Montan waxes from brown coal must be
deresinified, oxidatively bleached, and esterified
(optional) [4], [5]. Oxidation of the waxes consists
of several consecutive reactions; the first
three steps (oxidation of resins and dark- colored
substances, saponification of montan waxes, oxidation
of wax alcohols) are desirable, whereas
the fourth (oxidative degradation of wax acids)
is not