A potential low cost adsorbent for the removal of cationic dyes from aqueous solutions

Md Tamez Uddin,Md Rukanuzzaman,Md Arifur Rahman,Md Akhtarul Islam

doi:10.1007/s13201-017-0542-4

Md Tamez Uddin, Md Rukanuzzaman + Show 2 more

Open Access

https://doi.org/10.1007/s13201-017-0542-4

Copy DOI

Abstract

This study was aimed at using mango leaf powder (MLP) as a potential adsorbent for the removal of methylene blue (MB) from aqueous solutions. Characterization of the adsorbent was carried out with scanning electron microscopy, Fourier transform infrared spectroscopy, and nitrogen adsorption–desorption analysis. The pH at the point of zero charge of the adsorbent was determined by titration method and was found a value to be 5.6 ± 0.2. Batch studies were performed to evaluate the influence of various experimental parameters like initial solution pH, contact time, initial concentration of dye and adsorbent dosage on the removal of MB. An adsorption–desorption study was carried out resulting the mechanism of adsorption was carried out by electrostatic force of attraction. The adsorption equilibrium time required for the adsorption of MB on MLP was almost 2 h and 85 ± 5% of the total amount of dye uptake was found to occur in the first rapid phase (30 min). The Langmuir and Freundlich isotherm models were used for modeling the adsorption equilibrium. The experimental equilibrium data could be well interpreted by Langmuir isotherm with maximum adsorption capacity of 156 mg/g. To state the sorption kinetics, the fits of pseudo-first-order and pseudo-second-order kinetic models were investigated. It was obtained that the adsorption process followed the pseudo-second-order rate kinetics. The above findings suggest that MLP can be effectively used for decontamination of dye containing wastewater.

Highlights

Many industries, such as textiles, cosmetics, leather, pulp mills, printing, dye synthesis, foods and plastics industries widely use dyes as coloring agents
The adsorption equilibrium time required for the adsorption of methylene blue (MB) on mango leaf powder (MLP) was almost 2 h and 85 ± 5% of the total amount of dye uptake was found to occur in the first rapid phase (30 min)
The Fourier transform infrared (FTIR) analysis indicated that the MLP contained functional groups such as OH and COOH that could be potential adsorption sites for interaction with the cationic MB dye

Summary

Introduction

Many industries, such as textiles, cosmetics, leather, pulp mills, printing, dye synthesis, foods and plastics industries widely use dyes as coloring agents. Methylene blue is a basic dye of thiazine group and is known as swiss blue and tetramethyl thionine. It appears as a dark green powder that yields a blue solution when dissolved in water. It can cause some harmful effects in humans such as heartbeat increase, vomiting, shock, cyanosis, jaundice, quadriplegia, and tissue necrosis. Their removal from industrial effluents before discharging into the environment is extremely important

Objectives

Methods

Results

Conclusion