KEROLITE-STEVENSITE MIXED-LAYERS FROM THE MADRID BASIN, CENTRAL SPAIN

Structural features of very highly disordered 2:1 trioctahedral phyllosilicates from the Madrid Basin have been studied. Application of Fourier methods to XRD patterns shows that these materials consist of random kerolite-stevensite mixed-layered phases (R = 0) with 50-80% kerolite layers, and have a very small particle size with a mean of three unit-cells stacked in the c* direction. IR spectrum deconvolution in OH-stretching and librational modes seems to indicate five different types of water. Specific surface measurements (N2, BET) indicate anomalous high values (240-320 m2/g). These results suggest important catalytic and surface chemistry applications.