Better sulfide catalysts through optimized active phase-support interaction
In this project, improved hydrotreating catalysts were synthesised by varying the active phase-support interaction through calcination and the choice of different carriers. The active phase consisted basically of Mo or W with Ni, Co, Cr, Fe as second components and phosphorus as a promoter. For the preparation of the catalysts, a new type of carrier, filamentary carbon supported by alumina, was synthesised and a new type of active phase precursor, acetylacetonate, was used in varying the solvent (water, ethanol, toluene). The consequences of these variations were investigated from a physico- chemical point of view in relation to the actual performance of the newly prepared catalysts in the hydrodesulphurisation of thiophene. Mössbauer emission and absorption spectroscopy, X-ray photoelectron spectroscopy and extended X-ra7y 7photoelectron spectroscopy were used, resulting in a detailed model of7 the so-called "CoMoS" phase. Chemical fingerprinting techniques - TPR (temperature programmed reduction) and TPS (temperature programmed sulphidation) - were also applied extensively. The sulphided catalysts contain different sulphur species and the existence of a very reactive sulphur species, "excess sulphur", was correlated with the hydrodesulphurisation activity. A model was developed to describe the coke deposition on hydrotreating catalysts under commercial reaction conditions.
Bibliographic Reference: EUR 13219 EN (1991) 253 pp., MF, ECU 12
Record Number: 199110024 / Last updated on: 1994-12-02
Original language: en
Available languages: en