DECOLOURIZING  , in

practical chemistry and chemical technology, the removal of coloured impurities from a substance . The agent most frequently used is charcoal, preferably prepared from blood, which when shaken with a coloured solution frequently precipitates the coloured substances leaving the solution clear . Thus the red colour of wines may be removed by filtering the wine through charcoal; the removal of the dark-coloured 1 At the 7th plenary sitting of the second Hague Conference (September 7th, 1907) the chiefs of the Spanish and Mexican delegations, M. de Villa Urratia and M. de la Barra, announced the determination of their respective governments to accede to the Declaration of Paris . 2 This relates to the incident in the Russo-Japanese War of the transformation of Russian vessels which had passed through the Dardanelles unarmed . impurities which arise in the manufacture of sugar may be similarly effected . Other " decolourizers " are sulphurous acid, permanganates and manganates, all of which have received application in the sugar industry .