Biodiesel and Renewable Diesel Blends Oxidation by Diesel Oxidation Catalyst

Soy-based mono-alkyl esters of long chain fatty acids is the most common biodiesel fuel used in the United States. Other renewable fuels such as renewable diesel (RDE) is also popular, especially in the state of California. All the renewable and alternative fuels are being evaluated for their performance and performance transparency with ultra-low sulfur diesel (ULSD) to be used a substitute to ULSD. Previous research with biodiesel, showed an elevated lightoff temperature on diesel oxidation catalyst (DOC) and worse DOC efficacy in oxidizing fuel blends with fuel blends with more than 20% biodiesel. A similar study was conducted with RDE to gage the performance of the fuel blends of B100 and RDE. The same DOC used in past study was used to evaluate fuel blends of 100% RDE to 40% RDE (B60R40) in decrements of 10%. The performance of the DOC was evaluated on steady-state performance cycle and transient lightoff curve. Similar to the results in past study, the performance of the DOC is significantly affected by even a small quantity of B100. At low flow rates 50% (B50R50) and higher B100 blends have a poor performance. At mid and high flow rate, blends of 20% (B20R90) and higher have progressively worse performance. The lightoff temperature of the fuel blends progressively increased with an increase in B100 fraction in the fuel blends. This is thought to be because of the higher boiling point of the B100.