Extraction induced by emulsion breaking for determination of Ba, Ca, Mg and Na in crude oil by inductively coupled plasma optical emission spectrometry

Abstract

a b s t r a c tThe selection of the sample preparation method is one of the most critical steps in the determination of metals using atomic spectrometry techniques. The aim of this paper was to propose the use of a novel strategy for crude oil sample preparation, based on the extraction induced by emulsion breaking, prior to the determination of Ba, Ca, Mg and Na by inductively coupled plasma optical emission spectrometry (ICP OES). The emulsions were prepared by mixing the crude oils samples diluted in xylene with 5% m/v Triton X-100 solution in 10% v/v HNO 3 . The emulsion breaking was performed by heating at 80 ± 2°C following by centrifugation to improve the separation, resulting in two distinct phases. The aqueous phase was analysed by ICP OES using inorganic standards solutions for external calibration. Ba, Ca, Mg and Na were totally extracted at a single extraction step. The limits of detection were 0.12, 1.2, 0.14 and 5.8 μg L −1 for Ba, Ca, Mg and Na, respectively. The percentage recoveries ranged from 99 to 104% and the good agreement with the values of the certified reference material (NIST 1634c), when student-t test was applied at 95% confidence limit (p b 0.05), warranted the accuracy of the procedure.

Evaluation of Extraction Induced by Emulsion Breaking for Ni and V Extraction from Off-Shore Brazilian Crude Oils

“…The bottom aqueous phase then is collected and analyzed by spectrometric techniques. EIEB has been successfully applied in the determination of metals in different types of oil samples, such as diesel oil, − biodiesel, , edible oils, − used lubricating oil, , jet fuel, and gasoline. ,, A few papers have already been published regarding the application of EIEB in the analysis of crude oils; − however, none of these papers report the determination of Ni or V in this type of sample.…”

Traditional Calibration Methods in Atomic Spectrometry and New Calibration Strategies for Inductively Coupled Plasma Mass Spectrometry

“…The EC method has been effective in several analytical applications involving elemental determination in different types of the matrices, such as crude oils (Trevelin et al, 2016 ; Sugiyama and Williams-Jones, 2018 ), diesel oil (Nora et al, 2017 ), biodiesel (Barros et al, 2017 ), iron supplements (Barbosa et al, 2015 ), vinegar alcohol (Silva Junior et al, 2015 ), sediment (Leao et al, 2016b ), milk (Oliveira et al, 2017 ), canned foods (Leao et al, 2016a ), seawater, mineral water, tap water, cachaça, human blood (Papai et al, 2017 ), among others. In these applications, acid digestion (Barbosa et al, 2015 ; Leao et al, 2016a ; Sugiyama and Williams-Jones, 2018 ), dry decomposition (Nora et al, 2017 ), extraction procedures (Silva Junior et al, 2015 ; Leao et al, 2016b ; Sánchez et al, 2016 ; Trevelin et al, 2016 ; Barros et al, 2017 ; Papai et al, 2017 ; Zeiner et al, 2018 ), and emulsion formation (Oliveira et al, 2017 ) were used for sample preparation. Table 1 shows a summary and additional details on sample preparation procedures used in combination with EC, as well as with MMC.…”

The interaction of milk sphingomyelin and proteins on stability and microstructure of dairy emulsions

“…Protein and PL contents remaining in the aqueous phase of the emulsion formation were quantified after filtration through polyvinylidene fluoride membrane (0.45 μm; Hyundai Micro Co.). The adsorbed protein (PL) content in the cream layer (mg) was calculated as follows: The protein and PL contents of the sample were analyzed by the bicinchoninic assay (Smith et al, 1985) and the inductively coupled plasma optical emission spectrometry method (Trevelin et al, 2016), respectively. The PL content was estimated by multiplying the quantified phosphorus values in the samples by the PL conversion factor [PL molecular weight (MW)/phosphorus MW].…”