Adsorption of Cadmium (II) and Chromium (VI) from Aqueous Solution by Waste Marigold Flowers

Monoj Kumar Mondal,Garima Mishra,Pradeep Kumar

doi:10.13044/j.sdewes.2015.03.0030

Monoj Kumar Mondal, Garima Mishra + Show 1 more

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https://doi.org/10.13044/j.sdewes.2015.03.0030

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Abstract

In this work, waste marigold flowers from Temple were used as adsorbent to remove cadmium (II) and chromium (VI) ions from aqueous solutions. Influences of initial heavy metal concentrations, contact time, adsorbent dose, temperature and initial pH on removal of cadmium (II) and chromium (VI) ions were studied under batch mode of operation. Both the adsorption process of cadmium (II) and chromium (VI) followed pseudo-second order kinetics. Adsorption isotherm parameters of cadmium (II) and chromium (VI) on dried marigold flower were determined using Langmuir and Freundlich models. Thermodynamic parameters depicted that the process was spontaneous and exothermic under experimental conditions. The maximum removal efficiency of cadmium (II) was obtained as 83% at contact time 75 min and pH 5. The maximum removal efficiency of chromium (VI) was found as 96% at contact time 105 min and pH 3. Dried marigold flower showed active reusability characteristics upto three consecutive adsorption-desorption cycles.

Highlights

Heavy metal contamination of water through the discharge of industrial wastewater is a growing environmental issue worldwide
Characterization of the adsorbent To understand the mechanism of adsorption of heavy metal onto adsorbent, it is necessary to determine point of zero charge of the adsorbent
X-Ray Diffraction (XRD) study of dried marigold flower was performed by powder diffractometer (Rigaku, Japan) fitted with a curved crystal monochromator in the diffracted beam operating at 40 kV and 150 mA

Summary

INTRODUCTION

Heavy metal contamination of water through the discharge of industrial wastewater is a growing environmental issue worldwide. The most common heavy metal contaminating industries are metal plating, mining operations, battery manufacturing, paints and pigments, ammunition, ceramic and glass industries. The wastewater from these industries commonly contain toxic heavy metals like Cd (II), Pb (II), Cu (II), Ni (II), and Cr (VI) [1]. Industrialization moves so rapid that the discharge of heavy metals into the environment increases [2]. Numbers of treatment methods like ion exchange [3], precipitation, filtration, oxidation-reduction, membrane separation, and adsorption [3, 4] are known for separation and removal of metallic species from aqueous solutions and wastewaters. It has been reported that application of these methods is limited due to high operational costs or insufficient removal efficiencies to meet the

MATERIALS AND METHODS

RESULTS AND DISCUSSION

CONCLUSIONS