NOVELTY - Forming (M1) a biocomponent-containing diesel boiling range product involves hydrodeoxygenating a feedstock comprising a fresh biocomponent portion ( less than or equal to 50 wt.%) and having an oxygen content of at least 2 wt.% by contacting the feedstock with a treat gas comprising hydrogen (at least 80 mol.%) in the presence of a hydrodeoxygenation catalyst under hydrodeoxygenation conditions to form a hydrodeoxygenated product; and separating the hydrodeoxygenated product into a liquid effluent and a vapor effluent.    USE - For forming a biocomponent-containing diesel boiling range product (claimed) useful in the production of diesel fuel.    ADVANTAGE - The method uses relatively low pressure, and high purity hydrogen source; allows a biocomponent feed to be hydrotreated with a relatively pure hydrogen source to remove the oxygen in the feed; uses the hydrodeoxygenation catalyst comprising a catalyst having an activity i.e. less than or equal to 50% of an activity of a fresh hydrotreating catalyst having hydrodenitrogenation and/or hydrodesulfurization functionality; and is safe and cost-effective.    DETAILED DESCRIPTION - Forming (M1) a biocomponent-containing diesel boiling range product involves hydrodeoxygenating a feedstock comprising a fresh biocomponent portion ( less than or equal to 50 wt.%) and having an oxygen content of at least 2 wt.% by contacting the feedstock with a treat gas comprising hydrogen (at least 80 mol.%) in the presence of a hydrodeoxygenation catalyst under hydrodeoxygenation conditions to form a hydrodeoxygenated product; and separating the hydrodeoxygenated product into a liquid effluent and a vapor effluent, where at least a first portion of the liquid effluent having an oxygen content of less than or equal to 500 weight parts per million (wppm) is recycled to the hydrodeoxygenation step, and at least a second portion of the liquid effluent having an oxygen content of less than or equal to 500 wppm is a diesel boiling range product. The hydrodeoxygenation conditions comprise a total pressure of 80-400 psig. The hydrodeoxygenation catalyst comprises a catalyst having an activity i.e. less than or equal to 50% of an activity of a fresh hydrotreating catalyst having hydrodenitrogenation and/or hydrodesulfurization functionality.