NOVELTY - Making a diesel fuel from a renewable feedstock, comprises: (a) providing a pretreated renewable feedstock (102) containing organic acid groups; (b) neutralizing the acid groups in the pretreated renewable feedstock with ammonia or an amine compound; (c) hydrotreating the neutralized feedstock to form a mixture of n-paraffins; (d) removing the ammonia or amine compounds from the mixture to form a mixture of n-paraffins with a reduced content of ammonia or amine compounds; and (e) isomerizing the mixture to form a mixture of n-paraffins and isoparaffins.    USE - The method is useful for making a diesel fuel from a renewable feedstock.    ADVANTAGE - The method: utilizes the ammonia or amine compounds to reduce or eliminate the impact of corrosion and fouling in the feed system; provides recycling of the ammonia/amine compounds for reuse; and provides the removal of ammonia or amine compound from the product mixture before the isomerization zone so that it does not affect the isomerization catalyst.    DETAILED DESCRIPTION - Making a diesel fuel from a renewable feedstock, comprises: (a) providing a pretreated renewable feedstock (102) containing organic acid groups, where the pretreated renewable feedstock pretreated to remove contaminants; (b) neutralizing the acid groups in the pretreated renewable feedstock with ammonia or an amine compound; (c) hydrotreating the neutralized feedstock to form a mixture of n-paraffins; (d) removing the ammonia or amine compounds from the mixture of n-paraffins to form a mixture of n-paraffins with a reduced content of ammonia or amine compounds; and (e) isomerizing the mixture of n-paraffins with a reduced content of ammonia or amine compounds to form a mixture of n-paraffins and isoparaffins.    DESCRIPTION OF DRAWING(S) - The figure shows a simplified schematic view of making diesel fuel by utilizing ammonia or amine compounds.    Pretreated renewable feedstock (102)    Deoxygenation reaction zone (104)    Isomerization zone (116)    Product recovery zone (120)    Carbon oxide stream (128)