Abstract: A functionalized silica is prepared by reacting silica with a silane and an aromatic hydroxy aldehyde. The product is useful for removing metals from solution, e.g., Cu from ATK, or in the extraction of U from solutions arising from the processing of its ores.

Abstract: The invention relates to an esterification process employing as a heterogeneous catalyst an inorganic oxide, e.g. silica, to which there is bonded by reaction with surface hydroxyl groups a sulphonic acid-functionalized silane.

Abstract: A functionalized solid product containing sulphonate or sulphonic acid groups is prepared from an inorganic oxide containing surface hydroxy groups, e.g. silica by reacting the latter in a first stage with a haloalkyl alkoxy- or aryloxysilane. The first stage product is then reacted with an aqueous solution of an inorganic sulphite to give a product containing sulphonate groups. These can be converted to sulphonic acid groups by an optional third stage treatment with dilute mineral acid. The final products are suitable for use as adsorbent materials or catalyst supports.

Abstract: A process for the removal of heavy metals uranium and transition metals other than noble transition metals from solution by contacting the solution with the product obtained by reacting an inorganic solid eg. silica gel containing surface hydroxyl groups with a silicon compound of defined formula containing a free thiol group or a free amino group and either an --OR group or a halogen atom under conditions which effect reaction between the hydroxyl group and the --OR group or halogen atom thereby bonding the silicon compound to the inorganic solid.