Preparation of bimetal modified HMS molecular sieve and its desulfurization performance mechanism

Abstract

AbstractIn this paper, dodecylamine (DDA) is used as the template, and ethyl orthosilicate (TEOS) is used as the silicon source. The HMS molecular sieve is prepared by in situ synthesis and modified by Cu, Ce, and Cu/Ce. The Cu/Ce‐HMS molecular sieve catalyst was synthesized for the first time. Scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), and Fourier transform infrared spectrometer (FTIR) were used to characterize the synthesized composite molecular sieve. The results showed that the metal was loaded on the HMS intact and did not change the morphology of the HMS. A mixture of n‐hexane and dibenzothiophene (DBT) was used as the model oil, and the oxidation removal of DBT in the model oil was used as a probe reaction to study the photocatalytic oxidative desulfurization performance of the composite catalyst. The results show that the desulfurization rate after modification is Cu/Ce‐HMS molecular sieve > Cu‐HMS molecular sieve > Ce‐HMS. Finally, we explored the reaction mechanism of catalyst desulfurization. The results of ultraviolet diffuse reflectance showed that the modified molecular sieve Cu/Ce‐HMS had a smaller band gap, greater reaction activity, and stronger photocatalytic performance, which is benefit to improve the desulfurization efficiency. We report a simple and effective preparation method of composite molecular sieve catalyst, which provides a certain reference for future desulfurization research.