P. P. Dik

A new catalyst for the deep hydrotreatment of vacuum gas oil, a catalytic cracking feedstock

A new CoNiMo/Al2O3 deep vacuum gas oil hydrotreatment catalyst designed for the production of catalytic cracking feedstocks containing 200–500 ppm of sulfur is developed. The method for its preparation includes the following stages: the preparation of a support with specified textural, strength, and granulometric characteristics; the synthesis of bimetallic (Co-Mo and Ni-Mo) complex compounds in solution; and their deposition and drying. The new sample is compared to current domestic and imported industrial analogs according to their physicochemical (texture, morphology, active phase structure) and catalytic characteristics and analyzed. It is shown that the catalyst allows hydrotreatment at temperatures 5–20°C lower and target fraction yields 4–13% higher than all the reference samples. The high activity of the new catalyst is due to the formation of one-layer trimetallic Co(Ni)MoS phase particles at the stage of its sulfidation. The catalyst preparation technique is ready for industrial use (OOO Sintez, Barnaul, 1000 t/yr), and the principal technological regimes of the hydrotreatment of vacuum gas oil on the developed catalyst are determined.

Influence of the conditions of hydrogenation treatment of black oil on the yield and properties of the products obtained

The conversion of black oil in hydrogen (hydroconversion) and nitrogen (pyrolysis) media was studied. The influence of the hydrogen pressure and temperature of the hydrotreating of black oil on the yield and properties of the resulting liquid hydrocarbons was examined. Hydrogen actively participates in the conversion of kerogen (major organic component of black oil), which leads to an increase in the conversion of the organic matter, to an increase in the yield of liquid hydrocarbon products, and to improvement of their quality, compared to pyrolysis. The highest conversion of organic carbon (91.7%) and the maximal yield of liquid hydrocarbons (30.7 wt %) were reached in a hydrogen medium at a pressure of 10.0 MPa and a temperature of 400°C.

Hydrocracking of vacuum gas oil in the presence of catalysts NiMo/Al2O3–amorphous aluminosilicates and NiW/Al2O3–amorphous aluminosilicates

Supported nickel–molybdenum and nickel–tungsten hydrocracking catalysts prepared using a support that consists of 70% Al2O3 and 30% amorphous aluminosilicate were characterized by nitrogen and mercury porosimetry, IR spectroscopy of adsorbed CO, and high-resolution electron microscopy. The catalytic tests in hydrocracking of vacuum gas oil containing 3.39% sulfur showed that the nature of the hydrogenating component (NiMo or NiW) only slightly influences the vacuum gas oil conversion and the diesel fraction yield, but noticeable influences the properties of the diesel fraction obtained. The catalyst NiMo/Al2O3–amorphous aluminosilicates, compared to NiW/Al2O3–amorphous aluminosilicates, ensures lower sulfur content in the diesel fraction obtained, whereas the catalyst NiW/Al2O3–amorphous aluminosilicates allows obtaining a diesel fraction with lower content of polyaromatic compounds.

Silica-alumina based nickel-molybdenum catalysts for vacuum gas oil hydrocracking aimed at a higher diesel fraction yield

Nickel-molybdenum hydrocracking catalysts based on amorphous silica-aluminas (ASAs) with Si/Al = 0.3–1.5 have been prepared using chemicals and methods available for catalyst plants. The acidic properties of the ASA surface have been investigated by IR spectroscopy of adsorbed CO, and it has been demonstrated that the Si/Al ratio has an effect on the concentration and strength of Brønsted and Lewis acid sites in the ASA. The catalysts have been characterized by low-temperature nitrogen adsorption and transmission electron microscopy, and it was found that the Si/Al ratio in the ASA has a considerable effect on the textural properties of the catalysts and only a slight effect on the particle size of the sulfide active component. The catalysts have been tested in vacuum gas oil hydrocracking in a laboratory-scale high-pressure flow reactor under typical industrial hydrocracking conditions. The highest diesel fraction yield (>60 wt % at 400°C) has been obtained with the catalyst based on the Si/Al = 0.9 ASA, which has the strongest Brønsted acid sites. With the catalysts based on the Si/Al = 0.3 and 1.5 ASAs, the diesel fraction yield is much lower. This may be due to the lower concentration and strength of acid sites in these catalysts and their smaller specific surface area. The NiMo catalyst based on Si/Al ≈ 0.9 ASA is recommended for industrial use in refineries aimed at obtaining the maximum possible yield of low-sulfur, high-cetane, diesel fuels.

