Hydrotreating of oil fractions

Recycling the CoMo/Al2O3 catalyst for effectively hydro-upgrading shale oil with high sulfur content and viscosity

“…H 2 pressure is known to improve the HDS reaction performance by increasing the supply of H 2 in the liquid phase, thereby increasing hydroconversion and suppressing coke formation. 26 As for the slight increase in gas yield as observed in Fig. 3b, it can be explained that not every molecule of hydrogen partakes in the HDS reaction; therefore, as the H 2 pressure increases, so does the unreacted gas, leading to the rise of the gas products.…”

“…This could be because a too high reaction temperature for HDS reaction could result in loss of selectivity and higher catalyst deactivation. 26 Another reason could be that, since reactive sulfur compounds, such as thiophenes, benzothiophenes (BTs), are the most abundant sulfur compounds in shale oil and are easily converted at moderate temperatures from 340 to 380 C, hence the rapid sulfur removal. For example, the hydrogenation activity of thiophenes is three times higher than that of dibenzothiophenes, 27 which justify the rapid HDS efficiency observed at the range of 340-380 C. Thus, the small HDS efficiency change from 400-420 C signies the conversion of the refractive sulfur compounds, such as DBTs and 4,6-DMDBTs, which are difficult to be removed.…”

Hydrocracking: A Perspective towards Digitalization

“…Due to lower concern of pressure drop, the catalyst particles of this process are typically smaller, around 0.8 mm [21], which results in a higher conversion of up to 90%. The most significant disadvantage of EBRs in HC is the higher amount of catalyst need [27]. Al-Dalama and Stanislaus studied the deactivation pattern of FBR and EBR catalysts and gave an insight into excess catalyst use of EBRs [28].…”

Stochastic Modeling and Simulation Approach for Industrial Fixed-Bed Hydrocrackers

“…5 To simulate adiabatic reactor operation, it is also common to use a lumped heat of reaction in the heat balance equation. 6 This term is essentially a model parameter obtained by regression of plant data 7 and is considered an approximate average of the net heat release of all reactions. A few examples of adiabatic hydrocracker simulations using this approach are available in the literature.…”

“…Because of the complexity of hydrocracking chemistry and feedstock composition, process models often rely on simplified reaction schemes formulated in terms of broad chemical lumps defined by bulk property measurements . To simulate adiabatic reactor operation, it is also common to use a lumped heat of reaction in the heat balance equation . This term is essentially a model parameter obtained by regression of plant data and is considered an approximate average of the net heat release of all reactions.…”