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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.

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]