TY - JOUR
T1 - Model calculation of sepiolite surface areas
AU - Hibino, Toshiyuki
AU - Tsunashima, Atsumu
AU - Yamazaki, Atsushi
AU - Otsuka, Ryohei
PY - 1995/8
Y1 - 1995/8
N2 - In general, the N2-BET surface areas of sepiolite samples range from 95 to 400 m2/g depending on deposits. The surface areas of five sepiolites, all varying in crystallite size, were measured on heating, and were compared with a model calculation. A sharp decrease in the surface area, due to crystal folding, was observed between 200° and 400°C. Both before and after the folding, each sepiolite sample had peculiar values. Our model sufficiently explains this difference in surface areas among the samples. In the model, which is based on the Brauner-Preisinger structural model, surface area is a function of the crystallite size and the ratios of the coverage for nitrogen adsorption on both the internal and external surfaces. These ratios of the coverage can be inversely estimated from the model. The ratios of the coverage on the internal surface are less than 0.19, and that on the external surface between 0.7 and 1.0
AB - In general, the N2-BET surface areas of sepiolite samples range from 95 to 400 m2/g depending on deposits. The surface areas of five sepiolites, all varying in crystallite size, were measured on heating, and were compared with a model calculation. A sharp decrease in the surface area, due to crystal folding, was observed between 200° and 400°C. Both before and after the folding, each sepiolite sample had peculiar values. Our model sufficiently explains this difference in surface areas among the samples. In the model, which is based on the Brauner-Preisinger structural model, surface area is a function of the crystallite size and the ratios of the coverage for nitrogen adsorption on both the internal and external surfaces. These ratios of the coverage can be inversely estimated from the model. The ratios of the coverage on the internal surface are less than 0.19, and that on the external surface between 0.7 and 1.0
KW - Heat treatment
KW - Model calculation
KW - Sepiolite
KW - Surface area
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U2 - 10.1346/CCMN.1995.0430401
DO - 10.1346/CCMN.1995.0430401
M3 - Article
AN - SCOPUS:84904818696
VL - 43
SP - 391
EP - 396
JO - Clays and Clay Minerals
JF - Clays and Clay Minerals
SN - 0009-8604
IS - 4
ER -