PROCESS FOR PREPARING HEAVY BASE OIL Russian patent published in 2018 - IPC C10G65/04 C10G45/64 C10G65/08 

FIELD: technological processes.

SUBSTANCE: present invention relates to a process for producing a heavy base oil that can be used in lubricating oils for protecting internal combustion engines in motor vehicles. Process includes steps of: (a) providing a hydrocarbonaceous feedstock which contains at least 50 % by weight of hydrocarbons boiling above 460 °C, nitrogen in amount in the range of 800–2,500 ppm, and sulphur in an amount in the range of 1.5–4.0 % wt; (b) hydrotreating the hydrocarbonaceous feedstock with a hydrotreating catalyst in the presence of a hydrogen-containing gas under hydrotreating conditions to obtain a hydrotreated product, which contains nitrogen in an amount in the range of 30–80 ppm and sulphur in an amount in the range of 200–450 ppm; (c) removing at least 50 % of the NH₃ and H₂S, which is present in the hydrotreated product obtained in step (b); (d) catalytically dewaxing at least part of the hydrotreated product as obtained in step (c) with a dewaxing catalyst in the presence of a hydrogen-containing gas under catalytic dewaxing conditions to obtain a dewaxed product, which dewaxing catalyst comprises a group VIII metal hydrogenation component, dealuminated aluminosilicate zeolite crystallites and a low acidity refractory oxide binder material which is essentially free of alumina; (e) hydrofinishing at least part of the dewaxed product obtained in step (d) with a hydrofinishing catalyst in the presence of a hydrogen-containing gas under hydrofinishing conditions to obtain a heavy base oil; and (f) recovering the heavy base oil.

EFFECT: disclosed process allows to obtain a base oil in high yield.

15 cl, 7 tbl, 6 ex