A new approach to deep desulfurization of gasoline by electrochemically catalytic oxidation and extraction

In order to further reduce the sulfur content in gasoline, a new desulfurization process for gasoline was obtained by means of electrochemically catalytic oxidation and extraction with an electrochemical fluidized-bed reactor. The particle group anode was activated carbon-supported lead dioxide (β-PbO₂/C). The electrolyte was aqueous NaOH solution, and copper pillar was cathode in the electrochemical reactions. The β-PbO₂/C particle group anodes can remarkably accelerate the electrochemical reaction rate and promote the electrochemical catalysis performance for the electrochemical desulfurization reaction. Also, gasoline desulfurization rule was investigated in an alkali solution. The experimental results indicated that the optimal desulfurization conditions were as follows: the cell voltage, the pH value of the electrolyte, feed volume flow rate and the β-PbO₂ percentage by weight were 3.2 V, pH value 13.1, 300 ml min^{− 1} and 5.0 wt.%, respectively. Under these conditions the concentration of sulfur in gasoline was reduced from 310 to 40 μg g^{− 1}, and the main properties of the product were not significantly affected. Based on these experimental results, a mechanism of indirect electrochemical oxidation was proposed.