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Ciprofloxacin hydrochloride (CIP) is the second generation of fluoroquinolone antibiotics whose residues are found in wastewater and surface water. CIP has high aqueous solubility under different pH conditions and high stability in the soil system. In this study, bentonite was used as a potential sorbent for the removal of CIP from aqueous solutions using batch experiments. The effects of various parameters such as contact time, pH, adsorbent dosage, agitation speed, ionic strength and initial concentration of CIP in aqueous solution on the adsorption capacity were investigated. The optimum contact time, pH, agitation speed and adsorbent dosage were found to be 30 min, 4.5 pH, 150 rpm and 2.5 g L(-1), respectively. When the ionic strength was increased from 5 to 50 mM, the adsorption of CIP decreased from 97.8 to 93.4%. The isotherm adsorption data fitted well with the Langmuir model, Kl and qe were found to be 0.27 L mg(-1) and 147.06 mg g(-1), and the data fitted well with the pseudo-second order kinetics, whereby k was found to be 2.19 g mg(-1) h(-1).

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Microplastics and heavy metals represent two pollutant classes which have adverse impacts on aquatic ecosystems. This study has investigated the adsorption of two heavy metals [Lead (Pb)II and Aluminum (Al)III] on three different types of microplastics [polyethylene terephthalate (PET), polyamide (PA), ethylene vinyl acetate (EVA)]. The Scanning Electron Microscope (SEM) analysis has shown that microplastics have different surface characteristics. The effects of parameters such as the pH of solution, duration of contact, initial concentration and temperature on adsorption capacity have been examined. Experimental results have been applied to the adsorption isotherm models of Langmuir and Freundlich and it has been seen that the Freundlich model has been seen as more suitable than the Langmuir model. Moreover, the pseudo-second kinetic has been found to be more appropriate than the pseudo-first kinetic model. Adsorption percentages have changed according to the type of microplastic and working conditions. Finally, the study has investigated the potential of microplastics to act as an instrument of transport for heavy metals to the food chain and for their bioaccumulation.