Study on the Electrochemical Oxidation Desulfurization Behavior of Model Diesel on Anodic Alumina Oxide and Ceria Nanotubes

Abstract

Anodic alumina oxide and ceria (AAO–CeO2) nanotubes have been used as an anode catalyst to remove sulfur from the model diesel composed of 1000 ppm of benzothiophene (BT), 600 ppm of dibenzothiophene (DBT), and 300 ppm of 4,6-dimethyldibenzothiophene (DMDBT). During the desulfurization process, BT can be removed by two main routes, i.e., oxidized to sulfone (BTO2) and sulfates (SO4 2–), while for DBT and DMDBT, the main removal way is only to be oxidized to sulfates. The desulfurization efficiencies of 1000 ppm of BT, 600 ppm of DBT, and 300 ppm of DMDBT as individuals are 98.07, 96.82, and 92.65%, which are much higher than their respective desulfurization efficiency in the model diesel (mixture of BT, DBT, and DMDBT). Density functional theory (DFT) calculations and cyclic voltammetry (CV) are further used to study the electrochemical oxidation desulfurization behavior of the three sulfides, and the results show that there may exist a critical point for the sulfur concentration; when the concentration is lower than the point, the desulfurization efficiency increases with increasing the sulfur concentration, whereas when the concentration is higher than the point, the desulfurization efficiency shows an opposite trend.

Synthesis of Feooh and Feooh@zno by Hydrothermal Method and the Adsorption of S2- In Wastewater

“…Under electrochemical oxidation conditions, the removal efficiency of sulfides reached 95.07%. Du used aluminum oxide and white alkane (AAO+CEO) 2 nanotubes as anode catalysts to remove sulfides present in diesel (Du et al, 2018), achieving a removal rate of over 90%. Although the sulfide removal efficiency of the above-mentioned method is high, the investment and energy consumption are large, and currently, it is not suitable for industrial scale-up.…”

Influence of Water on Noncatalytic Oxidative Desulfurization of High-Sulfur Straight-Run Oil Fractions

“…Most of the ODS processes that continue to be developed and improved over the past 20 years are designed to eliminate the latest of the above shortcomings of HDS (reducing the sulfur content to 10–15 ppm and less in hydrotreated fuels). 15 − 28 These processes, as well as HDS, are relatively complex and require the use of expensive catalysts and oxidants. 15 − 28 …”

“… 15 − 28 These processes, as well as HDS, are relatively complex and require the use of expensive catalysts and oxidants. 15 − 28 …”

Molybdenum anchored on NH2‐modified spherical SiO2: A highly efficient and stable catalyst for oxidative desulfurization of fuel oil

“…It is therefore desirable to find some innovative desulfurization technologies to produce ultra‐clean diesel with low environmental pollution and savings in energy . The oxidative desulfurization (ODS) process is an alternative technology to HDS because it can remove DBT and its derivatives under mild, even ambient, conditions without hydrogen consumption . This process includes two steps: (i) DBT and its derivatives are converted to corresponding sulfoxide or sulfone compounds and (ii) the oxidized materials are subsequently separated through extraction or adsorption …”