APPLICATION OF COMPLEX INSTRUMENTAL TECHNIQUES, SPECTROSCOPY AND CHROMATOGRAPHY, FOR THE ANALYSIS OF BIOFUELS AND BIOMASS

Biofuels are environmentally friendly alternative fuels produced from animal and plant raw materials. They have great significance due to limited availability of crude oil and increased ecological requirements. The development of biofuels is followed by the development of new and more efficient analytical procedures for monitoring the composition and physical-chemical properties. This paper presents the application of chromatographic and spectroscopic methods in the analysis of different types of biofuels. The results of the determination of the hydrocarbon composition and functional groups important for the application of biofuels as blending components are shown. In this paper, it has confirmed the possibility of using NMR spectroscopy, HPLC and IC chromatography in biofuel and biomass analysis

Application of NMR Spectroscopy in the Analysis of Biodiesel

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

NMR Spectroscopy as a Tool for Studying Asphaltene Composition

Asphaltenes are the most polar oil components with molecular weights between 500 and 1000 Da, which primarily consist of carbons and hydrogens, some heteroatoms, such as nitrogen, sulphur, oxygen and traces of nickel, vanadium and iron. Owing to their extreme complexity, it is almost impossible to completely identify all the compounds present in asphaltene samples. Various analytical techniques and approaches were used to characterize asphaltenes but their structure and composition are still a matter of thorough investigations. NMR spectroscopy can reveal useful information on asphaltene molecular architecture and aggregation process. In that respect, one- and two-dimensional NMR techniques have widely been employed. Although NMR spectra of these complex mixtures are difficult to interpret, they still can provide valuable data, especially in combination with statistical methods. Some distinctive examples of using NMR spectroscopy to study asphaltenes are given in this review. This work is licensed under a Creative Commons Attribution 4.0 International License

The Use of 13C NMR Spectroscopy and Comprehensive Two-dimensional Gas Chromatography, GC×GC, for Identification of Compounds Involved in Diesel Fuel Oxidative Behavior

An approach has been proposed combining one dimensional inverse gated 13C NMR spectroscopy and a comprehensive two dimensional gas chromatography (GC×GC) to analyze diesel fuels prior and after oxidation under the standard conditions. Classes of hydrocarbons present before and after oxidation have been identified and quantified. A decrease in aromatic iso- and n-paraffinic hydrocarbons and an increase in the total saturated hydrocarbons have been observed after oxidation. In that respect NMR spectroscopy has potential to be used as standard method for determination of oxidation stability. Furthermore, GC×GC has been applied to identify compounds involved in the formation of sediments during oxidation. Obtained results have shown that hydrocarbon composition, especially the normal paraffin content play a role in the formation of sediments in these distillate fuels. This is important since sediments may influence the quality of diesel fuels. (doi: 10.5562/cca1874

Advanced analytical techniques - supporting the development of biofuels and alternative fuels

Potreba za razvojem alternativnih goriva i biogoriva potencirana je potrebom smanjenja utjecaja globalnog zagrijavanja i klimatskih promjena na planet te ograničenim resursima sirove nafte i prirodnog plina. Zadnjih godina pojavljuje se niz različitih vrsta biogoriva i alternativnih goriva različitog porijekla. Biogoriva su ekološki prihvatljiva alternativna goriva proizvedena od životinjskih i biljnih sirovina, a u svrhu razvoja biogoriva koriste se otpadni materijali iz proizvodnje drva, otpadne sirovine životinjskog porijekla, otpadna jestiva ulja te sirovine biomasa poput biljke Miscanthusa X giganteus, kukuruza, zobena slama, pšenična slama, soja, ječam i dr. Razvoj novih vrsta goriva prati razvoj novih i učinkovitijih analitičkih postupaka za praćenje sastava i svojstava. Stoga se često pri analizi biogoriva i alternativnih goriva koriste spektroskopske i kromatografske metode, samostalno ili u kombinacijama s drugim ispitnim metodama. Prednosti ovih metoda su velika osjetljivost, selektivnost i preciznost.The need to develop alternative fuels and biofuels has become essential regarding the need for reducing the impact of global warming and climate change on the planet as well as the limited resources of crude oil and natural gas. In recent years, different types of biofuels and alternative fuels of different origins have been developed. Biofuels are environmentally friendly alternative fuels produced from animal or plant origins. For biofuel development different materials like waste materials from wood production, waste raw materials of animal origin, waste edible oils and biomass raw materials such as miscanthus X giganteus, corn, oat straw, wheat straw, soybeans, barley are used. The development of new types of ecological friendly fuels goes with the development of new and more efficient analytical procedures for both monitoring the fuel composition and properties. Spectroscopic and chromatographic methods, either alone or in combination with other test methods, are often used in the analysis of biofuels and alternative fuels. The advantages of these methods are sensitivity, selectivity, and precision

