Patent ID: 7758756

Claim:
A process for treating a contaminated aqueous solution to remove one or more phosphate anionic contaminants therefrom, comprising: a. contacting the contaminated aqueous solution with a lignocellulose-based anion-adsorbing medium (LAM), wherein the LAM has been formed by the steps of: i. dissociating cations selected from the group consisting of Fe, Al and Ca, from their counterions by adding a chemical compound containing said cations to water and acidifying; ii. pelletizing a lignocellulose having hydroxyl groups (—OH); iii. adsorbing the cations to a lignocellulose having hydroxyl groups (—OH) by bringing the lignocellulose into contact with the solution of step (i) and incubating; and iv. replacing hydrogens (H) of the hydroxyl groups of the lignocellulose with the cations to produce the LAM with a positive charge by exposing the lignocellulose of step (iii) to an alkaline fixing agent; and, b. recovering a treated aqueous solution with reduced content of the phosphate anionic contaminants.