Diphenylthiocarbazone (dithizone), 2.56 g (~10.0 mmol), as the
organic modifier was weighed and transferred to a 500 ml conical
flask and completely dissolved by heating at ~50 °C in 400 ml of ethyl
alcohol. To this solution 10.0± 0.1 g of alumina adsorbent, either
acidic, neutral or base, was added and the reaction mixture was
further stirred at this temperature for 6 h