SARA analysis

In this zone, the quantity of extracted oil is generally sufficient to obtain the distribution of the different structural groups (SARA analysis) except for oil A (Fig. 6 to 9) For oil B (Fig. 6), for the first two samples, the amount of extracted products is too low and the analysis is uncertain. It can only be noticed that the asphaltene content is null. On the contrary, just beyond the coke zone (samples III-IV), the asphaltene content respectively reaches 12.9 and 5 4 whereas the asphaltene content of the initial oil is only 0.3. This effect is also observed for oil C (10 versus 6.3%) (Fig. 7), D 24% versus 13.8 ) (Fig. 8), E (24 4 versus 8.1 ) (Fig. 9) For all the oils, the amount of resins+asphaltenes generally remains constant and the amount of saturates increases... 

Figure 9. SARA analysis of extracted oil for Oil E. (Reproduced with permission from ref. 8. Copyright 1984 Institut Fran9ais du Petrole.)...

SARA analysis a method of analysis for saturates, aromatics, resins, and asphaltenes. 

The toluene-soluble products from each reacted kerogen were subjected to SARA analysis (saturates, aromatics, resins, asphaltenes) (22). The B toluene solubles gave almost 91% asphaltenes. The C kerogen toluene solubles were almost 81% asphaltenes. The C toluene solubles were more difficult to handle 14.5% of the material was unrecovered from the chromatographic column. 

Fukuyama and Terai used a lumped model to study the kinetics of hydroprocessing of VR (7 to 10 MPa 700K). A total of seven lumps comprising hydrocarbon groups was determined by SARA analysis, as well as different fractions of products and a residue. The kinetics parameters were used to identify the most active Fe/AC catalyst. The same catalyst was the most resistant to deactivation. 

Conversion (upgrading) of bitumen and heavy oils to distillate products requires reduction of the MW and boiling point of the components of the feedstocks. The chemistry of this transformation to lighter products is extremely complex, partly because the petroleum feedstocks are complicated mixtures of hydrocarbons, consisting of 10 to 10 different molecules. Any structural information regarding the chemical nature of these materials would help to understand the chemistry of the process and, hence, it would be possible to improve process yields and product quality. However, because of the complexity of the mixture, the characterization of entire petroleum feedstocks and products is difficult, if not impossible. One way to simpHfy this molecular variety is to separate the feedstocks and products into different fractions (classes of components) by distillation, solubility/insolubility, and adsorption/desorption techniques. For bitumen and heavy oils, there are a number of methods that have been developed based on solubility and adsorption. The most common standard method used in the petroleum industry for separation of heavy oils into compound classes is SARA (saturates, aromatics, resins, and asphaltenes) analysis. Typical SARA analyses and properties for Athabasca and Cold Lake bitumens, achieved using a modified SARA method, are shown in Table 1. For comparison, SARA analysis of Athabasca bitumen by the standard ASTM method is also shown in this table. The discrepancy in the results between the standard and modified ASTM methods is a result of the aromatics being eluted with a... 

Different laboratories may use different methods for the evaluation of feedstock quality. Method variation makes it difficult to compare the data among laboratories. For example, when comparing the properties of different feedstocks - for instance their SARA analysis - the feedstocks should have been distilled to the same nominal cut point. The data in Table 5 show that... 

In an attempt to correlate the thermal cracking behavior of heavy oils to their properties, Liu et al. studied the thermal cracking of 40 heavy oil fractions obtained by supercritical extraction from six Chinese light crude oils and oils from Oman and Saudi Arabia. The thermal cracking experiments were performed at 410°C, 0.1 MPa N2 for 1 hour. A non-linear regression fit indicated that the thermal cracking of the fractions could be correlated with the H/C, S (wt%), N (wt%) and molecular weight. A similar correlation was obtained with SARA analysis, S, and MW. In this study, the coke yields... 

Tissot, B. P. Welte, D. H. (1978). Petroleum formation and occurrence A New Approach to Oil and Gas Exploration. Editor Springer- Verlog, Berlin, Heidelberg Wang, J. Fan, T. Buckley, J. S. (2002). Evaluating Grude Oils by SARA Analysis. Paper SPE-2002 (75228) Presented at SPE/DOE Improved Oil Recovery Symposium in Tulsa, Oklahoma... 

Fan, T.G., Buckley, J.S., (2002), Rapid and accurate SARA analysis of medium gravity crude oils. Energy Fuels, 16,1571-1575. 

These components can be separated by simple technique known as SARA analysis (Saturated, Aromatic, Resin and Asphaltenes). Some examples of the resin and asphaltenes that can be separated by using SARA analysis of are given in Figure 7a b. The SARA analysis process is shown in Figure 8. Particles such as silica, clay, iron oxides, etc. can be... 

There is no universal agreement about the propane/ n-heptane pair, but the general idea is that resins are soluble in higher molecular weight normal alkanes, but are insoluble in lower molecular weight alkanes. A standard method exists to quantify resins by a completely SARA analysis. Resins can be also defined as the most polar and aromatic species present in... 

T. Fan and J. Buckley (2002) "Rapid and Accurate SARA Analysis of Medium Gravity... 

SARA An abbreviation for saturates, aromatics, resins, and asphaltenes, which are the four solubility classes of hydrocarbon fractions of crude oil. The saturates are generally iso- and cyclo-paraffins whereas aromatics, resins, and asphaltenes form a continuum of molecules with increasing molecular weight, aromaticity, and heteroatom contents. Asphaltenes can also contain metals such as niclml and vanadium. A SARA analysis is a method used forthecharacterizationofheavy oils based onfractionation. 

Fukuyama and Terai [21] Kinetic Model 7 Lumps Laboratory SARA Analysis Yield / SARA Analysis N/A Yes N/A N/A... 

Sepulveda, J.A., BoniUa, J.P., Medina, Y. 2010. Stability prediction for asphaltenes using SARA analysis for pure petroleum. Rev. Ing. Reg.7 103-110. 

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