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The effects of Cd, Ni, Cu, or Zn on the whole cell-derived fatty acid profiles of four bacterial strains isolated from heavy metal-polluted soils located in Upper Silesia was determined. Based on the fatty acid methyl ester (FAME) profiles, the strains were identified and named as Enterobacter intermedius AM15, Enterobacter intermedius MH8b, Pseudomonas putida MH1d, and Klebsiella pneumoniae AM12. The obtained results showed changes that were dependent both on tested strains and metal used. The most significant changes were observed for strains cultured in the Ni presence. In the FAME profiles of MH8b, AM15, and AM12 strains, a significant increase of cyclopropane fatty acids was observed. Moreover, exposure for Ni resulted in the appearance of a new fatty acid in the FAME profiles of AM15 and MH8b strains. In turn, Cd and Zn caused a decrease of the content of cyclopropane fatty acids as compared to control. For AM15 and AM12 strains cultured on media with heavy metals, the ratio of saturated to unsaturated fatty acids were higher than that in control. The same phenomenon was also observed for MH8b strain exposed only to the highest concentration of Ni and Cd.
The aim of this work was to examine possibilities to use wastes of animal fat and vegetable oil for the production of biodiesel fuel, evaluating the conformity of the product obtained to the oxidation stability requirements. The oxidation stability of rapeseed oil, linseed oil, tallow and lard fatty acid methyl esters samples and their mixtures was measured by commercial equipment Rancimat 743 applying accelerated oxidation test (Rancimat test) specified in EN 14112. It was found that fatty acid methyl esters of vegetable origin are more stable for oxidation comparing with methyl esters of animal origin. The optimal level of synthetic antioxidants such as butylated hydroxyanizole (BHA) and butylated hydroxytoluene (BHA) for stabilization of fatty acid methyl esters was determined to be 400 ppm (also using synergist – citric acid, 20% of the antioxidant quantity). Mixtures of methyl esters of animal and vegetable origin with antioxidants were more stable compared with pure products. The highest oxidation stability showed mixtures containing 80-90% of fatty acid methyl esters of animal fat and 10-20% of fatty acid methyl esters of vegetable oil with synthetic antioxidants added.
This work presents a concept of waste technical fats processing into surfactants of gemini type based on the utilization of methyl esters of long chain fatty acids. The method of such esters ketonization has been elaborated upon. Ketones obtained in this way can be processed using reductive amination. Long chain amines can be used for the production of nonionic surfactants in the condensation with aldoses and hydrogenation or in condensation with oxidized sugars.
Soot and hydrocarbons are usually found in diesel exhaust gases. They are formed when the fuel is burnt out incompletely. Polycyclic aromatic hydrocarbons (PAH) are sorbed on the soot, and may cause cancerous diseases, asthma and other diseases. The purpose of this work was to evaluate the dependence of smoke opacity and amount of polycyclic aromatic hydrocarbons in engine emissions on multi-component biodiesel fuel composition. We analyzed the composition of exhaust gases when diesel engine was fuelled with rapeseed oil methyl esters (RME ), RME mixtures with linseed oil methyl esters (LSME ) and fatty acid methyl esters (FA ME) of animal origin, assessing the smoke opacity and qualitative and quantitative composition of PAH. It was determined that smoke opacity of exhaust gases decreases at different rotation speeds (1200 and 2000 min⁻¹) when the amount of FA ME, containing a greater amount of saturated fatty acids, is increasing. Total PAH concentration in exhaust gases of biofuel mixtures with pork lard fatty acid methyl esters (LME ) is lower than in the case of mixtures with beef tallow fatty acid methyl esters (TME ). The amount of PAH at a rotation speed of 1200 min⁻¹ reduced down to 57%, if compared to pure RME , and down to 30%, when the rotation speed was 2000 min⁻¹. In the exhaust gases of biofuel mixtures with pork lard fatty acid methyl esters there are fewer PAHs with highly expressed mutagenic and carcinogenic effects if compared to pure RME and its mixtures, containing tallow fatty acid methyl esters. The most effective from an environmental point of view is use of a fuel mixture containing 80% RME , 4% LSME and 16% LME.
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