Adsorption properties of tin silicophosphate

Adsorption-desorption isotherms of tetrachloromethane and water vapors were used to characterize the adsorption properties of porous tin silicophospha te prepared by coprecipitation from a solution of activated silicic acid an d SnCl4 at Si : Sn molar ratios from 0.9 : 0.1 to 0.1 : 0.9. The adsorption isotherms obtained are characteristic of micro- or mesoporous adsorbents. The boundary between micro- and mesoporous microstructures lies at Si : Sn = 0.3 : 0.7. The isotherms of water vapor sorption are found to be irrevers ible over the entire range of relative pressures studied.