| The montmorillonites pillared with Ti and/or other metallic cations have been proved to be one of the most interesting materials at home and abroad. They are widely used in the fields such as catalysis, catalytic supports, selective sorbent, molecular screen, film, electrochemistry, optical element, zymic counterfeit and dyestuff base materials for their good properties of large BET surface area, porosity and large surface activity.The paper was aimed to study the influencing factors of materials in the preparation process, and approach the phase transition of TiO2 in such porous materials. In this paper, Ti-PLMs were prepared by two kinds of methods, hydrolytic decomposition method (TiCl4 as the titanium source) and Sol-Gel method ( Ti(OC4H9)4 as the titanium resource ). Composition, structure and properties of the pillared montmorillonite were studied with the means of spectrophotometry, XRD, SEM, DTA, FT-1R etc. The optimization conditions of preparation by the hydrolytic decomposition method are 4.0mol/L for [HCl]0, 0.4mol/L for [HCI]P, 0.82mol/L for [TiCl4]p, about 40mmol/L for [HCl]m, about 80mmol/L for [TiCl4]m , 20mmol/g for Ti/clay, 24 hours for aging time of pillaring solution, and 48 hours for aging time of mixed suspension. The optimization conditions of the Sol-Gel method are 1:4 for the molar ratio of Ti(OC4H9)4/H2O, 20mmol/g for the ration of Ti/clay. The surface area of Ti-PLMs is in the -range of 179-277.5 m2/g , 5-8times larger than one of Na-montmorillonite . Pore sizes of Ti-PLMs are dominated by 0.9nm pores, which have been believed to be the micropore of two-dimension pore canal, and contain some pores of 1.4-3.4nm, which are mesopore or macropore of house-of-cards-like. The temperature of phase transition from anatase to rutile is about 650℃. Strong Bronsted acid site ( 1540, 1636cm-1 ), Lewis acid site ( 1445, 1610 cm-1 ) and overlying acid site of Bronsted and Lewis ( 1490cm-1 ) are presented in pyridine-saturated Ti-PLMs.
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