Preparation and characterization of 5-sulphosalicylic acid doped tetraethoxysilane composite ion-exchange material by sol-gel method.

•Sulphosalicylic acid doped tetraethoxysilane composite is prepared by sol–gel method.•Its X-ray diffraction studies suggest that it is crystalline in nature.•This material shows selectivity for Mg(II) and Ni(II) ions in aqueous solutions.•Separation of Ni(II) from binary mixtures was successfully achieved on this material.