THE EFFECT OF COLD SOAK FILTRATION OF B100 ON SUBSEQUENT COLD FLOW IMPROVER RESPONSE IN B100/ULSD FUEL BLENDS

摘要

Four current generation cold flow improvers were evaluated at 500 ppm(wt) in three B20 diesel fuel blends. The B20 diesel fuel blends were made by blending a biodiesel-free summer grade ULSD and an ASTM D6751-compliant B100 derived from used cooking oil. The first B20 was made using the B100 as received. The second B20 was made using the B100 after processing by a cold soak filtration process as described in ASTM D6751-10 annex, now ASTM D7501. The third B20 was made using another portion of the B100 similarly cold soaked but filtered cold after being removed from the cold soak chamber. The resulting three B20 fuels were evaluated with no cold flow improver additive as well as with 500 ppm(wt) of each of the four selected cold flow improver additives. Cold flow tests included Cloud Point, Pour Point, and Cold Filter Plugging Point. Also, FAME Speciation by EN 14103 was performed on two of the B100's. Results indicated that both B100 cold soak filtration procedures failed to provide any significant improvement in the cold flow properties of the additive-free B20 blends as well as the additized B20 blends. FAME speciation showed that even after the cold soak/cold filtration (with a visibly significant portion of the original B100 still solid and not part of the filtrate) the composition of the filtered B100 had not significantly changed relative to the original B100. These results suggest that efforts to improve the cold flow properties of B100 by ordinary fractional crystallization are likely to not be successful beyond imparting compliance with the D7501 requirement of D6751.