Co-Processing Of Rapeseed Oil - Straight Run Gas Oil Mixture: Comparative Study Of Sulfide Como/Al2o3-Sapo-11 And Nimo/Al2o3-Sapo-11 Catalysts

Co-processing of mixture, containing 30 wt.% of rapeseed oil (RSO) in straight run gas oil (SRGO), was studied over stacked bed sulfide catalytic system containing Mo/Al2O3 as a first layer and CoMo/Al2O3-SAPO-11 or NiMo/Al2O3-SAPO-11 catalyst as the second one. The experiments were performed in a trickle bed reactor at 350-380 degrees C, 4.0-7.0 MPa, 1.5 h(-1) and 1000 Nm(3)/m(3). The hydrodeoxygenation (HDO) of RSO is proceeding over Mo/Al2O3 catalyst mostly through direct HDO route (selectivity > 93 %). The proposed combination of catalysts minimizes the formation of carbon monoxide, that is known as an inhibitor of hydrotreating reactions and can affect the hydroisomerisation/hydrocraking of alkanes over CoMo/Al2O3-SAPO-11 and NiMo/Al2O3- SAPO-11 catalysts. The effects of temperature and pressure on the behavior of Mo/Al2O3-CoMo/Al2O3-SAPO-11 and Mo/Al2O3-NiMo/Al2O3-SAPO-11 systems were studied and the difference in the quality of products were discussed with the emphasis on the cold flow properties. The cloud point of products, obtained in the co processing of RSO-SRGO mixture over Mo/Al2O3-CoMo/Al(2)O3-SAP and Mo/Al2O3-NiMo/Al2O3-SAP catalytic systems was decreased to-8 and-13 degrees C respectively with the temperature increase from 350 to 380 degrees C. In addition, the hydrogenated products produced over NiMo/Al2O3-SAP were characterized by lower final boiling point values and aromatic content in comparison with that produced over CoMo/Al2O3-SAP catalyst. Unexpectedly, the opposite effect of pressure was observed on the cloud point and the conversion of long chain alkanes, which were produced in hydrodeoxygenation of RSO.