Determination of Organic Chloride Content in the Specialty Oilfield Chemicals Used in the Crude Oil Extraction, Transportation and Refining by X-ray Fluorescence Spectrometry

The organic chloride content in crude oil being among the most crucial quality characteristics of the crude is strictly controlled. The presence of organic chlorides in crude oil greatly endangers the oil refineries since it causes a severe equipment corrosion. Specialty oilfield chemicals, which are widely used in the crude oil extraction, transportation, refining and storage, could be a source of the crude oil contamination with organic chlorides. As a consequence, the organic chloride content determination in the chemicals is required. It was demonstrated that the organic chloride content in the specialty oilfield chemicals can be determined by X-ray fluorescence spectrometry (XRF) using an appropriate specimen preparation procedure. Two specimen preparation procedures, i.e. the solvent extraction and the distillation of a specimen mixed with the crude oil or its model, were tested. It was established that an organic chloride content can be successfully determined in a broad range of the specialty oilfield chemicals by the XRF technique when applying these specimen preparation procedures. The investigation of four types of the specialty oilfield chemicals confirmed that the specimen preparation procedure, involving a solvent extraction of organic chlorides from the chemicals into isooctane, is more comprehensive than the distillation procedure since it is free from the limitations associated with the use of high temperatures.