Ricerc@Sapienza

The new mineral species rüdlingerite, ideally Mn2+2V5+As5+O7·2H2O, occurs in the Fianel mine, in Val Ferrera, Grisons, Switzerland, a small Alpine metamorphic Mn deposit. It is associated with ansermetite and Fe oxyhydroxide in thin fractures in Triassic dolomitic marbles. Rüdlingerite was also found in specimens recovered from the dump of the Valletta mine, Canosio, Cuneo, Piedmont, Italy, where it occurs together with massive braccoite and several other As- and V-rich phases in richly mineralized veins crossing the quartz-hematite ore.

The gas-phase reactivity of doubly-charged vanadium hydroxides anions with SO2 has been studied by experimental and computational methods. The obtainedresults highlight the role of sulfur dioxide in promoting unprecedented bond-forming reactions, which produce singly-charged products by breaking the VxOy skeleton or a terminal VObond.

The saprotrophic fungus Penicillium griseofulvum was chosen as model organism to study responses to a mixture of hexachlorocyclohexane (HCH) isomers (α-HCH, β-HCH, γ-HCH, δ-HCH) and of potentially toxic metals (vanadium, lead) in solid and liquid media. The P. griseofulvum FBL 500 strain was isolated from polluted soil containing high concentrations of HCH isomers and potentially toxic elements (Pb, V).

Contamination of groundwater by arsenic due to natural processes is rather common worldwide and hinders its use for drinking water supply. In many cases, arsenic contamination is found together with high levels of vanadium and fluoride. Therefore, more than one type of treatment is required to reduce concentrations of all these contaminants below non-hazardous levels so to make the source drinkable. The present study investigated the uptake capacity of arsenic, vanadium and fluoride by three iron-based adsorbent media differing for particle size, iron content and specific surface.