Application of Agro‐Based Biomasses for Zinc Removal from Wastewater – A Review

Abstract

Zinc remediation of aqueous streams is of special concern due to its highly toxic and persistent nature. Conventional treatment technologies for the removal of zinc are not economical and further generate huge quantity of toxic chemical sludge. Biosorption is emerging as a potential alternative to the existing conventional technologies for the removal of metal ions from aqueous solutions. Mechanisms involved in the biosorption process include chemisorption, complexation, adsorption-complexation on surface and pores, ion exchange, microprecipitation, heavy metal hydroxide condensation onto the bio surface, and surface adsorption. Biosorption largely depends on parameters such as pH, the initial metal ion concentration, biomass concentration, presence of various competitive metal ions in solution, and to a limited extent on temperature. Biosorption using biomass such as agricultural wastes, industrial residues, municipal solid waste, biosolids, food processing waste, aquatic plants, animal wastes, etc., is regarded as a cost-effective technique for the treatment of high volume and low concentration complex wastewaters containing zinc metal. Very few reviews are available where readers can get an overview of the sorption capacities of agro based biomasses used for zinc remediation together with the traditional remediation methods. The purpose of this review article is to provide the scattered available information on various aspects of utilization of the agro based biomasses for zinc metal ions removal. An extensive table summarizes the sorption capacities of various adsorbents. These biosorbents can be modified using various methods for better efficiency and multiple reuses to enhance their applicability at industrial scale. We have incorporated most of the valuable available literature on zinc removal from waste water using agro based biomasses in this review.

Cadmium Removal from Aqueous Solutions Using Dried Banana Peels as An Adsorbent: Kinetics and Equilibrium Modeling

“…Working solutions of concentrations 1,5,10,15,20,25,30,40, 50 ppm were prepared by using appropriate amount of stock cadmium solution.…”

“…These functional groups bind metal through ion exchange by transferring hydrogen ions or through complex formation by sharing electron pair [15]. Most of these agricultural materials showed significant adsorption capacities than Granular Activated Carbon [13].…”

Enhanced Absorbent Products Incorporating Cellulose and Its Derivatives: A Review

“…10, addition of NaCl to the material is expected to result in weakening of the complex such that the salt ions behave as counter-ions to the charged polyelectrolyte chains. The effectiveness of the PEC-type hydrogels to enable the removal of NaCl from solution is notable because most reported applications of cellulosic-based materials for ion exchange have involved removal of divalent metal ions (Rudie et al 2006;Hubbe et al 2011;Kumar et al 2011). In such applications it is typical for the divalent ions to displace monovalent ions within the substrate due to their greater binding constants.…”

Optimization and equilibrium studies of Pb(II) removal by Grewia Asiatica seed: a factorial design approach

“…It is reported that the use of untreated biomass as the biosorbent can lead to high chemical oxygen demand (COD) due to the release of soluble organic compounds contained in these materials. Also these materials discharge color in the treated water 17 . We found that Grewia asiatica fruit seed did not release any color into the system at any pH (acidic, neutral or basic), hence can be used without any treatment.…”