Determination of Saturate, Aromatic, Resin, and Asphaltenic (SARA) Components in Crude Oils by Means of Infrared and Near-Infrared Spectroscopy

Abstract

Eighteen crude oils and condensates have been investigated by means of infrared (IR) and near-infrared spectroscopy (NIR) and high-performance liquid chromatography (HPLC). By means of HPLC the samples have been separated into four chemical group classes, namely saturates, aromatics, resins, and asphaltenes, the so-called SARA fractions. Using multivariate analysis techniques such as principal component analysis (PCA) and partial least-squares analysis (PLS), the predictive ability of the spectroscopic techniques with regard to the SARA components have been explored. The results show that the SARA distribution of crude oils and related materials can be determined both from infrared and near-infrared spectroscopy. The uncertainties in the prediction models based on IR spectroscopy have been found to be 2.5, 2.2, 1.4, and 1.3 wt % for the saturate, aromatic, resin, and asphaltene fraction, respectively. For NIR the equivalent uncertainties are 2.8, 2.4, 1.4, and 1.0 wt %. These values are in the same range as the reported uncertainty in the direct determination by HPLC. Spectroscopic determination of SARA values, especially using NIR, offers the possibility of rapid SARA determinations of these values. The determinations could be done at high pressure and temperature.

Towards enhancing sustainable reuse of pre-treated drill cuttings for construction purposes by near-infrared analysis: A review

“…have all been determined by vis-NIR spectroscopy. The vis-NIR spectra of petroleum derivatives is known to originate mostly from overtones or combinations of C-H stretch vibration modes of CH 2 and CH 3 , or aromatic C-H (ArCH) functional groups (Aske et al, 2001). As shown in Figure 8, these functional groups have absorption features around 712,750,850,900,1097,1137,1162,1227,1417,1675, and 1712 nm in the NIR region.…”

A Rapid Method of Crude Oil Analysis Using FT-IR Spectroscopy

“…This, itself, has been driven by the need in the techniques for increased sensitivity, specificity and sophistication on one hand (Hunt et al, 2002) and the need for simplicity and rapid response on the other (Larter and Aplin, 1995), since it is common to have up to 500 core extracts waiting to be screened (Larter and Aplin, 1995) Prior to the advent of combined gas chromatography/mass spectroscopy (GCMS), sample characterization (Crude oil), had been carried out using liquid chromatography (LC), thin layer chromatography (TLC) and gas chromatography (GC) (Larter and Aplin, 1995). However, these techniques are lengthy, tediousand laborious, as well as expensive to run on a routine basis (Aske, 2001). It is therefore practically impossible to contemplate rapid analysis of an organic mixture having many components (i.e.…”

“…High pressure liquid chromatography has since been developed to reduce these difficulties (Aske, 2001).…”

Calculation Method to Determine the Group Composition of Vacuum Distillate with High Content of Saturated Hydrocarbons

“…and heteroatoms (S, O, N, F) [1,2]. Hydrocarbon components of heavy petroleum fractions are divided into the three main types: paraffinic, aromatic and naphthenic structures.…”