Re-Additization of Commercial Biodiesel Blends During Long-Term Storage

Earl Christensen, Robert McCormick, Teresa Alleman

Research output: Contribution to journalArticlepeer-review

9 Scopus Citations


Commercial biodiesel blends were aged at 43 °C while monitoring stability. The oxidation stability—or oxidation reserve expressed as Rancimat induction period (IP)—gradually decreased from its initial value. At a predetermined IP threshold, an antioxidant was used to restore IP to the ASTM D7467 specification minimum of 6 h, referred to as re-additization. At lower IP values, the amount of antioxidant required increased significantly, and the effectiveness tended to be reduced. Once IP fell to essentially zero, the acid content increased to above the allowable limit and insoluble material was also detected. Storage life was increased relative to the as-received fuels as evidenced by longer time to produce acids. Experience in the field may vary based on storage conditions; however, these results indicate re-additization can significantly increase storage life of biodiesel blends when used with regular monitoring of IP and acid number. An assessment of the storage stability of the as-received fuels showed that the initial IP did not predict storage behavior, although fuels above the specification minimum remained stable for >12 weeks accelerated aging (1 year simulated).

Original languageAmerican English
Pages (from-to)56-65
Number of pages10
JournalFuel Processing Technology
StatePublished - 2018

Bibliographical note

Publisher Copyright:
© 2018

NREL Publication Number

  • NREL/JA-5400-70563


  • Antioxidant
  • Biodiesel
  • Oxidation stability
  • Renewable fuel
  • Storage stability


Dive into the research topics of 'Re-Additization of Commercial Biodiesel Blends During Long-Term Storage'. Together they form a unique fingerprint.

Cite this