A variety of fuel additives for diesel and biodiesel are commercially available to improve the cold flow properties. Dunn et al. (1996) studied the effects of 12 cold flow additives for petroleum diesel on the cold flow behavior of biodiesel. They concluded that the additives significantly improved the PP of diesel/biodiesel blends but did not affect the CP greatly. Many additives contain some proprietary components such as copolymers of ethylene, vinyl acetate, or other olefin-ester copolymers. Because of these proprietary compounds, the impact of cold flow additives on biodiesel from different types of feedstock such as canola, mustard, and used vegetable oil needs to be determined experimentally.
University of Idaho scientists studied the effects of four commercially available cold flow additives on biodiesel made from soy oil, mustard oil, and used vegetable oil. Of these three types of biodiesel, mustard biodiesel responded best to the additives. Still, the researchers found that the additives did not work as well for biodiesel as for petro-diesel. The average reduction in CP and PP for 100% mustard biodiesel was 0.3°C and 7.2°C, respectively. However, the additives reduced the PP of petroleum diesel by at least 16°C, to below -36°C in all cases studied
(Shrestha et al., 2008).