Uncovering the Multiple Adsorption Mechanisms of Heavy Metals by Eggshells

YAIR AMAR, Analytical chemistry, NRCN, ntivot, israel (yairam77@gmail.com)

Recently, there has been a growing interest in cheap and effective materials for heavy metals and organic compounds adsorption ^[1-2], focusing on waste materials from industrial, agricultural and domestic sources. Such materials have great potential as sustainable solutions for wastewater treatment, while simultaneously contributing to waste minimization. Examples of cheap adsorbents include rice husks, corn cobs, bird feathers, cotton, and sawdust. Ideally, the adsorbent material only requires minimal pre-processing and adjustments prior to use.

Eggshells are a common waste material, which is difficult to dispose of. Consequently, there has been much interest in the use of eggshells as adsorbents. Many studies report the efficiency and optimal conditions for organic and inorganic pollutant adsorption using eggshells and eggshell membranes. Examples of pollutants documented in the literature include fluoride, actinides, dyes and various toxic metals (lead, chromium, cadmium, copper, arsenic, manganese, nickel and mercury)^[3]

Our research focuses on uncovering the various adsorption mechanisms of the eggshells. A better understanding of the adsorption mechanism will lead to a more efficient use of eggshells for adsorption applications. We will present preliminary results for the eggshell adsorption capacity of seven toxic metals and suggestions for the various adsorption mechanisms of the metals to the eggshells.

Reference

[1] – Alternative Low-cost Adsorbent for Water and Wastewater Decontamination Derived from Eggshell Waste, An Overrview. F.Castro et al. Waste and biomass valorizatio 2 157-167 (2011)

[2] -   Characteristics and adsorption capacities of low-cost sorbents for wastewater treatment; A review. M.Notarnicola et al. Sustainable Materials and Technologies 9 10-40 (2016)

[3] – Applications of eggshell and egg shell membrane as adsorbents: A review

A. Mittal, M. Teotia, R.K. Soni, J. Mittal. Journal of molecular liquids 222 276-288 (2016)