Use of Hydrous Manganese Oxides Nanopowders as a Potential Sorbent for Selective Removal of Nickel Ions from Industrial Waste Water, Kinetics and Isotherm Studies

R. Ghaniem

doi:10.11648/j.ajche.20160406.15

Abstract

Hydrous Manganese Oxides Nanopowders as nano adsorbent (MONs) was synthesized and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transform infrared spectroscopy (FT-IR). The adsorption of Ni (II) ions from aqueous solution on the MONs was investigated with variations in contact time, pH, initial Ni (II) concentration and adsorbent dosage. The results showed that the adsorption of Ni (II) onto MONs increased within 25 min and reached equilibrium gradually and removal percentage were 83%, 57%, 42% and 35% for 25 ppm, 50 ppm, 75 ppm and 100 ppm Ni (II), respectively, by using 1g/l MONs for 90 min at pH 6. The adsorption behavior of Ni (II) onto MONs was best described by the pseudo-second-order model and Freundlish isotherm. The results also indicated that the type of adsorption involved in this study is physiosorption (physical sorption) which usually takes place at low temperature. The results also revealed that MONs was a promising adsorbent for removal of Ni ions from industrial wastewater.

Highlights

Water contamination with toxic heavy metals from the industrial wastewater activities have become a serious environmental and public health problem
If the plot of qt versus t0.5 gives a straight line passing through the origin, the adsorption process is only controlled by intra-particle diffusion, if multi-linearity in qt vs. t1/2 plot is considered Figure 7 shows that the external surface adsorption occurs in the first step; the second step is the gradual adsorption step, where intraparticle diffusion is controlled; and the third step is the final equilibrium step, where the solute moves slowly from larger pores to micropores causing a slow adsorption rate
The results showed that the maximum adsorption capacities of Ni (II) onto Manganese Oxides Nanopowders as nano adsorbent (MONs) were 35 mg/g

Summary

Introduction

Water contamination with toxic heavy metals from the industrial wastewater activities have become a serious environmental and public health problem. With the rapid increase of global industrial activities, heavy metal pollution on water resources is considered a hazardous effect on human beings [1,2,3]. Heavy metals found their ways to the environment through wastewater streams of the modern industrial activities such as batteries, pesticides, fertilizer and paper industries, metal plating, and mining operations [4,5]. Many treatment methods have been reported in the literatures which can be used to remove heavy metals from aqueous solutions. Among these methods are; the chemical precipitation, ion exchange, coagulation and electrochemical removal, but these methods led to high-energy requirements, and production of toxic sludge [7]

Methods

Results

Conclusion