INTRODUCTION

Pharmaceutical residues are today a relevant topic in the field of environmental technology. There are many different investigations regarding the fate of various pharmaceuticals, but the main emphasis is currently on the removal of these residues. The focus is to prevent the harmful effects of these residues, because we can foresee what chemical substances are formed by different kinds of residues.

The aim of this research was to study the removal potential of three common pharmaceuticals with powdered activated carbon (PAC): nonsteroidal inflammatory drug diclofenac (DCF) and two antibiotics, sulfamethoxazole (SMX) and levofloxacin (LFX). To this end, different adsorption batch experiments were determined, which provide information for process engineers in discovering activated carbon treatment steps.

METHODS

For batch experiments, different solutions were prepared with ultrapure (ELGA) water and a known concentration of the pharmaceuticals under investigation. The concentration was measured as a TOC (total organic carbon). 100 ml of the solutions and 0.05 g of PAC were mixed and a sample was taken in intervals of 5, 10, 30, 60 and 120 minutes (when a stable value was achieved) in order to determine the adsorption capacity dependant on time. The same experiment was then repeated to discover the removal effectiveness and removal capacity, though different concentrations of PAC were added.

The best results were achieved in LFX removal, DCF and SMX need a higher amount of PAC to remove the same quantity of drugs. These results give us important input data for future process design. The next step would be an onsite experiment with a pilot plant.

DOI: https://doi.org/10.3846/enviro.2017.082