Novel Agricultural Waste Adsorbent,Cyperus rotundus, for Removal of Heavy Metal Mixtures from Aqueous Solutions

Abstract

An agricultural waste, Cyperus rotundus (CR), was used as a low-cost adsorbent to remove two toxic heavy metal ions (copper [Cu] and zinc [Zn]) from aqueous solutions in single and binary systems. Surface characteristics of CR were investigated using Fourier transform infrared (FTIR), x-ray diffraction, and scanning electron microscopy. Effects of CR dosage and contact time were investigated at 30°C. Kinetic and isotherm aspects of heavy metal adsorption were studied. Adsorption kinetics of heavy metals were studied in single and binary systems and rate sorption was found to conform to a pseudo second-order kinetic model. Intraparticle diffusion plots showed that the adsorption processes involve multistep kinetic stages. Isotherm aspects of heavy metals in single and binary systems followed the Freundlich isotherm. Maximum adsorption capacity of CR for Cu and Zn was 500 mg/g and 208 mg/g for the single system. Results indicated that CR is effective for adsorption of Cu and Zn from aqueous solutions.

Highly efficient removal of hexavalent chromium from electroplating wastewater using aminated wheat straw

“…Electroplating wastewater contains high concentrations of heavy metals and has attracted great attention for many years in terms of environmental impact and removal techniques. [1][2][3] Some toxic metallic ions such as chromate have signicant impacts on human health and other living organisms in aquatic environments if they are discharged into surface waters. 4,5 Commonly, chromium exists as trivalent chromium (Cr(III)) and hexavalent chromium (Cr(VI)) in electroplating wastewater.…”

Invasive plants as biosorbents for environmental remediation: a review

“…Using invasive plants as bioremediators for the removal of copper may be one of the efficient solutions. Ramesh et al (2013) reported the very high maximum copper adsorption capacity (up to 500 mg/g at 30 °C) obtained by Cyperus rotundus biosorbent. In this study, they found the optimum dose of biosorbent and equilibrium time was 1.0 g/L, and 30 min, respectively.…”

Uso de residuos de café como biosorbente para la remoción de metales pesados en aguas residuales

“…Cuando la dosis o cantidad adicionada del material absorbente es alta se alcanza una velocidad de adsorción rápida, debido a que hay más sitios disponibles en la superficie para retener metales [28,29]. Arief et al aseveran que al incrementar la dosificación del adsorbente la eficiencia aumenta, aunque la cantidad adsorbida por unidad de masa disminuye.…”