Loofa egyptiaca as a novel adsorbent for removal of direct blue dye from aqueous solution

• Published in: Journal of environmental management Vol. 90; no. 8; pp. 2755 - 2761
• Main Author: El Ashtoukhy, El Sayed Z.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.06.2009; Elsevier; Academic Press Ltd
• Subjects: Activated carbon; Adsorbents; Adsorption; Adsorption isotherm; Animal, plant and microbial ecology; Applied ecology; Aqueous solutions; Biological and medical sciences; cellulosic fibers; Charcoal - chemistry; Charcoal - metabolism; Coloring Agents - chemistry; Coloring Agents - isolation & purification; Conservation, protection and management of environment and wildlife; Cost analysis; Direct dye; Dyes; Egypt; Experiments; Flora; Flowers & plants; Fundamental and applied biological sciences. Psychology; General aspects; Innovation; Isotherms; Kinetics; Loofa; Loofa egyptiaca; Loofas; Luffa - chemistry; plant fibers; Scanning electron microscopy; sorption isotherms; Surface chemistry; Waste management; wastewater treatment; Water Purification - methods; Direct dye; Kinetics; Loofa; Activated carbon; Adsorption isotherm; Dyes; Aqueous solution; Adsorbent; Environmental management
• ISSN: 0301-4797; 1095-8630
• DOI: 10.1016/j.jenvman.2009.03.005

In this paper, Loofa egyptiaca (LE), an agricultural plant cultivated in Egypt, was used to prepare low-cost activated carbon (LE C1 and LE C2) adsorbents. The adsorbents (LE, LE C1 and LE C2) were evaluated for their ability to remove direct blue 106 dye from aqueous solutions. Batch mode experiments were conducted using various parameters such as pH, contact time, dye concentration and adsorbent concentration. The surface chemistry of LE, LE C1 and LE C2 was analyzed by scanning electron microscopy (SEM). The experimental data were examined using Langmuir, Freundlich, Temkin and Harkins–Jura isotherms. The results showed that the adsorption of direct blue 106 was maximal at the lowest value of pH (pH = 2). Removal efficiency was increased with an increase in dye concentration and a decrease in amount of adsorbent. Maximum adsorption capacity was found to be 57.14, 63.3 and 73.53 mg/g for LE, LE C1 and LE C2 respectively. Kinetics were also investigated using pseudo-first-order, pseudo-second-order and intra-particle diffusion models. The experimental data fitted very well with the pseudo-first-order and pseudo-second-order kinetic models. The results indicate that LE, LE C1 and LE C2 could be employed as adsorbents for the removal of direct blue dye from aqueous solutions.