You can start adsorption method by activated carbons which can be prepared from different raw materials, such as sugarcane bagasse, coconut (Cocus nucifera) shells and so on, to remove moisture. However, the adsorptive properties of the activated carbons can measure by gas adsorption (BET method), using an ASAP 2010 porosimeter, and liquid phase adsorption. The activated carbon from sugarcane bagasse will gives 100% capability as an adsorbent to remove pollutants.

For further references, you can also read the attached files.

Thank you. Your answers were of great help. 

May I add one thing: activated carbons are not necessarily molecular sieves: extremely narrow pore-size distributions (PSD) are required, that cannot be obtained from any activation method. The burn-off must be very well controlled before the PSD starts to broaden, leading to normal activated carbons, not molecular sieves ....

Alain

 You might also consider alkaline peroxide treatment, similar to what we did with straw. (See attached paper). We found that the treated straw was much more water-absorbent, and behaved like a porous gel-filtration matrix.