Water De-Pollution: Different Sorbents for Different Water Pollutants

The occurance of emerging contaminants in water had become an environmental concern since global climate change is causing water to become a scarce resource globally. Veternary antibiotic sulfamethoxazole (SMX) is one of emerging pollutants of interest in this study. The main concern with the presence of antibiotics in aquatic environment is that they can provoke antibiotic resistance which bear ecological and human health risks. Hence, investigations on the adsorption capacity of zeolite Y on SMX in the presence of caffeic acid (CA) and vanillin (VNL) were carried out.The experiments were conducted at room temperature in a wide pH range 5-8. Results indicated that CA is marginally adsorbed by zeolite Y at all pH investigated. Whereas SMX and VA were adsorbed by zeolite Y, the adsorption was inversely affected by pH, adsorption increased as the pH decreases. Both compounds demonstrated a quick kinetics, where these compounds were adsorbed within 1 min. Therefore VNL can compete with SMX for zeolite adsorption sites (i.e. pores). However, since the adsorption of SMX is irreversible whilst that of VNL is reversible, therefore SMX should be retained more firmly by the zeolite. Another water pollutant investigated in this study was heavy metals (Cu and Zn). Water pollution by heavy metals cause both environmental and health problems throughout the world, due to their toxicity and poor biodegradability. The peel waste of banana (BP), orange (OP), pineapple (PP) and potato (PoP) were used as adsorbent. The river water spiked with Cu and Zn were percolated in a 1 g peel glass column. The results indicated that BP adsorbed up to 17.8 and 23.5 mg/g for Cu and Zn, respectively. The eluates of the adsorption experiments were used to grow lettuce on hydroponics. BP eluates significantly obtained higher biomass yield of lettuce leaves and roots compared to tap water.