Biosorption of methyl blue onto tartaric acid modified wheat bran from aqueous solution

Shuhua Yao,Hong Lai,Zhongliang Shi

doi:10.1186/1735-2746-9-16

Abstract

Tartaric acid modified wheat bran was utilized as adsorbent to remove methyl blue, a basic dye from aqueous solution. Batch experiments were carried out to study the effect of various experimental parameters such as initial solution pH, contact time, initial dye concentration and adsorbent dosage, on dye adsorption. The results showed that the modification of wheat bran by tartaric acid significantly improved its adsorption capacity, and made this material a suitable adsorbent to remove methyl blue. The adsorption capacity of modified wheat bran was about 1.6 times higher than that of unmodified one. The amount of methyl blue adsorbed was found to vary with initial solution pH, adsorbent dosage, contact time and initial methyl blue concentration. Kinetics study showed that the overall adsorption rate of methyl blue was illustrated by pseudo-second-order kinetic model. The applicability of the Langmuir and Freundlich models for the data was tested. Both models adequately described the experimental data of the biosorption of methyl blue. The maximum adsorption capacity for methyl blue calculated from Langmuir model was 25.18 mg/g. The study has shown the effectiveness of modified wheat bran in the removal of methyl blue, and that it can be considered as an attractive alternative to the more expensive technologies used in wastewater treatment.

Highlights

Improper dye discharge from various industries such as textile, paper, cosmetic and plastics into receiving streams can be one of the sources of water pollution
The purpose of the present study was to a) investigate the adsorption of the cationic dye methylene blue (MB) on to wheat bran modified with tartaric acid bran; b) study the effect of different parameters such as contact time, initial pH, adsorbent dosage and initial MB concentration on adsorption process and; c) find optimum adsorption isotherm as well as the rate of adsorption kinetics
Comparison of the results on the uptake of MB by unmodified and modified wheat bran showed that the removal rates of MB was 55.32% and 85.76%, respectively

Summary

Introduction

Improper dye discharge from various industries such as textile, paper, cosmetic and plastics into receiving streams can be one of the sources of water pollution. There has been intensive research exploring the potential of alternative low-cost materials as sorbents for dyes For this purpose in recent years, various biological and industrial by-products have been investigated intensively for their ability to remove dye from aqueous solution, as they can be obtained readily and are in great abundance, such as corncob [5], chitosan [6], waste coir pith [7], giant duckweed [8], powdered peanut hull [9], coccinea berries [10], trees’ leaves [11], eggshell [12], modified clays [13], fly ash [14], beer brewery waste [15], natural zeolite [16], bentonite [17], rice bran [18] and rice hull [19]. Some biosorbents have shown extraordinary properties for dye removal

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Discussion

Conclusion