The initial distillation of crude oil is used to remove lighter petroleum fractions such as petrol and naphtha, leaving behind a residue composed of feedstocks like fuel oil, coke, grease, and asphalt. This residue is processed through a vacuum distillation unit to separate feedstocks for lubricant oil production. Lubricant oil production involves hydrotreating, deasphalting, and dewaxing processes, which remove components such as polycyclic aromatic hydrocarbons, asphalt-like compounds, and straight-chain alkanes. Mineral oil production requires extensive refining, resulting in relatively high energy demand compared to other refinery products.