Adsorption Studies of Textile Dye (Chrysoidine) from Aqueous Solutions Using Activated Sawdust

Muhammad Waqar Ashraf,Abdus Salam,Nidal Abulibdeh

doi:10.1155/2019/9728156

Abstract

Chrysoidine is a type of industrial azo dye and a well-known toxicant. Due to its good dyeing characteristics, it is widely used for dyeing leather, paper, feather, grass, wood, bamboo, etc. Hence, it is very important to remove or reduce its concentration below the contamination level in the waste line by using low-cost technologies. Sawdust is a plentiful material available very cheaply from sawmills and woodworks. Therefore, the present work was conducted to study sorption ability of both raw sawdust and chemically activated sawdust carbon on the removal of chrysoidine from the aqueous solutions. Adsorption isotherms of the dye on sawdust were determined and correlated with usual isotherm equations like Freundlich and Langmuir. Experimental results have shown that sawdust has a high adsorption efficiency, and the adsorption of chrysoidine followed Freundlich’s isotherm. Although raw sawdust proved to be slightly less efficient in comparison to chemically treated sawdust but in economic terms, raw sawdust is more cost-effective as the difference in the percent dye removal is less than the difference in the manufacturing costs. The influence of several parameters such as effect of temperature, adsorbent dose, adsorption time, etc., on the adsorption process was studied along with thermodynamic parameters such as enthalpy (ΔH°) and entropy (ΔS°).

Highlights

Wastewaters from textile industries are colored, which is mainly due to dyes used in textile industry
One part was chemically treated, while the second was kept for use in its raw form. e first part was treated with sulphuric acid in the ratio of 4 : 3 parts by weight. e material was kept in a vacuum oven for 24 hours at 150°C. e carbonized material was washed thrice with distilled water to remove any unreacted acid and dried at 100°C for 24 hours. e material was finely grounded and passed through sieve ISS 600 and stored. is material was used in adsorption experiments as chemically activated sawdust. e second part of the sawdust was saturated with the distilled water and washed repeatedly to remove the typical yellow color of the sawdust caused by lignin
It can be deduced that for any particular experiment, the rate of adsorption decreased with time until it gradually approached a plateau owing to the continuous decrease in the driving force and indicating that the adsorbent is saturated at this point

Summary

Introduction

Wastewaters from textile industries are colored, which is mainly due to dyes used in textile industry. Chemical species present in textile effluents are of diverse nature, posing a challenge to conventional physicochemical and biological treatment methods. Dyes are almost invariably toxic, and a visible pollutant, so their removal from the effluent stream is ecologically essential. Recent estimates indicate that approximately 12% of synthetic dyes used each year are lost during manufacture and processing operations and that 20–35% of these input dyes enter the environment through effluents from the treatment of residual industrial water. Dyes are visible even in extremely diluted forms, posing aesthetic problems, and are toxic to human and aquatic life [1,2,3,4,5]

Methods

Results

Conclusion