Modern problems related to the presence of chlorine-organic compounds (COC) in crude oil, its production and processing, and sources of COC in oil are considered. The tasks set by modern regulatory requirements for the content of COC in oil and naphtha and the possibility of solving them using analytical methods of existing standards are considered in particular. It is shown that the existing methods for determining COC in oil are not optimal. There is an urgent need to expand analytical methods, increase their accuracy and informativeness.
An important aspect related to the sources of the appearance of COC in oil is noted, namely, one of which is natural, determining some components of crude oil, and the other source is chlorine-containing oilfield reagents used at various stages of oil production, transportation and preparation, as well as products of their thermal and chemical transformations. It is assumed that the formation of COC can occur as a result of hydrochloric acid treatments, hydrolysis of chloride salts, and the interaction of oil components with hydrochloric acid. It is noted that understanding the sources of COC in oil will minimize the risks during its processing. Special tests performed using chromatography-mass spectrometry evaluated the effect of the dosage and nature of the chemical reagents used on the mass fraction of COC in oil. In particular, it was shown that wax solvents containing organochlorine components in working dosages lead to an increase in the content of COC in oil. An important aspect related to the sources of COC appearance in oil is considered. Understanding this aspect will help to minimize the risks associated with organic chlorides during processing. In addition, it is indicated that analytical methods should be developed or modified to control COC in the oilfield reagents used, research should be conducted on the possible generation of COC in the implementation of well acid treatment technologies, and the influence of oil composition on their quantity should be taken into account.
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