Journal of the Korean Society of Mineral and Energy Resources Engineers ISSN:2288-0291(Print) 2288-2790(Online) 한국자원공학회지

Dioctahedral smectite was syntheized from dickite by a hydrothermal method at 290℃ under the pressure of 70 kgf/cm2 for 72hours. The crystallization of smectite was favoured by heating of starting material at 800℃. The synthesized smectite was characterized by XRD, IR, TG, DTA, SEM, TEM, EDS, XRF and ICP. IR spectrum of synthesized smectite exihibited Al-O-H bending vibration of 818 and 770cm-1 which was typical for pure beidellite. The formation mechanism of beidellite from dickite appears to be the dissolution and recrystallization process. The addition of seed in the hydrothemal reaction increases the crystallinity of the product noticibly, suggesting the syntaxial growth process. EF-TEM showed ring patterns at 4.43, 2.52, 2.22, 1.67, 1.47, 1.27, 1.23Å and showed 10.0Å parallel lattice images that coincided with the basal spacing of dehydrated beidellite. The CEC, Methylene Blue Dye and swelling capacity were determined to be 116-118 cmol/kg, 84-91% and 29-32 ml/2g, respectively. The chemical composition of the synthesized phase was identified as Na0.5Al2.5Si3.5O10(OH)2 from EDS and XRF analysis.