Molybdenum boron based catalysts loaded on MnO alumina support for hydrodesulfurization of dibenzothiophene

Abstract

The influence of boron on the activity of a hydrodesulfurization, HDS, catalyst was evaluated for the cleaner production of fuel. Thus, mixed oxides of γ-alumina and manganese oxide MnO were synthesized as a support and then loaded with molybdenum -copper, Mo-Cu, which work as an active phase and promoter. Different contents of boron were added to the synthesized catalysts to form AlMnO/MoCuB 0% (MAB 0), AlMnO/MoCuB 1% (MAB 1), AlMnO/MoCuB 2% (MAB 2) and AlMnO/MoCuB 5% (MAB 5). The textural properties of the materials were improved after the addition of boron from 164 m2/g of the control catalyst to 225, 258 and 265 m2/g for MAB (1), MAB (2) and MAB (5). X-ray diffraction (XRD) and Fourier transform infrared (FTIR) were utilized for structural characterization. X-ray photoelectron spectroscopy (XPS) was used to attain data on the chemical states and binding energies of the catalysts. A thermogravimetric analyzer (TGA) was utilized to assess the thermal stability of the catalysts. The catalytic activity was tested in a batch reactor system for the HDS of dibenzothiophene (DBT), under the following reaction parameters: T of 300 °C, hydrogen pressure of 55 bar and 6 h reaction time. After boron addition, it became 98% (MAB 5) compared to 87% of the MAB0 control catalyst and that clarified the role of boron in enhancing the catalyst performance.