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The compounds pillared by heteropolyamon, Zn2Al-SiW11 and Zn2Al-SiW11Z (Z= Co2+ , Cu2+ and Ni2+), were synthesized. The results of XRD, IR, TG-DTA and 27A1 and 29Si MAS NMR studies indicated that they were pillared layered compounds with gallery height 0.99 nm. Layers have significant effect on heteropolyanions in gallery and on the symmetry of Si-O tetrahedron. The order of their thermal decomposition temperature was found as follows: Zn2Al-SiW11Ni ( 347℃) > Zn2Al-SiW11Co (341℃) > Zn2Al-SiW11Cu (335℃ ) > Zn2Al-SiW11 (329℃) > Zn2Al-NO3(290℃ ). In boiling aqueous solution, the stable pH range of these compounds is 3.6-7.5. And their BET adsorption isotherm and the pore size distribution curve were determined. It was found that this kind of micro-porous catalyst had high activity and selectivity for the oxidation of benzaldehyde to benzoic acid using H2O2 as oxidant in liquid-solid biphase system.