NOVELTY - The process involves subjecting a feedstock (1) including material of biological origin to purification treatment to obtain a purified feedstock (4). The purified feedstock is subjected to hydroprocessing in presence of hydro-de-oxygenation catalyst, where a hydro-de-waxing catalyst and a hydro-de-aromatization catalyst obtain a hydroprocessing product (7). Purification treatment i.e. evaporative treatment, is carried out in an evaporation unit (20) including three or four evaporators. The purified feedstock is subjected to pretreatment carried out with guard beds.    USE - Process for converting feedstock with biological origin materials to hydrocarbons for use as liquid fuel or fuel components. Uses include but are not limited to spent motor oil, industrial lubricants, paraffin waxes, coal gasification liquid, biomass, natural gas, depolymerization liquid and thermal or chemical waste plastic e.g. polypropylene, high density polyethylene and low density polyethylene.    ADVANTAGE - The process enables converting the feedstock with material of biological origin into the hydrocarbons having improved cetane rating for use as liquid fuels and fuel components in an efficient and cost-effective manner.    DETAILED DESCRIPTION - The process enables defining a hydrodearomatizing catalyst on a support selected from an oxide support, a carbon support, a charcoal support and a zeolite support. The process enables defining a hydrodewaxing catalyst on a support made of zeolite. The purification treatment defines purification step selected from a group consisting of filtration step, degumming step, bleaching step, solvent extraction step, hydrolysis step, ion-exchange resin treatment step, mild acid wash step and evaporative treatment step. The guard beds are selected from active guard beds and inactive guard beds. The process enables defining a hydrodearomatizing catalyst on the support made of a material selected from a group consisting of metal sulfide, yttrium-aluminum oxide, sulfidized cobalt-molybdenum, nickel-molybdenum on alumina/alumina-silica and platinum-palladium on aluminum oxide-boron oxide.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic block diagram illustrating a process for converting feedstock with biological origin materials to hydrocarbons in which the feedstock is subjected to purification followed by pretreatment with guard bed/guard beds, hydrodeoxygenation/hydrodewaxing/hydrodearomatizing treatment in a hydroprocessing reactor system, separating hydrogen for recycling and obtaining a liquid product, which is subjected to fractionation.    Feedstock (1)    Purified feedstock (4)    Hydroprocessing products (7, 8)    Evaporation unit (20)    Hydroprocessing reactor system (30)    Separator (40)