[PERSON]  
1 Department of Chemical Engineering, University of Western Macedonia, GR-50100 Kozani, Greece;  
[EMAIL_ADDRESS] (I.T.P); [EMAIL_ADDRESS] (C.K. ); [EMAIL_ADDRESS] (C.G.T.) [PERSON]  
1 Department of Chemical Engineering, University of Western Macedonia, GR-50100 Kozani, Greece;  
[EMAIL_ADDRESS] (I.T.P); [EMAIL_ADDRESS] (C.K. ); [EMAIL_ADDRESS] (C.G.T.) [PERSON]  
1 Department of Chemical Engineering, University of Western Macedonia, GR-50100 Kozani, Greece;  
[EMAIL_ADDRESS] (I.T.P); [EMAIL_ADDRESS] (C.K. ); [EMAIL_ADDRESS] (C.G.T.) [PERSON]. [PERSON]  
1 Department of Chemical Engineering, University of Western Macedonia, GR-50100 Kozani, Greece;  
[EMAIL_ADDRESS] (I.T.P); [EMAIL_ADDRESS] (C.K. ); [EMAIL_ADDRESS] (C.G.T.) [PERSON]. [PERSON]  
1 Department of Chemical Engineering, University of Western Macedonia, GR-50100 Kozani, Greece;  
[EMAIL_ADDRESS] (I.T.P); [EMAIL_ADDRESS] (C.K. ); [EMAIL_ADDRESS] (C.G.T.) [PERSON]  
1 Department of Chemical Engineering, University of Western Macedonia, GR-50100 Kozani, Greece;  
[EMAIL_ADDRESS] (I.T.P); [EMAIL_ADDRESS] (C.K. ); [EMAIL_ADDRESS] (C.G.T.) [PERSON]  
1 Department of Chemical Engineering, University of Western Macedonia, GR-50100 Kozani, Greece;  
[EMAIL_ADDRESS] (I.T.P); [EMAIL_ADDRESS] (C.K. ); [EMAIL_ADDRESS] (C.G.T.) [PERSON]  
1 Department of Chemical Engineering, University of Western Macedonia, GR-50100 Kozani, Greece;  
[EMAIL_ADDRESS] (I.T.P); [EMAIL_ADDRESS] (C.K. ); [EMAIL_ADDRESS] (C.G.T.) [PERSON]  
1 Department of Chemical Engineering, University of Western Macedonia, GR-50100 Kozani, Greece;  
[EMAIL_ADDRESS] (I.T.P); [EMAIL_ADDRESS] (C.K. ); [EMAIL_ADDRESS] (C.G.T.) [PERSON]  
1 Department of Chemical Engineering, University of Western Macedonia, GR-50100 Kozani, Greece;  
[EMAIL_ADDRESS] (I.T.P); [EMAIL_ADDRESS] (C.K. ); [EMAIL_ADDRESS] (C.G.T.) [PERSON]  
1 Department of Chemical Engineering, University of Western Macedonia, GR-50100 Kozani, Greece;  
[EMAIL_ADDRESS] (I.T.P); [EMAIL_ADDRESS] (C.K. ); [EMAIL_ADDRESS] (C.G.T.) [PERSON]  
1 Department of Chemical Engineering, University of Western Macedonia, GR-50100 Kozani, Greece;  
[EMAIL_ADDRESS] (I.T.P); [EMAIL_ADDRESS] (C.K. ); [EMAIL_ADDRESS] (C.G.T.) [PERSON]  
1 Department of Chemical Engineering, University of Western Macedonia, GR-50100 Kozani, Greece;  
[EMAIL_ADDRESS] (I.T.P); [EMAIL_ADDRESS] (C.K. ); [EMAIL_ADDRESS] (C.G.T.) [PERSON]  
1 Department of Chemical Engineering, University of Western Macedonia, GR-50100 Kozani, Greece;  
[EMAIL_ADDRESS] (I.T.P); [EMAIL_ADDRESS] (C.K. ); ktsanaktsidis@uowm. The most common fuels today are the products of the distillation of crude oil, i.e., petroleum, petrol, gasoline, kerosene, etc. Biofuels, produced from biomass, are considered renewable fuels, with lower emissions over their entire life cycle than conventional fossil fuels. In particular, they are solid, liquid, or gaseous fuels and are produced directly or indirectly from biomass. The most common biofuels today are biodiesel, bioethanol, and biogas. In particular, biodiesel, as an alternative fuel, has significant importance for diesel engines because it can be blended with diesel in various ratios, without the need for specific adjustments to the engine design [3]. Biodiesel can be produced (i) by feedstock that are usually derived from food crops such as maize (corn), sugarcane, and wheat (first-generation biofuels), (ii) by non-edible raw materials including biomass waste, wheat and corn stalks, wood, energy crops, and animal fats (second-generation biofuels), and (iii) by microalgae as a very good source of lipids (third-generation biofuels) [4]. Biodiesel is produced by the transesterification of lipids with a low-molecular-weight alcohol (methanol) and the use of strong basic homogeneous catalysts such as hydroxides (i.e., NaOH) [5]. The main feedstock is usually vegetable oils, while cooking oils (mainly frying oils) and animal fats are used to a lesser extent [6; 7].