Sonochemical and impregnated Co-W/ɣ-Al₂O₃ catalysts : performances and kinetic studies on hydrotreatment of light gas oil

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Date
2007-01-30Author
Vishwakarma, Santosh Kumar
Type
ThesisDegree Level
MastersMetadata
Show full item recordAbstract
ɣ-A₂O₃ supported Co-W based catalysts with varying Co (1 - 3 wt %) and W (7 - 13 wt %) loadings were prepared using impregnation and sonochemical methods. All prepared catalysts were characterized with elemental analysis, BET analysis, X-ray diffraction (XRD), NH₃ temperature programmed desorption (TPD), temperature programmed reduction (TPR) and thermogravimetry analysis (TGA). The performances of all the synthesized catalysts were tested at a pressure of 8.9 MPa, LHSV of 2 h⁻¹ and temperatures of 340, 350 and 360°C in a laboratory trickle bed microreactor for hydrodesulphurization (HDS) and hydrodenitrogenation (HDN) of light gas oil (LGO) derived from Athabasca bitumen. The performance tests with impregnated catalysts indicated a maximum in activity for HDS and HDN reactions (sulfur and nitrogen conversions at 93.0 and 57.1 % at 360°C) for Co(3 wt %)-W(10 wt %)/ɣ-Al₂O₃ whereas the performance tests with sonochemically prepared catalysts showed a maximum in activity (sulfur and nitrogen conversions at 87.9 and 42.5 % at 360 °C) for Co(3 wt %)-W(11.5 wt %)/ɣ-Al₂O₃. These two catalysts were selected for detail performance, optimization and kinetic studies. The effects of reaction temperature (340 - 380 °C), pressure (7.6 - 10.3 MPa), liquid hourly space velocity (1.5 - 2.0 h⁻¹) and hydrogen gas/gas oil ratio (400 - 800 mL/mL) were examined on HDS and HDN of LGO with these catalysts. The reaction kinetics for HDS was best fitted with a Power Law model whereas same for HDN was found to be best represented by a Langmuir-Hinshelwood model with a reasonable accuracy
Degree
Master of Science (M.Sc.)Department
Chemical EngineeringProgram
Chemical EngineeringSupervisor
Dalai, Ajay K.Copyright Date
January 2007Subject
Co-W/ɣ-Al₂O₃
Light Gas Oil
Hydrotreatment
Sonochemical