Elemental Analysis of Asphaltenes Using Simultaneous Laser-Induced Breakdown Spectroscopy (LIBS)–Laser Ablation Inductively Coupled Plasma Optical Emission Spectrometry (LA-ICP-OES)
Laser-induced breakdown spectroscopy (LIBS) and laser ablation inductively coupled plasma optical emission spectrometry (LA-ICP-OES) were used simultaneously for the elemental analysis of asphaltene samples using minimum sample pretreatment in combination with low laser energy to reduce the amount of removed particles and avoid carbon deposits in the ablation cell. Quantitative analyses of S, Ni, and V were accomplished with LA-ICP-OES using external calibration with the C line as internal standard. The aromatic/paraffinic nature of the asphaltenes was also obtained throughout the H/C ratio using LIBS and partial least square regression model. The results showed very good agreement (±10%) between the concentration obtained by LA-ICP-OES and microwave-assisted acid digestion values.