Comparison of the Accelerated and Spontaneous Deactivation of the HDS Catalyst

Abstract

Owing to the increased use of secondary materials for diesel production, refineries must confront bad quality parameters. Therefore, catalysts with certain capabilities (to remove heteroatoms and improve quality parameters at low hydrogen consumption) and their lifetimes are required. An important parameter that influences the quality of the products and the economy of the unit is the activity of the catalyst. Prior to industrial use, the catalyst is typically tested in a pilot unit. This is necessary to obtain a considerable amount of data on the lifetime of the catalyst in the shortest feasible time. Here, deactivation steps were used to test the catalyst. Two experiments were performed to evaluate the effect of two types of accelerated deactivations on the catalyst activity and product properties. The first type of deactivation proceeded for 6 h and comprised a tripling of the amount of incoming feedstock, and the second type proceeded for 18 h without an increase in the amount of feedstock. For both cases, the pressure and hydrogen flow were minimised. Both types of accelerated deactivations had similar effects on the quality of the final products and catalyst. The only difference was in the duration of catalyst recovery after deactivation. The results were compared with those of a test in which the spontaneous deactivation of the catalyst was studied.

Long-Term Coprocessing of Used Cooking Oils with Refinery Petroleum Fractions: A Comprehensive Study of Catalyst Activity and Biofuel Production Effects

“…Analytical data obtained from the study of the spent catalyst indicate that the processed raw material with different additions of UCO to the standard raw material F–U0 did not have a significant effect on the catalyst. The state of the catalyst after the experiment corresponds to spontaneous deactivation even in view of the duration of the entire experimental test of 1844 h TOS when it was necessary to increase the temperature by only 11 °C to achieve the required sulfur content in the product (10 mg·kg –1 ) …”

“…The state of the catalyst after the experiment corresponds to spontaneous deactivation even in view of the duration of the entire experimental test of 1844 h TOS when it was necessary to increase the temperature by only 11 °C to achieve the required sulfur content in the product (10 mg•kg −1 ). 77 A scanning electron microscope (SEM) analysis was used to look at the distribution of carbon deposits on the surface of the spent catalyst as well as selected elements, including sulfur, aluminum, nickel, and molybdenum (Supporting Information Figure S8). 77 Subsequently, pictures were taken with a Raman microscope in order to evaluate the morphology and homogeneity of the surface of the spent catalyst after the end of the pilot testing (Supporting Information, Figure S9).…”

“…77 A scanning electron microscope (SEM) analysis was used to look at the distribution of carbon deposits on the surface of the spent catalyst as well as selected elements, including sulfur, aluminum, nickel, and molybdenum (Supporting Information Figure S8). 77 Subsequently, pictures were taken with a Raman microscope in order to evaluate the morphology and homogeneity of the surface of the spent catalyst after the end of the pilot testing (Supporting Information, Figure S9). From the results obtained by Raman microscopy, the surface of the catalyst can be evaluated as homogeneous.…”

Pyrolysis Oils from Used Tires and Plastic Waste: A Comparison of a Co-Processing with Atmospheric Gas Oil

“…The mentioned reversible inhibition is also evidenced by the fact that after returning the standard raw material (SRGO) processing, the reaction temperature could be reduced again to a comparable level as before the co-processing. The detected difference in the WABT between step I and III can be attributed to the effect of the spontaneous deactivation of the HDS catalytic system [33]. When processing the raw material by adding the POP, the temperature difference was 0.5 • C, and did not have to be adjusted.…”