Synthesis and properties of titanium oxide cross-linked montmorillonite

Abstract-- Titanium was introduced into the montmorillonite s ructure by cation exchange with polymeric Ti cations, formed by partial hydrolysis of TIC1, in HC1. On further hydrolysis and heating, TiO2 pillars in the form of anastase were formed between the montmorillonite layers. The resulting TiOE-Cross-linked montmorillonites po sessed surface areas in the range 200-350 m2/g and pore volumes of about 0.2 cm3/g and were thermally and hydrothermally stable to 700 ~ The basal spacing of products heated at tem-peratures>200 ~ was about 28/~, as determined byX-ray powder diffraction and by N2-desorption pore-size analysis. The surface area increased and the pore volume decreased with increasing HCl-concentration in the Ti-solution. The uptake of TiO2 by the montmorillonite, he surface area, and the pore volume increased with increasing amount of Ti added in the preparation, to about 10 mmoles of Ti/g of mont-morillonite. A further increase in the amount of Ti added resulted in a decrease in surface area, but the pore volume and the uptake of TiO2 remained almost constant. The high porosity and the interlayer spacing of the product are consistent with a structure similar to that previously proposed for smectites, cross-linked with hydroxy-A1 oligocations