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For the first time, a set of samples of European flue gas cleaning residues, mainly from the incineration of municipal solid waste (MSW), has undergone a mineralogical study. The residues are the result of the neutralization of acid flue gases by lime, the predominant method adopted in Europe, using dry and semi-dry washing processes. The study protocol combines physico-chemical analytical techniques (XRD, FTIR, DSC/TGA) and global chemical analysis enabling identification of the chemical composition of the main constituents, particularly chlorinated Ca-based phases, as well as establishment of modal distributions of the represented phases, both crystalline and amorphous. The samples are slightly hydrated and values vary for trapped Cl, S and even CO(2). The main crystalline phases are NaCl, KCl, CaSO(4), CaCO(3), Ca(OH)(2) and calcium hydroxychloride CaOHCl. CaOHCl is the main chlorine phase, regardless of the treatment process, filtration mode, and specific surface of the Ca-based sorbent. This phase develops during neutralization of HCl by excess lime present according to the reaction Ca(OH)(2)+HCl-->CaOHCl+H(2)O, to the detriment of a complete yield involving the two lime OH groups with formation of CaCl(2).2H(2)O. In addition, it seems that gas temperatures above 150 degrees C increase competition between lime-based neutralization of HCl, SO(2) acid flue gases and CO(2) trapping, thus reducing washing efficiency.

A new vanadium iron oxide has been synthesized starting from V 2 O 5 xerogel through an exchange reaction. In its Rietveld-determined structure, (FeO 6 ) apex sharing octahedra link V 2 O 5 ribbons and increase the three-dimensional character of the material. This latter point seems to improve the electrochemical behaviour when compared with V 2 O 5 . Especially, in terms of cycle life, a capacity of 210 Ah/kg is maintained after 40 cycles in the potential window of 3.8-2 V instead of 150 Ah/kg for V 2 O 5 .

Possible sites for lithium intercalation in prelithiated α-MnO2 compounds are studied by electrochemical techniques. Two types of behaviour, corresponding to different lithium localizations in the prelithiated material are evidenced and they give different electrochemical capacities.