Spectrophotoanalytical Raman-based sensing of sulphur-containing compounds in petroleum products: Could SERS be an efficient detection tool in oil industry?

Petroleum demand continues to increase rapidly because of the dynamic development of the world economy. Therefore, the quality assessment related to petroleum products has become a major concern for developed countries. Due to the diverse chemical compositions of petrochemical products, sensitive and fast detection tools of undesirable contaminants always represent an analytical challenge due to the variation in petroleum contents which also vary due to climatic conditions sources of origin. Since petroleum products' quality control relies on the measurement of physical properties, there is always a huge room for innovation to establish reliable and convenient analytical and quantitative approaches that facilitate the quality assurance ecosystem in the petrochemical industry. Spectrophotoanalysis has gained increasing popularity due to its intrinsic ability in providing details not only in terms of sample compositions but also the chemical structure of target analytes. It could be considered to monitor petrochemical reactions, to improve the petroleum refinery process and to quantify the adulteration in petroleum products. In this project, we plan to develop a surface-enhanced Raman scattering (SERS) based detection approach for the quantification of sulphur-containing compounds, such as thiophene, in petroleum samples. A highly plasmonic nanomaterial SERS substrate will be designed and characterized by different tools, such as scanning electron microscopy (SEM), energy-dispersive X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD). The optimum conditions including laser power, acquisition time, excitation wavelength, the ratio of nanomaterial and analyte mixing, and their immersion time will be explored. The interaction between sulphur analytes and SERS substrates will be investigated with the aid of density functional theory (DFT). The feasibility of the analytical protocol for real sample analysis will be assessed in terms of selectivity, reproducibility, and substrate stability.