Heteropoly acid supported on sodium dodecyl benzene sulfonate modified layered double hydroxides as catalysts for oxidative desulfurization

Abstract

Layered double hydroxides (LDHs) modified with sodium dodecyl benzene sulfonate (SDBS) were successfully prepared and applied as catalysts for oxidative desulfurization (ODS). The characterization of the LDH samples indicated that modification with SDBS improves the hydrophilic and lipophilic properties of the LDHs owing to its amphiphilicity. Compared with pristine MgAl-LDH, the SDBS modified MgAl-LDH-DBS samples exhibited significant differences in morphology, surface area, and pore volume. After immobilizing phosphotungstic acid (HPW), the desulfurization activity showed a significant increase compared with that of the HPW/MgAl-LDH catalyst. Under optimal conditions, the desulfurization rate of the catalyst reached 99.81%. Furthermore, the desulfurization rate was still over 95% after 15 cycles. This excellent catalytic activity and recyclability was attributed to the improvement of the surface area, hydrophilicity, and oleophilicity of the LDHs.