Advanced analytical techniques - supporting the development of biofuels and alternative fuels

Potreba za razvojem alternativnih goriva i biogoriva potencirana je potrebom smanjenja utjecaja globalnog zagrijavanja i klimatskih promjena na planet te ograničenim resursima sirove nafte i prirodnog plina. Zadnjih godina pojavljuje se niz različitih vrsta biogoriva i alternativnih goriva različitog porijekla. Biogoriva su ekološki prihvatljiva alternativna goriva proizvedena od životinjskih i biljnih sirovina, a u svrhu razvoja biogoriva koriste se otpadni materijali iz proizvodnje drva, otpadne sirovine životinjskog porijekla, otpadna jestiva ulja te sirovine biomasa poput biljke Miscanthusa X giganteus, kukuruza, zobena slama, pšenična slama, soja, ječam i dr. Razvoj novih vrsta goriva prati razvoj novih i učinkovitijih analitičkih postupaka za praćenje sastava i svojstava. Stoga se često pri analizi biogoriva i alternativnih goriva koriste spektroskopske i kromatografske metode, samostalno ili u kombinacijama s drugim ispitnim metodama. Prednosti ovih metoda su velika osjetljivost, selektivnost i preciznost.The need to develop alternative fuels and biofuels has become essential regarding the need for reducing the impact of global warming and climate change on the planet as well as the limited resources of crude oil and natural gas. In recent years, different types of biofuels and alternative fuels of different origins have been developed. Biofuels are environmentally friendly alternative fuels produced from animal or plant origins. For biofuel development different materials like waste materials from wood production, waste raw materials of animal origin, waste edible oils and biomass raw materials such as miscanthus X giganteus, corn, oat straw, wheat straw, soybeans, barley are used. The development of new types of ecological friendly fuels goes with the development of new and more efficient analytical procedures for both monitoring the fuel composition and properties. Spectroscopic and chromatographic methods, either alone or in combination with other test methods, are often used in the analysis of biofuels and alternative fuels. The advantages of these methods are sensitivity, selectivity, and precision

THE ROLE AND IMPORTANCE OF CHROMATOGRAPHY AND SPECTROSCOPY IN THE ANALYSIS OF NONCONVENTIONAL FUELS

Nekonvencionalna goriva sve više dobivaju na značaju zbog ograničene raspoloživosti sirove nafte i naglog rasta automobilske industrije i transportnog sektora što je rezultiralo povećanjem emisija ispušnih plinova u okoliš. Ispušni plinovi koji nastaju izgaranjem fosilnih goriva korištenih u transportnom sektoru smanjuju kvalitetu zraka i time utječu direktno na ljudsko zdravlje. Biogoriva su ekološki prihvatljivija alternativna goriva koja se dobivaju iz sirovina životinjskog i biljnog porijekla. Sve se više razvijaju nove i učinkovitije analitičke metode s obzirom da poznavanje kemijskog sastava predstavlja izazov analitičarima. U ovome radu prikazane su najčešće i najznačajnije kromatografske i spektrometrijske metode u analizi sirovina i nekonvencionalnih goriva. U radu su prikazani karakteristični kromatogrami i spektri pojedinih sirovina za proizvodnju biogoriva i kromatogrami biodizela snimljeni u Laboratoriju za ispitivanje voda, ugljikovodika i materijala (Služba Centralni ispitni laboratorij) u INA Industrija nafte d.d.Nonconventional fuels are gaining in importance due to limited availability of crude oil and rapid growth of the automotive industry and transportation sector which is resulting in increased emissions into the environment. Exhaust gases associated with combustion of fossil fuels used in transportation sector reduce air quality and thus have direct impact on human health. Biofuels are more environmentally friendly alternative fuels that are produced from animal or vegetable feedstocks. Developments of new and more effective analytical methods are increasing since the knowledge of the chemical composition represents challenge to analysts. In this paper, the most common and important chromatographic and spectroscopic methods in the analysis of feedstocks and nonconventional fuels are shown. The paper also presents the characteristic chromatogram and spectra of certain feedstocks for biofuel production and chromatogram of biodiesel recorded in the Laboratory for testing, water, hydrocarbons and materials (Central Testing Laboratory Department) in INA Petroleum Industry

NMR and Chemometric Characterization of Vacuum Residues and Vacuum Gas Oils from Crude Oils of Different Origin

