Crude quality has been a hot topic lately. With increased water activity along the Gulf Coast, a high quality barrel is desired now more than ever. Permian WTI exports have continued to increase as production increases and refining capacity remains relatively stagnant (outside of ExxonMobil’s recent Beaumont expansion). This has led to more scrutiny of Permian quality and more surface concerns, both from pockets of low-quality WTI produced at the wellhead and from the mix of market participants, as many midstream suppliers and traders they have become efficient at capturing arbitrage opportunities. . Recent concerns about the quality of WTI have focused primarily on the content of metals, hydrogen sulfide (H2S) and mercaptans, while nitrogen has become a major problem in the natural gas market. In today’s RBN blog, we look at the issue of mercaptans in WTI.
Let’s start with the basics. Mercaptans are natural contaminants of crude oil and natural gas, also called thiols, mercaptans are sulfur-bound organic compounds. Their presence can vary from a few parts per million (ppm) to several thousand ppm. Although mercaptans are undesirable in crude oil (for reasons we will discuss in a moment), they have some commercial applications. Some non-corrosive mercaptans are injected into natural gas to provide a distinctive “rotten egg” odor to help detect leaks, and another type of mercaptan is used to produce methionine, which serves as an intermediate in pesticide production, fungicides and animals. feed additives.
Mercaptans are problematic in crude oil because they can be corrosive, which can have negative implications for pipelines and refining equipment. For refineries, high mercaptan content presents a significant risk of loss of catalyst activity, and denying the catalyst reduces overall fuel quality and decreases yield. Additionally, the presence of mercaptans can decrease catalyst life, creating downtime and unplanned costs for the refiner. Finally, the tendency of mercaptans to create very pungent odors during refining is also a problem, especially for refineries near residential and commercial areas.
