A review on applicability of naturally available adsorbents for the removal of hazardous dyes from aqueous waste

Abstract

The effluent water of many industries, such as textiles, leather, paper, printing, cosmetics, etc., contains large amount of hazardous dyes. There is huge number of treatment processes as well as adsorbent which are available for the processing of this effluent water-containing dye content. The applicability of naturally available low cast and eco-friendly adsorbents, for the removal of hazardous dyes from aqueous waste by adsorption treatment, has been reviewed. In this review paper, we have provided a compiled list of low-cost, easily available, safe to handle, and easy-to-dispose-off adsorbents. These adsorbents have been classified into five different categories on the basis of their state of availability: (1) waste materials from agriculture and industry, (2) fruit waste, (3) plant waste, (4) natural inorganic materials, and (5) bioadsorbents. Some of the treated adsorbents have shown good adsorption capacities for methylene blue, congo red, crystal violet, rhodamine B, basic red, etc., but this adsorption process is highly pH dependent, and the pH of the medium plays an important role in the treatment process. Thus, in this review paper, we have made some efforts to discuss the role of pH in the treatment of wastewater.

Adsorptive Removal of Methylene Blue from Aqueous Solution by Spent Mushroom Substrate: Equilibrium, Kinetics, and Thermodynamics

“…Dyes are widely used in many industries, such as textiles, leather, cosmetics, paper, and printing plastics (Sharma et al 2011). More than 10×10 5 commercially available dyes with over 7×10 5 tons of dyestuff are produced per year (Pearce 2003), and about 10 to 15% of the used dye is lost in the effluent of textile units (Dod et al 2012;Husain 2006).…”

Effects of Bentonite Activation Methods on Chitosan Loading Capacity

“…The loading of chitosan on bentonite was examined using various reaction times (10-90 min), initial chitosan concentrations (250-2500 mg/L), stirring speeds (50-300 rpm), temperatures (30-50 °C), and pH values (2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12). Specifically, 1 g of raw bentonite clay was dispersed in 150 mL of distilled water.…”

“…Natural bentonite clays are often used to adsorb metallic contaminants, since they are low-cost, abundant materials that have excellent cation exchange capacity and relatively large surface areas [3,4]. Chitosan modification of bentonite clay improves its effectiveness in water treatments, by mitigating certain flaws of bentonite clays, including high swelling and suspendability, difficult separation [5,6].…”

Removal of dexamethasone from aqueous solutions using modified clinoptilolite zeolite (equilibrium and kinetic)

“…Among the common processes for purification, the removals of contaminants through using the adsorption technology on natural materials have gained much interest during recent decades (Elwakeel and Guibal, 2015a, b;Sharma et al 2011;Amuda and Ibrahim, 2006). In the adsorption mechanism, attractive forces play the main role between adsorbent and adsorbate functional groups.…”