Open AccessReproducibility of PetroOxy and its correlation with the Rancimat method
Author(s) -
Karolína Jaklová,
Aleš Vráblík
Publication year - 2020
Publication title -
paliva
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.111
H-Index - 1
ISSN - 1804-2058
DOI - 10.35933/paliva.2020.03.03
Subject(s) - en 14214 , biodiesel , diesel fuel , pulp and paper industry , biofuel , chemistry , environmental science , waste management , organic chemistry , biodiesel production , engineering , catalysis
The current trend of reducing greenhouse gas emissions and carbon footprint as well as legislation requirements means an increase in the effort to replace fossil fuels by using renewable sources. One of the possibilities is usage of methyl esters (FAME or UCOME) as a bio-component in diesel fuel. Now the maximum FAME content in diesel is 7 vol% (according to the standard EN590 – B7). Increasing the proportion of FAME means a deterioration in oxidation stability. FAME is produced by the transesterification of the triglycerides present in vegetable oils. A major disadvantage of biodiesel (FAME) is ability to be slowly oxidised by air oxygen. Oxidation products may impair fuel properties, quality and engine performance. This is the reason why the oxidation stability of diesel and biodiesel is an important quality parameter. It could be detected using several methods, for example: Rancimat, PetroOxy or thermal techniques.The Rancimat method is intended for biodiesel and for diesel with a minimum 2 vol% content of FAME as mentioned in the standards EN 590 and EN 14214. The disadvantage is the time required for this method (more than 8 h for biodiesel and 20 h for diesel).The PetroOxy is shorter and its results can be converted to Rancimat stability.The set of 75 samples (40 samples of B7 and 35 samples of FAME) was measured using both mentioned methods. Three values of oxidation stability were determined for all of the analysed samples. In the first laboratory, oxidation stability of the samples was measured using both methods. In the second laboratory, oxidation stability was measured using only the PetroOxy. The PetroOxy results from both laboratories were compared with a high correlation value (R2 = 0,954). In the next step, outliers were removed from dataset. Experimental results of the Rancimat method were correlated with recalculated values of PetroOxy method from both laboratories. Correlation equation provided by the manufacturer of PetroOxy was used for recalculation of PetroOxy results to Rancimat results at first. Measured results were then compared with recalculated results. The largest difference in results was found in the B7 samples.Because of these differences the correlation equation between PetroOxy and Rancimat was optimized. Two different equation were made (for each laboratory). The recalculated oxidation stability results were compared with the primary results from Rancimat. The newly correlated values showed a higher degree of agreement with the experimental data than when the results were recalculated using the correlation equation provided by manufacturer.These optimized correlation equation have proven to be more suitable for industrial laboratories.