Cellulose based organogel as an adsorbent for dissolved organic compounds

- Organogel adsorbent based on nanofibrillated cellulose was prepared.
- The cellulose organogel was modified by grafting hydrocarbon chains to boost the adsorption capacity.
- The modified organogel showed improved adsorption towards dissolved organic pollutants.
- The cellulose organogel could to be readily regenerated and reused without any loss of the adsorption capacity.

Highly porous cellulose organogels were prepared from nanofibrillated cellulose hydrogels and their adsorption properties towards a wide range of organic pollutants were investigated. Here, we show that by functionalizing the native cellulose nanofibrils of the organogel with the hydrophobic hydrocarbon chains, the adsorption capacity is meaningfully boosted, making possible to use the modified organogel as an adsorbent for organic compounds. The chemical modification was confirmed by infrared spectroscopy (FTIR) and solid NMR spectroscopy. The kinetics and adsorption isotherms of several aromatic compounds, including herbicides were investigated. It was proposed that the adsorption process is the result of the diffusion of the organic solute inside the grafted hydrocarbon chains acting as a reservoir on which the organic compounds would be accumulated. The results showed that the modified cellulose organogels could be easily regenerated and reused without any loss of the adsorption capacity, which constitutes one of the main advantages of this category of the adsorbents derived from a renewable resource.