RT Journal Article
T1 Spanish palygorskites: geological setting, mineralogical, textural and crystal-chemical characterization
A1 Suárez, Mercedes
A1 García Rivas, Javier
A1 Sánchez Migallón, Juan Morales
A1 García Romero, Emilia
AB A representative group of palygorskites from the six most important Spanish deposits and six other occurrences were studied comparing their mineralogy, textural features, crystal-chemistry, and surface properties. These palygorskites have different geological origin: (1) sedimentary in large Tertiary continental basins, (2) hydrothermally altered volcanic rocks in the southern Spanish Peninsula, also Tertiary in age; and (3) fault-hosted pure palygorskites. The most common impurities are quartz and carbonates, both calcite and dolomite, but also feldspar, illite, smectite, and sepiolite have been identified. The structural formulae obtained show great variability between samples, as well as with respect to the theoretical formula for palygorskite, as they range from magnesian to aluminous palygorskites. The most common fibre length ranges between 1 and 10 µm but the palygorskites of hydrothermal origin are much longer, with lengths over 10 µm. The shorter fibres give rise to tightened textures, while longer fibres usually generate more open textures. These properties, along with the degree of compaction, condition the porosity of the sample, which in turn influences its surface properties. The specific surface areas obtained range between 30 m2 g−1 and 263 m2 g−1, depending on the impurities content and on the texture and crystal-chemistry; the highest values correspond to Mg-rich palygorskite.
PB E Schweizerbart Science Publishers
SN 0935-1221, ESSN: 1617-4011
YR 2018
FD 2018
LK https://hdl.handle.net/20.500.14352/18712
UL https://hdl.handle.net/20.500.14352/18712
LA eng
NO MINECO
DS Docta Complutense
RD 3 oct 2024