Catalytic hydroprocessing is an effective technology with various applications in the petrochemical industry that are lately expanding in the area of biofuels production. The selection of a hydroprocessing catalyst is a critical step defining the hydrotreating products' yields and their corresponding quality as well as the expected run-length of the process. This work involves the process of selecting a suitable hydroprocessing catalyst for the conversion of waste cooking oil into biofuels. In particular three commercial catalysts are evaluated: a hydrotreating catalyst, a mild-hydrocracking catalyst and a severe hydrocracking catalyst. The catalyst effectiveness was assessed over a temperature range suggested by the catalyst manufacturers, covering a temperature range of 330-390 degrees C, under constant LHSV (1 h(-1)) and a range of pressure 8.27-13.79 MPa. Several parameters were considered for evaluating the effect of temperature including product yields, conversion, selectivity (diesel and gasoline), heteroatom removal (sulfur, nitrogen and oxygen) and saturation of double bonds. (C) 2011 Elsevier Ltd. All rights reserved.