NMR spectroscopy in combination with statistical methods was used to study vacuum residues and vacuum gas oils from 32 crude oils of different origin. Two chemometric metodes were applied. Firstly, principal component analysis on complete spectra was used to perform classification of samples and clear distinction between vacuum residues and vacuum light and heavy gas oils were obtained. To quantitatively predict the composition of asphaltenes, principal component regression models using areas of resonance signals spaned by 11 frequency bins of the 1H NMR spectra were build. The first 5 principal components accounted for more than 94 % of variations in the input data set and coefficient of determination for correlation between measured and predicted values was R2 = 0.7421. Although this value is not significant, it shows the underlying linear dependence in the data. Pseudo two-dimensional DOSY NMR experiments were used to assess the composition and structural properties of asphaltenes in a selected crude oil and its vacuum residue on the basis of their different hydrodynamic behavior and translational diffusion coefficients. DOSY spectra showed the presence of several asphaltene aggregates differing in size and interactions they formed. The obtained results have shown that NMR techniques in combination with chemometrics are very useful to analyze vacuum residues and vacuum gas oils. Furthermore, we expect that our ongoing investigation of asphaltenes from crude oils of different origin will elucidate in more details composition, structure and properties of these complex molecular systems

USE OF BIO-COMPONENTS IN CATALYTIC CRACKING PROCESS

U procesu fluid katalitičkog krekiranja moguće je kao udio u standardnoj FCC sirovini koristiti različite vrste biokomponenti kao što su sve vrste jestivih ulja (suncokretovo, repičino, palmino ulje) te otpadna jestiva ulja. U radu je kao sirovina korišteno otpadno suncokretovo ulje koje se dodavalo standardnoj FCC sirovini u iznosu od 10 % v/v i 20 % v/v. Ispitivanja prinosa i raspodjele produkata načinjena su testom mikroaktivnosti te su dobiveni rezultati uspoređeni s prinosima i produktima dobivenim iz standardne FCC sirovine. U radu je korišten ravnotežni komercijalni katalizator iz FCC jedinice iz naših rafinerija. Pokazano je kako se korištenjem biokomponenti kao komponenti standardne FCC sirovine mogu zadovoljiti zahtjevi za korištenje biogoriva u cestovnom transportu te omogućiti kvalitetno zbrinjavanje otpadnih jestivih ulja bez velikih dodatnih troškova.Various types of bio-components, such as all types of edible oils (sunflower, rape, palm), used edible oils may be used in the fluid catalytic cracking process as part in standard FCC feed. In this work, the used sunflower oil was chosen as a feed added to the standard FCC feedstock in the quantity of 10 v/v % and 20 v/v %. Testing of yield and distribution of products (gas components, LPG, FCC gasoline, light cyclic oil, heavy cyclic oils, and coke) has been performed by the micro-activity test and the obtained results have been compared with the yields and products obtained from the standard feedstock. The equilibrium zeolite catalyst from the commercial FCC unit was used. It was shown how the use of bio-components as the standard FCC feed has been proven to meet the requirements for use of bio-fuels in road transportation, as well as to provide a quality disposal of used edible oils without high added costs

USE OF BIO-COMPONENTS IN CATALYTIC CRACKING PROCESS

U procesu fluid katalitičkog krekiranja moguće je kao udio u standardnoj FCC sirovini koristiti različite vrste biokomponenti kao što su sve vrste jestivih ulja (suncokretovo, repičino, palmino ulje) te otpadna jestiva ulja. U radu je kao sirovina korišteno otpadno suncokretovo ulje koje se dodavalo standardnoj FCC sirovini u iznosu od 10 % v/v i 20 % v/v. Ispitivanja prinosa i raspodjele produkata načinjena su testom mikroaktivnosti te su dobiveni rezultati uspoređeni s prinosima i produktima dobivenim iz standardne FCC sirovine. U radu je korišten ravnotežni komercijalni katalizator iz FCC jedinice iz naših rafinerija. Pokazano je kako se korištenjem biokomponenti kao komponenti standardne FCC sirovine mogu zadovoljiti zahtjevi za korištenje biogoriva u cestovnom transportu te omogućiti kvalitetno zbrinjavanje otpadnih jestivih ulja bez velikih dodatnih troškova.Various types of bio-components, such as all types of edible oils (sunflower, rape, palm), used edible oils may be used in the fluid catalytic cracking process as part in standard FCC feed. In this work, the used sunflower oil was chosen as a feed added to the standard FCC feedstock in the quantity of 10 v/v % and 20 v/v %. Testing of yield and distribution of products (gas components, LPG, FCC gasoline, light cyclic oil, heavy cyclic oils, and coke) has been performed by the micro-activity test and the obtained results have been compared with the yields and products obtained from the standard feedstock. The equilibrium zeolite catalyst from the commercial FCC unit was used. It was shown how the use of bio-components as the standard FCC feed has been proven to meet the requirements for use of bio-fuels in road transportation, as well as to provide a quality disposal of used edible oils without high added costs