Campanian tuff

The possible use of Campanian tuff, namely chabazite tuff, in the removal of lead from wastewaters has been evaluated, either in static experiments or testing fixed beds eluted by solutions of the pollutant with or without the addition of interfering cations. 

The previous considerations and the knowledge of the high selectivity of chabazite for lead (11) suggest research on the possible use of Campanian tuff (namely chabazite tuff) (12) for lead removal from wastewater. Recent studies have emphasized the good behaviour of the tuff either in equilibrium (E. Torracca, P. Galli, private communication) or dynamic tests, carried out with model solutions of only lead (M. Pansini, C. Colella, to be published). 

The results of the present research allow one to foresee good perspectives on the use of Campanian tuff in lead abatement from wastewaters. Chabazite in fact shows good selectivity for the pollutant, also in the presence of considerable amounts of interfering cations, and high exchange rate. Applications may be expected... 

Fig. 6.10. TAS classification diagram for Campi Flegrei and for buried Pliocene rocks beneath Campi Flegrei (Parete-2 well). Circled fields indicate compositions of the Campanian Ignimbrite (Cl) and Neapolitan Yellow Tuff (NYT) pumices.

Pappalardo L, Civetta L, D Antonio M, Deino A, Di Vito MA, Orsi G, Caran-dente A, De Vita S, Isaia R, Piochi M (1999) Chemical and isotopical evolution of the Phlegraean magmatic system before the Campanian Ignimbrite (37 ka) and the Neapolitan Yellow Tuff (12 ka) eruptions. J Volcanol Geotherm Res 91 141-166... 

---