Use of xerogels for the elemental analysis of crude oils by laser ablation inductively coupled plasma high resolution mass spectrometry

Abstract

A novel method for the preparation of crude oil samples based on a xerogel matrix was developed for elemental analysis using laser ablation-double focusing sector field inductively coupled plasma-mass spectrometry. The samples and aqueous solution were successfully encapsulated using zirconium npropoxide. The use of xerogel produces stable and homogeneous pellets, avoids splashing of the sample and allows the use of aqueous inorganic standards to elaborate the calibration curve. Sulfur, nickel and vanadium were selected as test elements and indium was used as the internal standard to correct the variations in the amount of material ablated. The correlation coefficients of the calibration curves for all the elements tested were better than 0.990 except for sulfur. Crude oil results showed no significant statistical differences between the sol-gel results and those obtained with similar studies.

Atomic spectrometry update: review of advances in the analysis of metals, chemicals and materials

“…The use of xerogels for elemental analysis of crude oils using LA-ICP-MS was described by Martinez et al 83 Crude oil (0.5000 g) was dissolved in dichloromethane and then added to zirconium n-propoxide. This mixture was then added to ethanol, water, nitric acid and Tergitol to form the xerogel.…”

Elemental Analysis of Asphaltenes Using Simultaneous Laser-Induced Breakdown Spectroscopy (LIBS)–Laser Ablation Inductively Coupled Plasma Optical Emission Spectrometry (LA-ICP-OES)

“…Some strategies have been reported to eliminate these adverse effects, for example, immobilization of the crude oil using powders formed by fusion or pelletizing, liquid nitrogen pretreatments, impregnated samples in cellulose, silica gel plates, specially designed chambers, the use of xerogels, and thin layer chromatography. 34,45–50…”

The use of sol–gels as solid calibration standards for the analysis of soil samples by laser ablation coupled to inductively coupled plasma mass spectrometry

“…10 Recently, the use of the sol-gel process to create solid calibration standards has shown great promise for using LA to analyze a range of sample types. [11][12][13][14][15] Indeed, the sol-gel process is effective at quickly forming standards that are highly homogeneous and allow for the easy inclusion of an internal standard or the addition of powdered sample. It involves the formation of a colloidal suspension from a metal alkoxide, water, co-solvent and an acid or base catalyst.…”