Adsorptive removal of dyes from aqueous solution onto carbon nanotubes: A review

• Published in: Advances in colloid and interface science Vol. 193-194; pp. 24 - 34
• Main Authors: Gupta, Vinod Kumar, Kumar, Rajeev, Nayak, Arunima, Saleh, Tawfik A., Barakat, M.A.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.06.2013; Elsevier
• Subjects: Active sites; Adsorbents; Adsorption; Aqueous solutions; Carbon nanotubes; Chemistry; Coloring Agents - chemistry; Coloring Agents - isolation & purification; cost effectiveness; Desorption; Dyes; Exact sciences and technology; Gas-liquid interface and liquid-liquid interface; General and physical chemistry; Hydrogen-Ion Concentration; hydrophobicity; Nanostructure; Nanotubes, Carbon - chemistry; pollutants; Single wall carbon nanotubes; surface area; Surface chemistry; Surface physical chemistry; Temperature; Waste water; wastewater; Water - chemistry; Water Pollutants, Chemical - chemistry; Water Pollutants, Chemical - isolation & purification; Carbon nanotubes; Desorption; Dyes; Active sites; Adsorption; Organic dye; Multiwalled nanotube; Liquid solid adsorption; Organic adsorbate; Review; Aqueous solution; Adsorbent
• ISSN: 0001-8686; 1873-3727; 1873-3727
• DOI: 10.1016/j.cis.2013.03.003

Adsorption is a widely used technique for the separation and removal of pollutants from wastewaters. Carbon nanotubes (CNTs) are emerging as potential adsorbents because of its well defined cylindrical hollow structure, large surface area, high aspect ratios, hydrophobic wall and easily modified surfaces. In this review, dye adsorption capability of CNTs and CNT based composites from aqueous system has been compiled. This article provides the information about the defect, adsorption sites on CNTs and batch adsorption studies under the influence of various operational parameters such as contact time, solution pH, temperatures etc. and deals with mechanisms involved in adsorption of dyes onto CNTs. From the literature reviewed, it is observed that single walled carbon nanotubes (SWCNTs) show higher adsorption capacity than multi walled carbon nanotubes (MWCNTs) and functionalized and CNT composite have better sorption capacity than as grown CNTs. It is evident from the literature that CNT based nanosorbents have shown good potential for the removal of dyes from aqueous solution. However, still more research work should be focused on the development of cost effective, higher efficient and environmental friendly CNT based nanosorbents for their commercial applications. [Display omitted] •Adsorption of dyes onto CNTS and CNT based composite adsorbents has been reviewed.•Adsorption of dyes onto CNTS is highly dependent on solution pH, concentration and temperature.•The sorption capacities of MWCNTs for dyes are lower than SWCNTs.•π–π interaction and electrostatic interactions are mainly involved in the adsorption.