Dessulfurização de combustíveis via extração líquido-líquido em microdispositivos

Abstract

Conventional methods for removing sulfur compounds perform poorly especially when treating aromatic compounds. Current studies have directed efforts to investigate deep extractive desulfurization (EDS) using microdevices. Microdevices are units with micrometer-sized channels that enhance mass and heat transfer phenomena. For EDS in microdevices to be viable, it is essential to choose the appropriate extractor solvent used. Among the possibilities, an excellent candidate is polyethylene glycol (PEG). The present work aims to analyze the use of PEG 300 and PEG 400 in the removal of dibenzothiophene. The identification of flow patterns was carried out using digital image colorimetry, making it possible to estimate the specific interfacial area and the volumetric mass transfer coefficient. The experiments followed na experimental logic that allowed extracting insights into deep desulfurization. In addition, the mass transfer phenomena involved and the application of the best experimental conditions in a real diesel sample were evaluated. The results obtained with model fuel were able to achieve 99,36% DBT removal with 1,0 minute residence time, 1:1 volumetric ratio, and three extraction cycles, in microchannels with 0,5 mm in diameter and 1,0 m in length. Furthermore, applying the best experimental conditions to diesel, the total sulfur concentration decreased from 1646 to 312 ppm, resulting in an extractive efficiency of 81,04%.