Desulphurisation of dibenzothiophene and 4,6–dimethyl dibenzothiophene via enhanced hydrogenation reaction route using RePd–TiO2/SiO2 aerogel catalysts: kinetic parameters estimation and modelling
Autor: | Prokić-Vidojević Dragana, Glišić Sandra B., Pešić Radojica, Orlović Aleksandar M. |
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Jazyk: | English<br />Serbian |
Rok vydání: | 2022 |
Předmět: | |
Zdroj: | Hemijska Industrija, Vol 76, Iss 3, Pp 135-145 (2022) |
Druh dokumentu: | article |
ISSN: | 0367-598X 2217-7426 |
DOI: | 10.2298/HEMIND220114008P |
Popis: | Re/Pd-TiO2/SiO2 aerogel catalysts were synthesized by using a sol-gel method and supercritical drying in excess solvent and investigated in the reaction of hydrodesulphurisation (HDS) of dibenzothiophene (DBT) and 4,6-dimethyl dibenzothiophene (4,6-DMDBT). Both Re/Pd catalysts, obtained with and without the use of mesitylene in the synthesis step, have shown increased conversions of up to 70 % in the desulphurization of 4,6-DMDBT, when compared to conventional Co/Mo hydroprocessing catalysts. This observation is of importance for conversion of highly refractory 4,6-DMDBT and hydroprocessing to produce ultra-low sulphur diesel fuels, ULSD. In order to quantify the extent of desulphurisation, which proceeds via a hydrogenation route, conversions of DBT and 4,6-DMDBT along with evolution of reaction products characteristic for the direct desulphurisation route and the hydrogenation route were monitored by using a gas chromatography–mass spectrometry (GC-MS) analytical technique. The reaction was performed at 630 K and 6 MPa in a batch catalytic reactor. The experimental results were used in the Hougen-Watson kinetic model describing DBT and 4,6-DMDBT desulphurisation on σ and τ active sites. Kinetic parameters of this complex catalytic kinetics were determined by using a Genetic Algorithm method and minimum deviation function. Values of calculated kinetic parameters and values of the ratio of 3-methylcyclohexyltoluene (MCHT and dimethyl biphenyl (DMBPH) expressed as the MCHT/(MCHT+DMBPH) ratio ranging between 0.66 and 0.94, have confirmed that the hydrogenation route is the dominant route for desulphurisation of 4,6-DMDBT. |
Databáze: | Directory of Open Access Journals |
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