Study on the performance mechanism of methacrylate pour point depressant in soybean biodiesel blends

Abstract

The cold flow properties of soybean biodiesel blends with 0# diesel and methacrylate pour point depressant (10-320) were investigated in this study. Results showed that all of the fuel properties of the prepared biodiesel satisfied the qualification for ASTM D6751. Along with the increasing amount of pour point depressant (PPD) addition, the cold filter plugging point (CFPP) of the system was reduced. The addition of a constant amount of pour point depressant resulted in minimal values of CFPP in the system, as the volume ratio of biodiesel varied from 0% to 100%. The addition of 1% of 10-320 PPD in B60 produced a CFPP of −10 °C, which was the most significant reduction in biodiesel blends. Other fuel properties of B60 were in accordance with ASTM D6751 and EN 14214. Differential scanning calorimeter, low-temperature X-ray diffraction, and polarizing optical microscope were used to investigate the performance mechanism. Results showed that the crystallization rate of B60 was the slowest; the crystals were small, spherical particles; the particle size <20 μm; and the energy of the solid–liquid transition was the lowest. The crystal content in B60 was the least, the ratio of the peak area of the orthorhombic and monoclinic crystals was 0.086. The orthorhombic crystals were relatively less than the monoclinic crystals. As monoclinic crystals could easily pass through the filter, the CFPP of B60 was the lowest.