Modification of waste wool fiber as low cost adsorbent for the removal of methylene blue from aqueous solution

Abstract

REMOVAL of methylene blue (MB) from water using adsorbent developed from waste wool fiber has been investigated by batch adsorption experiments in the present work. Wool fiber waste (WF) was collected from a local Spinning and Weaving Company, cleaned and further treated with citric acid to increase its adsorption capacity toward basic dyes. Raw and treated WF were ball milled to produce wool powder (WP) and modified wool powder (MWP), respectively. The carboxyl content was increased steadily as the citric acid solution concentration increased. The introduction of the carboxyl groups also has been proved by streaming potential measurements. The effect of contact time, wool dose and dye solution pH on the adsorption process were studied too. The adsorption isotherm was examined using Langmuir, Freundlich, and Dubinin-Radushkevich (D-R) models. The adsorption equilibrium was attained within 20 minutes with a maximum removal percentage of 70 and 78 for WP and MWP, respectively. The wool dose affects the adsorption process significantly, especially for MWP which removes a higher percentage of MB (86 %) compared to WP (75 %). Both Freundlich and D-R were well fitting the adsorption equilibrium data with R 2 > 0.9. The values of Freundlich exponent factor (n) and D-R adsorption energy (E) reveal the chemisorption nature of the MB adsorption on both WP and MWP. This work demonstrated that, chemical and physical modifications of the waste wool fiber with citric acid has enhanced the adsorption of MB.

Fabrication, characterization, and dye adsorption capability of recycled modified polyamide nanofibers

“…Consequently, MB might form a multilayer on the PA-nanofiber surface. In addition, it is known that the value of n indicates the favorability and the nature of adsorption process [47]. In this study the n value is higher than unity thus the adsorption is favorable and might be chemisorption process.…”

“…Figure 5a shows that the amount of MB removed increases monotonously with increasing the nanofiber mat dosage reaching 23% and 90% for PA-nanofiber and modified PAnanofiber, respectively, when the applied dosage was 1g/L. This trend is owing to increasing both the surface area and adsorption sites with the nanofiber mat dosage [45][46][47]. Contrary, the q e dramatically decreased with increasing the nanofiber mat dosage (Fig.…”

“…Consequently, MB are electrostatically attracted to the nanofiber mat resulting in higher R%. In addition, the negative charges on the nanofiber mat surface repel each other causing expansion of the network and consequently increasing the MB removal [27,46,47].…”

Phenomena of Removal of Crystal Violet from Wastewater Using Khulays Natural Bentonite

“…e increase of the site negative charge on the clay increases the cationic dye adsorption, which results due to increased electrostatic attraction. Previous studies have established that the increase in the solution pH improves the sorption of the cationic dye at an increasing pH level [24].…”

Evaluation of Synthesized Ozone by Dielectric Barrier Discharge Plasma for Degradation of Anionic Dyes from their Solutions

“…This colored waste water has a great bad effect on aesthetic merit, the purity and transparency of water that body needs and receives. [1][2][3][4] In addition, it is against the environment and causes many concerns about the possible toxicity and carcinogenicity of some organic dyes. Treatment of textile dyes house effluent is necessary because of its inherent color, which is unacceptable to environmental regulatory agencies and aesthetically unpleasant.…”