2.2.1. Kinematic Viscosity

The existence of maximum and minimum limits for the viscosity of a fuel is required for ensuring the engine works without any risk, and fuel injection system is unaffected [31]. The viscosity measures of mixtures were carried out in an Ostwald-Cannon-Fenske capillary viscometer (Proton Routine Viscometer 33,200, size 150) at 40 ◦C, according to the European standard EN ISO 3104 test method and following the methodology described in previous works [16,17].

#### 2.2.2. Pour Point (PP) and Cloud Point (CP)

Cloud point and pour point are cold flow properties responsible for solidification of fuel at cold operating conditions. At low temperatures, fuel crystallization results in clog to fuel lines and filters, which causes problems to start engine as a consequence of the lack of fuel [32].

CP and PP measurements have been performed following the EN 23015/ASTM D-2500 and ISO 3016/ASTM D97 standards, respectively. The experiments are performed in accordance with the procedure described in previous investigations [16,17]. All results are presented as average values of duplicate determinations and error is calculated as standard deviation.
