• Method adopted/last revised:
• Method reapproved: None
• REF/ISBN:
• Status: Current
• First printed in STM books: June 2021

This   document   specifies   a   method   for   the identification  and  quantification  in  the   range  4,5 mg/kg to 150 mg/kg of selected fatty acid methyl ester  (FAME)  species,  see  Table  1, in  aviation turbine fuel (AVTUR).

NOTE 1 - AVTUR (and AVTUR contaminated with diesel/ biodiesel)  can  contain  some  high  molecular weight naphtha  components  which  may  mask  the  FAME  at very low levels. Low carbon number methyl esters, such as  those  derived  from  coconut  oil,  may  be  subject  to interference from AVTUR components and may not be quantified at low levels.
NOTE 2 - The FAME species listed in Table 1 have been specifically chosen as they typically make up greater than 95 % of the composition of the major biofuel feedstocks currently  used  in  biodiesel blends  with  conventional mineral  diesel.  In  addition  methyl  heptadecanoate  is included as it may be present in animal fats.

NOTE 3 - In the round-robin study, two samples were blended containing no  FAME.  No  positive   biases  were found in either the Merox treated or hydrotreated fuels used in the round robin.