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Dusts emitted by an important pyrometallurgical lead smelter have been sampled within the pipes of the grilling and furnace working units before and after the filtering systems, respectively. Particle size distribution, elementary analyses, and X-ray powder diffraction analysis indicate PbS, PbSO 4 , PbSO 4 ‚PbO, Pb, ZnS small particles less than 5 µm in size to contribute mainly to the current atmospheric pollution. Although at least 90% of dust are retained on the filters, the amounts of the respirable smaller particles are significantly larger in the current emission. The average chemical speciation was found to be analogous for the dust samples collected before and after the filters. The scanning electron microscopy associated with energydispersive X-ray analysis and Raman microspectrometry established the morphology and chemical composition at the level of individual particles.

Inorganic chemistry Z 0100 Structures and Oxide Mobility in Bi-Ln-O Materials: Heritage of Bi2O3 -[130 refs.]. -(DRACHE*, M.; ROUSSEL, P.; WIGNACOURT, J.-P.; Chem. Rev. (Washington, D. C.) 107 (2007) 1, 80-96; Unite Catal. Chim. Solide, CNRS, Ec. Natl. Super. Chim. Lille, F-59652 Villeneuve d'Ascq, Fr.; Eng.) -Schramke 16-225

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The binary system PbO-BiV04 exhibits two new phases, Pb,BiV08 and Pb2BiV06. They both melt congruently at 780 "C. They haye been identifi!d by single-cry?tal and powder X-ray diffraction. Pb4BiV08 crystallizes with a triclinic cell, a = 6.221 (2) A, b = 7.603(5) A, c = 10.457(4) A, a = 100.40(3)", p = 102.1 8(2)", y = 90.03(3)" and Z = 2. Pb2BiV06 exhibits four phase transitions at 300, 4105, 475 and 600 "C. The a phase, room-temperature form, is monoclinic with a = 7.642( 6) A, b = 5.81 265, A, c = 28.85j2) A, p = 100.3(1)" and Z 8. The p and . y phases are ythorhombic with a = 8.381 (6) A, b = 16.65(1) A, c = 4.859(6) A, Z= 4 and a = 14.304(7) A, b = 10.1 4(1) A, c = 9.923(4) A, Z = 8, respectively. The 6 phase is tetragonal with a = 12.1 1 O(2) A, c =9.472(8) A and Z=8.Bismuth-based mixed oxides exhibit a wide variety of structures and display physical properties such as ionic conductivity or non-linear properties (ferroelectricity etc). Our previous investigations of binary oxide systems including Bi,03-P20, ,' Bi20,-Pb0,2 Pb0-V205,3 Bi,03-V2054 and B~,O,-AS,O~~ have highlighted a potential interest in extending this work to ternary systems such as Bi,03-PbO-M205 ( M = V, P, As). The investigation with M = V is under progress. This paper describes partial results concerning the PbO-BiV04 binary system which exhibits the known PbBiVO, phase6 and two new phases, Pb2BiV06 and Pb4BiVO8.