Patent ID: 7968493

Claim:
A method for the preparation of adsorbent compositions for removing pesticides like chlorpyrifos, malathion and other organo halogen/sulphur pesticides comprising metallic gold/silver nanoparticles having a size which is up to 150 nm deposited on activated alumina and/or magnesia, wherein said metallic gold/silver nanoparticles are prepared by: (a) diluting silver nitrate or HAuCl 4 3H 2 O in water to form a solution; (b) heating the solution from step (a); (c) adding a sodium citrate solution to the solution from step (b); (d) heating the solution from step (c) to produce a solution containing silver or gold nanoparticles; (e) soaking activated alumina and/or activated magnesia in the solution from step (d) to produce activated alumina and/or activated magnesia loaded with gold or silver nanoparticles; and (f) washing the loaded activated alumina and/or activated magnesia from step (e) with distilled water.