Fe(III) is reduced by carbendazim to Fe(II) and upon its reaction
with potassium ferricynide a precipitate known as Turnbull ‘s Blue
is produced [29,30]. This product is soluble in acid and in the
presence of methyltrioctylammonium ion as an ion pair is
extracted into carbon tetrachloride. The developed spectrophotometric
method here is based on the extraction of this color
product into carbon tetrachloride in the presence of Aliquat 336.
Aliquat 336 also plays the role of disperser agent which is injected
along with extraction solvent to aqueous solution. In order to find
the appropriate conditions for DLLME, different experimental parameters
were studied and optimized using a carbendazim solution
with a concentration of 500 ng mL1
.