Paper Title
Effective Removal of Emerging Contaminants from Drinking Water using Powdered Activated Carbon: A Comparative Study

Abstract
The widespread and adverse health-related and environmental impacts of different types of emerging contaminants in water resources have become a global issue of concern. On the other hand, the ever increasing socioeconomic awareness, scientific knowledge, ecological apprehensions and health-related problems, people are more concerned about the widespread of emerging contaminants in water resources globally. Regulatory frameworks and toxicological studies require these compounds to be removed from water prior utilization by living organisms including humans. In this study, the effectiveness of different powder activated carbon on the removal of emerging contaminants (ECs) from drinking water was comprehensively evaluated. Real raw water samples were collected from the river that feeds the 12 ML/d drinking water treatment plant. Optimization studies was done using jar stirrers and specifically the one factor at a time. Effect of dosage was assessed as a preliminary appraisal. High-pressure liquid chromatography-mass spectrometry (HPLC-MS) was used to determine the levels of ECs. Assessed ECs comprise Sulfamethoxazole, Carbamazepine, 1.7 Dimethylxanthine, Tramadol, and Venlafaxine. Findings from this study successfully confirmed the removal of selected emerging contaminants from drinking water. The obtained results displayed a better performance when the powder activated carbon dosage was increased between 20 – 100 mg/L. A100% removal efficiency was achieved for Sulfamethoxazole at 20 mg/L; Carbamazepine at 40 – 60 mg/L;Venlafaxineat 40 – 80 mg/L and Tramadolat 40 – 100 mg/L.During comparisons of the two activated carbons, obtained results showed that the Sulfamethoxazole was removed on both occasion at the same dosage, i.e., 20 mg/L, followed by Carbamazepine in different dosage points of 40 mg/L (ARG PAC) and 60 mg/L (Conventional PAC), then Venlafaxine in different dosage points of 40 mg/L (ARG PAC) and 80 mg/L (Conventional PAC), Tramadol in different dosage points of 40 mg/L (ARG PAC) and 100 mg/L (Conventional PAC) and between 90 – 97% removal efficiency of 1.7 Dimethylxanthine was achieved at dosage points of 100 mg/L on both occasions (ARG PAC and Conventional PAC).Overall, the ARG PAC (commercial PAC) performed efficiently as compared to PAC (Conventional PAC) used at the water treatment plant. From the performed jar test experiments, the obtained results showed that 1.7 Dimethylxanthine was not completely removed but it reported ≥95% removal efficacyin 100 mg/L. However, with the increase in dosage, better removal was obtained. This might be due to the nature of the physical and chemical properties of the 1.7 Dimethylxanthine and its affinity to PAC. Henceforth, the obtained results show that PAC can be used to completely remove selected emerging contaminants from drinking water. In light of the obtained results, it is imperative to optimise operational conditions such as contact time in order to obtain the most efficient and effective removal of ECs from drinking water. Keywords - Water Treatment Plant, Emerging Contaminants, Powder Activated Carbon, High-Pressure Liquid Chromatography-Mass Spectrometry, Adsorption