Specific Surface Area by Colorimetry and Image Analysis

Abstract

Specific surface area is more informative than grain size for fine-grained sediments where 13 S s >1m 2 /g. In fact, specific surface area plays a central role in engineering properties and processes 14 in fine-grained soils including pore size and bioactivity; fabric, plasticity and rheology; hydraulic 15 and electrical conductivity; compressibility and residual friction angle; and all forms of coupled 16 processes. This research advanced a dye adsorption method using digital image colorimetry 17 implemented with smartphone technology. In particular, adopted a water-based approach to reach 18 internal surfaces in platy phyllosilicates, selected short dye molecules to reduce the range of potential 19 molecular contact area, and developed a physics-based adsorption model to analyze the complete 20 dataset to minimize the uncertainty in specific surface area determinations. The study involved fine-21 grained soils with distinct mineralogy and specific surface area (from 1 to 600 m 2 /g), and various 22 cationic dyes and a protein to explore the effect of molecular size and shape and pH effects. Crystal

On the Pore Geometry and Structure Rock Typing

“…Specific surfaces of in situ soils are fabric- and stress-dependent. Therefore, we assume that specific surfaces measured under atmospheric conditions are adequate (the methylene blue method in ref , image analysis method in ref ). Standard methods for specific surface determination in rocks include BET methods with N 2 , Ar, or He gases or from analysis of mercury intrusion data. , …”