Influence of Temperature on the Hydrogenation of Oil Shale from the Kashpir Deposit

The effect of the hydrogenation temperature of oil shale from the Kashpir deposit on the yield and the properties of the resulting liquid hydrocarbons and gasoline and diesel fractions separated from them was studied. It was found that synthetic oil can be obtained from high-sulfur oil shale with the use of hydrogenation processing. In this case, it is possible to extract more than 90% of the organic matter of oil shale. Depending on the temperature of this processing, the sulfur content of the synthetic oil varied from 2.8 to 4.2 wt %, and the nitrogen and light fraction contents varied from 1.3 to 1.6 and from 34 to 67 wt %, respectively.

Hydrogenation of Bituminous Sand

The effect of the conditions of bituminous sand hydrogenation on the yields and properties of the resulting liquid hydrocarbons was studied. It was found that, on the hydrogenation of bituminous sand, hydrocarbon products of higher quality can be obtained with a higher yield, as compared with the products of pyrolysis. The conditions affording a maximum yield of synthetic oil or an increased yield of light hydrocarbons were determined.

NiMo/USY-Alumina Catalysts with Different Zeolite Content for Vacuum Gas Oil Hydrocracking Over Stacked Beds

The stacked beds comprising hydrotreating catalyst as the top layer, hydrocracking catalyst based on amorphous silica-alumina as the interlayer and hydrocracking catalyst based on USY zeolite as the bottom layer were tested in hydrocracking of mixed feed containing straight-run VGO, heavy coker gas oil, aromatic extract and petrolatum. It is shown that stacked beds with developed catalysts can be successfully used both in the once-through hydrocracking to provide VGO conversion of 70–80% with middle distillates yields up to 50 wt% and in the first stage operation of two stages hydrocracker to provide 35–65% VGO conversion and produce high-quality middle distillates and feed for the second stage. The commercial partner of this work is Gazprom Neft PJSC (Gazprom Neft Omsk Refinery).

Hydrocracking of Vacuum Gasoil on NiMoW/AAS-Al 2 O 3 Trimetallic Catalysts: Effect of the W : Mo Ratio

The effect of the W: (W + Mo) atomic ratio in NiMoW trimetallic catalysts on their catalytic and physicochemical properties is studied. The catalysts are prepared by impregnating a carrier containing amorphous aluminosilicate (AAS) and aluminium oxide with an aqueous solution containing Ni, Mo, W compounds, and citric acid. They are studied via XRF, TEM, NH3 TPD, and low-temperature nitrogen adsorption and are tested in the hydrocracking of vacuum gasoil (VGO). The average length of a sulfide active component layer shrinks as the amount of Mo increases and the amount of W in the catalyst is reduced. XPS data indicate that the degree of sulfidation of tungsten in NiMoW trimetallic catalysts is lower than in NiW catalyst. Testing of the catalysts in hydrocracking of a straight-line VGO at 390–420°C, 16 MPa, a feedstock hourly space velocity (FHSV) of 0.71 h−1, and a H2: VGO ratio of 1200 L/L shows the activities of hydrodesulfurization, hydrodenitrogenation, hydrogenation, and hydrocracking grow along with the W: (W + Mo) ratio. When the process pressure is high and the amount of sulfur in the NiW feedstock is low, the catalysts have higher activity in the target reactions of VGO hydrocracking than NiMo catalyst.

Hydrocracking of Vacuum Gasoil on NiMo/AAS-Al 2 O 3 Catalysts Prepared from Citric Acid: Effect of the Catalyst Heat Treatment Temperature

Ni-Mo bimetallic catalysts are prepared by impregnating a carrier containing amorphous aluminosilicate (AAS) and aluminum oxide using a solution with Ni, Mo, and citric acid. The temperature of the catalysts ranges from 120 to 550°С. The physicochemical properties of the catalysts are studied via XPS, TEM, and HCNS analysis, and they are tested in hydrocracking of vacuum gasoil. The particles of the sulfide active component (NiMoS phase) are localized predominantly on surfaces of aluminum oxide, and only some are on surfaces of AAS. When the temperature of catalyst calcination is raised, the average number of the layers in particles of the NiMoS phase grows as well, due to the removal of citric acid. This indicates strengthening of the interaction between the sulfide active component and aluminum oxide. The content of Ni-Mo massive sulfide particles also grows along with the temperature of calcination. The morphological characteristics of the sulfide active component affect the activity of the catalysts in hydrodesulfurization and hydrodenitrogenation, but not in hydrocracking. The optimum heat treatment temperature for NiMo/AAS-Al2O3 catalysts prepared with citric acid is 120°C. Recommendations are given for the heat treatment of catalysts under industrial conditions.

Hydroconversion of Oil Shale on Natural Mineral Matrices

The hydroconversion of high-sulfur oil shale in the presence of natural mineral matrices: shale ash, sandstone, and clay has been investigated. It has been shown that mineral matrices containing clays and iron exhibit catalytic activity during the hydroconversion of oil shales. Due to this activity, a significant reduction in the sulfur and nitrogen content and an increase in the amount of light fractions in the resulting synthetic oil are achieved.