuffs used in this study are: three zeolitic tuffs from Cayo Formation, Guayaquil (Ecuador), characterized by X-ray diffraction as clinoptilolite (sample CLI-1) and heulandite (samples HEU-1 and HEU-2)-rich tuffs, and two zeolitic tuffs from Parnaiba Basin, Belem do Pará (Brazil), characterized as stilbite-rich tuffs (samples STI-1 and STI-2). The clinoptilolite sample CLI-1 shows an exceedingly good exchange capacities for Pb(2+) and NH(4)(+) as received, and also a very high exchange capacity for Cu(2+) and Zn(2+) when conditioned with 2M sodium chloride, with much higher values than those reported in the literature for other clinioptilolite ores. A general order of effective cation exchange capacity could be inferred from breakthrough curves on these zeolitic tuffs: CLI-1 > HEU-2 > HEU-1 > STI-2. Since it is true for most of the cations studied.