Both of the dry ashing techniques, that is, dry ashing
with H2SO4 and dry ashing with Mg (NO3)2, turned out
to be very efficient for the determination of As, Cu, Fe,
and Pb in white sugar by FAAS. So far, these two
methods seem to be the only ones available for these
determinations using a single ashing procedure. Between
these two, the ash produced in the Mg(NO3)2
method is difficult to handle and the duration of
digestion is longer compared to that of H2SO4 applications.