Synthetic wastewater treatment of anticancer agents using synthesized hydrophilic silica aerogels

Abstract

ABSTRACT In this study, the synthesis and use of highly efficient hydrophilic silica aerogels to remove cytotoxic chemotherapy drugs, Daunorubicin (DAU) and Doxorubicin (DOX), from synthetic pharmaceutical wastewater are reported. DOX/DAU Adsorption studies revealed the high adsorption capacity of the hydrophilic sample. Optimal adsorbent dosage and solution pH for DAU/DOX adsorption was 0.15 g and pH = 10, respectively. Results of kinetic studies demonstrated that the equilibrium time for DAU/DOX adsorption was within 60 minutes, and the pseudo 2nd order model best fitted to the adsorption experimental data. The results of the intra-particle diffusion model showed that the DAU/DOX adsorption process occurs in two stages. The adsorption rate of the first stage is high, and in the next slower stage, the diffusion of particles is controlling stage, and the external diffusion plays an essential role in the adsorption kinetics. Langmuir isotherm best fitted to the experimental data in comparison to the Freundlich isotherm, and it could be stated that the adsorption of DAU/DOX on silica aerogels preferably follows a monolayer process. The current study revealed that adsorption using hydrophilic silica aerogel is a cost-effective process due to relatively low cost precursors and suitable alternative for removing chemotherapeutic drugs from wastewater.