Deep removal of 4,6-dimethyldibenzothiophene from model transportation diesel fuels over reactive adsorbent

Abstract

-This paper presents a new reactive adsorbent used to effectively remove 4,6-dimethyldibenzothiophene (4,6-DMDBT) from model transportation diesel fuels. This reactive adsorbent was composed of formaldehyde, phosphotungstic acid and mesoporous silica gel. The experiment was based on an assumed condensation reaction of 4,6-DMDBT with formaldehyde using phosphotungstic acid as catalyst in pore spaces. The effect of temperature and the amount of formaldehyde and phosphotungstic acid loaded on the substrate were investigated in a batch system. In the breakthrough experiment, three different model diesel fuels containing 1000 mg/kg 4,6-DMDBT were pumped through a fixed-bed reactor packed with reactive adsorbent at constant temperature and atmospheric pressure, respectively. The experimental results showed that sulfur-free model fuel was obtained at 80°C despite the presence of aromatics. The sulfur capacity of regenerated reactive adsorbent was almost totally recovered.

Separation of Sulfur-Containing Compounds From Diesel by Oxidation Followed by Solvent Extraction in a Single Drop Column

“…Furthermore, this process has limited capability for removal of several refractory sulfurcontaining compounds, including heterocyclic sulfurcontaining compounds such as dibenzothiophene and its derivatives. Thus, various new desulfurization technologies, such as electrochemical oxidation (Wang et al, 2007), extraction using ionic liquids and polar solvents (Seeberger and Jess, 2010), oxidative desulfurization (ODS) (Ismagilov et al, 2011), selective adsorption (Wang et al, 2012;Hernández-Maldonado and Yang, 2003), and bio-desulfurization (Soleimani et al, 2007) have been proposed as HDS alternative or complementary methods. The oxidation/ extraction desulfurization process is an attractive method due to its mild operating conditions, no need of hydrogen, and high potential to remove HDS refractory sulfur-containing compounds (Hassan et al, 2013;Ito and Van Veen, 2006;Mjalli et al, 2014).…”