Last updateFri, 23 Feb 2024 1pm

Back You are here: Inicio Agro-food technologies Technological offers Rice straw and pine wood as filters for water treatment

Rice straw and pine wood as filters for water treatment

A CSIC team has developed a process to manufacture activated carbon filters from rice straw and wood shavings. The process makes it possible to obtain more efficient filters than conventional ones for the elimination of emerging organic pollutants in water. Companies interested in licensing the patent are being sought.

Microscope images of activated carbon obtained from rice straw and pine wood (IRNAS-CSIC)

In last years, one of the most demanded applications of activated carbon is its use in water treatment processes. Due to their high adsorption power, these filters contribute to the removal of organic pollutants from water.

In general, all activated carbon synthesis processes involve two well-defined stages. The first is the carbonisation or pyrolysis of the precursor, and the second is the activation of the carbon. For the latter, chemical activation is the most common procedure.

The disadvantage is that, although effective, chemical activation releases highly reactive and harmful gases. Besides, once the process is finished, it is necessary to ensure that the activating chemical is removed.

The process developed by the team led by Tomas Undabeytia, researcher at the Institute of Natural Resources and Agrobiology (IRNAS-CSIC), in Sevilla, is based on an initial stage of pyrolysis of rice straw and recycled pine wood chips in the absence of oxygen, and a second stage of physical activation instead of chemical activation. As the second stage does not use oxidising chemical agents, no reactive gases are released and no subsequent step for removing the activating substance is necessary. The result are activated carbon filters in granular form with a high purification capacity in a sustainable way.

It makes possible to recycle and recover waste biomass of little commercial value

The scientists highlight that this method makes it possible to recycle and recover waste biomass of little commercial value, and that it is a safer process from the operational point of view as well as more environmentally sustainable.

The activated carbon obtained has more retention sites for organic pollutants per unit weight than commercial granular activated carbons enabling a higher performance in the removal of organic pollutants (neutral, anionic and cationic).

The material developed has a particular impact on emerging pollutants, which even in very low concentrations can be harmful to health.


Cristina Villodres Ruiz
Vicepresidencia de Innovación y
Transferencia - CSIC
Tel.: 954232830 ext. 434809
This email address is being protected from spambots. You need JavaScript enabled to view it.