Diesel Hydrodesulfurization and its Impact on the Fuel Market in Ecuador: A Review

Abstract

This article examines the hydrodesulfurization process used to produce diesel with low sulfur content in Ecuador. The analysis covers the level of processing in the country, the quality of domestic diesel compared to other nations, and the technical and economic requirements of the process. It also explores the need to modify or upgrade catalysts to achieve deep hydrodesulfurization.. Unfortunately, the review found that sulfur content in Ecuadorian deposits is very high, with 3.53 MMkg produced in 2018. Despite improvements in the country’s refineries, diesel sulfur content has only been reduced to 110 ppm.. Ecuador regulates sulfur emissions through the Ecuadorian standard NTE INEN-1489 (2012). This norm classifies the fuel into three types, diesel #1 (3000 ppm), diesel #2 (7000 ppm), and premium diesel (500 ppm), following the use of diesel both in the industrial and transportation sectors. However, Ecuador seeks to adjust to countries with stricter regulations, such as the European Union. The standard that regulates sulfur emissions in this community is Euro VI, which limits the concentration to 10 ppm. One of the challenges in achieving international standards in the hydrodesulfurization units of the Ecuadorian refineries is to modify or improve the catalytic systems. Trimetallic catalysts, both supported and unsupported, can help overcome this challenge by decomposing the refractory molecules (e.g., dibenzothiophene and 4,6-dimethyldibenzothiophene) found in deep hydrodesulfurization. These catalysts can handle molecules that commonly used catalysts such as CoMo or MoW cannot. Therefore, proposals such as using trimetallic catalysts to achieve deep hydrodesulfurization levels are techno-economic options for Ecuador. Keywords: diesel, sulfur, Ecuador, hydrodesulfurization, refineries, catalyst.