Investigation into the desulphurization properties of by-products of the manufacture of white marbles of Northern Tuscany

The desulphurization properties of calcium hydroxide samples obtained from some by-products of the manufacture of the white marble of Northern Tuscany, are better than those obtained from commercial limestone. This behaviour is basically related to a larger BET surface area and with a suitable pore size distribution of the CaO obtained in the high temperature treatment of the Ca(OH)2. Moreover, the presence of a small amount of iron increases the reactivity of the samples also in close relation with the eventual presence of NOx in the treated gas. The tested marble by-products can be classified as secondary base materials.