Analysis of Sodium & Potassium in Fatty Acid Methyl Esters (FAME)

Introduction

Fatty acid methyl esters (hereafter, FAME) standardized as biodiesel fuel would contain Na and K due to the catalyst, etc. used during production. When these are present in excess, problems occur because they help form solids and metallic soaps, which adhere to the engine fuel injector interior and valves, and block the fuel filter . Therefore, there is a standard for the total content of Na and K in FAME that is used in biodiesel fuel, specifying that the concentration must not exceed 5 mg/kg (European Standard EN14214, etc.). One of the methods specified in EN14214 for the analysis of Na and K is the flame atomic absorption method. The test methods actually used are EN14108 and EN14109. This Application News introduces an example of determination of Na and K in FAME produced from palm oil and coconut oil, using the flame atomic absorption method.

April 30, 2008 GMT