RESUMOSete perfis de solos do entorno do Aterro Sanitário da Caximba em Curitiba-PR, foram coletados para caracterização e quantificação dos minerais da fração argila e determinação dos teores totais e trocáveis de Cr, Ni, Cu, Zn e Pb. A fração argila foi estudada por difratometria de raios-X, análise térmica e extrações químicas com oxalato de amônio, ditionito-citratobicarbonato de sódio. ABSTRACTSeven soil profiles were collected around Caximba Landfill, in Curitiba -PR, to characterize and quantify clay fraction mineral and to determine total and exchangeable Cr, Ni, Cu, Zn and Pb contents. Clay Fraction was studied by x-ray diffractometry (XRD), thermal analysis and chemical extractions with ammonium oxalate (AO) and sodium dithionite-citratebicarbonate (DCB). Heavy metals total and exchangeable contents were determined by atomic absorption spectrophotometry, after sample acid digestion (H 2 SO 4 , HF, HNO 3 e HClO 4 concentrated) and extraction with BaCl 2 1 mol dm -3 , respectively. The predominance of kaolinite, which varied between 548,5 to 702,1 g kg -1 , and the occurrence of vermiculite with hidroxi between layers in clay fraction, determined the soils relatively high CEC. Iron oxide contents were low, making the nature of the parent material evident (granite/gneiss and clay-silt sediments) and the Fe reduction conditions and removal to soils under hydromorphism influence. In a general way, increase of heavy metals contents around Caximba Landfill soil was observed. Although, contamination levels were not very expressive, related to the low concentrations of Cr, Ni, Cu, Zn and Pb in leachate; leaching facility in hydromorphic soils; high divalent and trivalent cation contents (Ca 2+ , Mg 2+ e Al +3 ) in sorptive soil complexes.

Abstract Abstract: In order to characterize and to quantify the minerals of the clay fraction and to evaluate the contamination by lead (Pb) caused by effluents from a recycling company of waste batteries in Paula Freitas, Paraná state, Brazil , samples of low land soil were collected from five profiles. Besides the total levels, the soil samples were submitted to sequential chemical analyses for the determination of different Pb forms: soluble, exchangeable, linked to organic matter, linked to alluminiun and iron oxides and residual. The clay fraction, studied by X-ray diffraction and differential thermogravimetric analysis, presented high levels of kaolinite and small amounts of gibbsite, amorphous material and goethite.