Fast and effective arsenic removal from aqueous solutions by a novel low-cost eggshell byproduct

Ivan Célio Andrade Ribeiro; Isabela Cristina Filardi Vasques; Jéssica Cristina Teodoro; Marcelo Braga Bueno Guerra; Jefferson Santana da Silva Carneiro; Leônidas Carrijo Azevedo Melo; Luiz Roberto Guimarães Guilherme

doi:10.1016/j.scitotenv.2021.147022

Fast and effective arsenic removal from aqueous solutions by a novel low-cost eggshell byproduct

Sci Total Environ. 2021 Aug 20:783:147022. doi: 10.1016/j.scitotenv.2021.147022. Epub 2021 Apr 20.

Authors

Ivan Célio Andrade Ribeiro¹, Isabela Cristina Filardi Vasques², Jéssica Cristina Teodoro³, Marcelo Braga Bueno Guerra⁴, Jefferson Santana da Silva Carneiro¹, Leônidas Carrijo Azevedo Melo¹, Luiz Roberto Guimarães Guilherme⁵

Affiliations

¹ Department of Soil Science, Federal University of Lavras, Lavras, Minas Gerais 37200-900, Brazil.
² Department of Soils, Federal University of Viçosa, Viçosa, Minas Gerais 36570-900, Brazil.
³ Department of Biology, Federal University of Lavras, Lavras, Minas Gerais 37200-900, Brazil.
⁴ Department of Chemistry, Federal University of Lavras, Lavras, Minas Gerais 37200-900, Brazil.
⁵ Department of Soil Science, Federal University of Lavras, Lavras, Minas Gerais 37200-900, Brazil. Electronic address: guilherm@ufla.br.

PMID: 34088149
DOI: 10.1016/j.scitotenv.2021.147022

Abstract

Developing alternative green solutions for local and correct recycling of eggshells waste (ES) are needed by the egg-processing industries. In this study, we proposed transforming ES into a novel low-cost chemical compound named hydroxyl-eggshell (ES-OH) and investigated its capacity for arsenic (As) removal from aqueous solutions. Laboratory experiments were conducted to investigate the effects of ES-OH doses, pH, kinetics, and isotherms on As removal efficiency. The kinetics study showed that ES-OH removed nearly all As from solution in less than 15 min. The pseudo-second-order model described the process, and the maximum As removal capacity predicted by the Langmuir isotherm model was 529 mg g^-1. Using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy with energy dispersive X-ray detector (SEM-EDS), and X-ray diffraction (XRD), we found that the As removal mechanism by ES-OH was due to vladimirite precipitation, followed by weak electrostatic interactions between the precipitate and arsenate ions. Finally, after an economic analysis, we conclude that besides being a novel and economical income source, egg-producing companies might implement the ES-OH production process as a local environmentally-friendly way of recycling eggshells and reducing water As contamination.

Keywords: Calcium arsenate; Circular economy; Vladimirite; Waste valorization.