Zeitschrift für Umweltanalytische Chemie

Insights into the Eco-Friendly Adsorption of Caffeine from Contaminated Solutions by Using Hydrogel Beads

Abstract

Aharon Zarzar, Minyeong Hong, Bertha P Llanos and Abel E Navarro

The presence of drugstore products in water streams has become a major concern in environmental remediation. Preliminary studies have reported that caffeine has negative impacts in animals and ecology in general. Bioremediation emphasizes on the elimination of heavy metals and toxic organic pollutants, but little attention has been paid to the so-called pollutants of emerging concern (i.e. caffeine). This research evaluates the role of pH, adsorbent dose, salinity and time on the elimination of caffeine from aqueous solutions by using chitosan and alginate hydrogel beads. Experimental data indicates a strong pH effect on the adsorption, showing its highest values around neutral conditions. On the other hand, salinity has a negative effect on the adsorption, due to competition for the adsorption sites of both hydrogels. Finally, time dependence experiments demonstrate that less than 20 minutes are needed to reach adsorption equilibrium. These results suggest that biodegradable and cost-effective materials are good candidates for the removal of pollutants of emerging concern from contaminated waters.