Biosorption of ibuprofen from aqueous solution using living and dead biomass of the microalga Phaeodactylum tricornutum

Ibuprofen has become an emerging pollutant in aquatic ecosystems, and therefore, it is necessary to develop efficient methods for its elimination. Bioremediation based on the use of a biological material as sorbent is a good alternative. For this reason, the sorption characteristics of ibuprofen using living or dead biomass of the microalga Phaeodactylum tricornutum have been tested in this study. Kinetics, isotherms, and maximum sorption capacity were investigated and discussed. Both living and dead biomass showed a similar efficiency; around 99.9% of ibuprofen was removed even when the initial concentration of ibuprofen tested reached 2 mg L−1 and 0.8 g L−1 of biomass used. Based on the Langmuir isotherm, the maximum sorption capacity was 3.97 mg g−1 at 18 °C, agitation speed 200 rpm, and pH 8.2 after 6 h of contact time. Results indicated that the removal efficiency increased as pH decreased and was higher at pH 2. Six consecutive sorption-regeneration cycles were assayed, and after 3 cycles, there was a loss of only 10.7% in efficiency, which remained stable thereafter. Therefore, the results indicate that the biomass of this microalga is a good and eco-friendly alternative for applications that require the removal of ibuprofen from aqueous solutions.