Kinetic, isotherm and thermodynamic studies on biosorption of chromium(VI) by using activated carbon from leaves of Ficus nitida.

Ismat H Ali,H A Alrafai

doi:10.1186/s13065-016-0180-1

Abstract

BackgroundKinetics, thermodynamics and equilibrium of the removal of chromium(VI) ions from aqueous solutions by using chemically activated leaves of Ficus nitida were investigated. Adsorption runs were performed as a function of pH, mass of biosorbent, contact time, initial concentration of chromium(VI) ions and temperature.ResultsThe optimum conditions for maximum removal of chromium(VI) ion from aqueous solutions (about 99 %) were found to be 0.80 g of chemically activated leaves of F. nitida, 25 min, 50.0 mg/L of initial concentration of chromium(VI). Values of thermodynamic activation parameters proved that the biosorption process is spontaneous and endothermic. Results were analyzed by using Langmuir, Freundlich and Temkin models.ConclusionsResults of the study showed that the chemically activated leaves of F. nitida can be used as low cost, ecofriendly and effective sorbent for the removal of chromium(VI) from aqueous solutions.Graphical abstractFicus nitida is an efficient bio-sorbent used for removal of Cr(VI) ion

Highlights

Kinetics, thermodynamics and equilibrium of the removal of chromium(VI) ions from aqueous solutions by using chemically activated leaves of Ficus nitida were investigated
Reliability of results A number of parameters i.e., linearity, limit of detection (LOD), limit of quantitation (LOQ), relative standard deviation (RSD) were determined in order to check the reliability of results
LOD and LOQ Sensitivity was evaluated by determination of limit of detection (LOD) and limit of quantitation (LOQ). (LOD) and (LOQ), were determined by measuring 10 blank samples

Summary

Introduction

Thermodynamics and equilibrium of the removal of chromium(VI) ions from aqueous solutions by using chemically activated leaves of Ficus nitida were investigated. Adsorption runs were performed as a function of pH, mass of biosorbent, contact time, initial concentration of chromium(VI) ions and temperature. In the recent years the activities of industrial sectors has showed a considerable spread and development, but concurrently the natural environment has been contaminated. Heavy metals are one of the most widespread pollutants which contaminate the environment and cause serious damage to the ecosystem and may be a reason for various dangerous diseases suffered by animals and human beings [1]. A number of industries are causing heavy metal pollution e.g. battery manufacturing processes, mining and metallurgical engineering, dyeing operations, electroplating, nuclear power plants, tanning, production of paints and pigments [2]. Chromium(VI) is one of the most poisonous contaminants which cause severe diseases and very harmful environmental complications. Strong exposure to chromium(VI) has been linked to various types of cancer and may cause epigastric pain, nausea, vomiting, severe diarrhea and hemorrhage [5]

Objectives

Results

Conclusion