Enhanced selective metal adsorption on optimised agroforestry waste mixtures

Emilio Rosales; Laura Ferreira; M Ángeles Sanromán; Teresa Tavares; Marta Pazos

doi:10.1016/j.biortech.2015.01.094

Enhanced selective metal adsorption on optimised agroforestry waste mixtures

Bioresour Technol. 2015 Apr:182:41-49. doi: 10.1016/j.biortech.2015.01.094. Epub 2015 Jan 31.

Authors

Emilio Rosales¹, Laura Ferreira², M Ángeles Sanromán³, Teresa Tavares⁴, Marta Pazos⁵

Affiliations

¹ Department of Chemical Engineering, University of Vigo, Isaac Newton Building, Campus As Lagoas Marcosende, 36310 Vigo, Spain; Centro de Engenharia Biológica, Universidade do Minho, Campus de Gualtar, 4710-057 Braga, Portugal. Electronic address: emiliorv@uvigo.es.
² Department of Chemical Engineering, University of Vigo, Isaac Newton Building, Campus As Lagoas Marcosende, 36310 Vigo, Spain. Electronic address: ferreira@uvigo.es.
³ Department of Chemical Engineering, University of Vigo, Isaac Newton Building, Campus As Lagoas Marcosende, 36310 Vigo, Spain. Electronic address: sanroman@uvigo.es.
⁴ Centro de Engenharia Biológica, Universidade do Minho, Campus de Gualtar, 4710-057 Braga, Portugal. Electronic address: ttavares@deb.uminho.pt.
⁵ Department of Chemical Engineering, University of Vigo, Isaac Newton Building, Campus As Lagoas Marcosende, 36310 Vigo, Spain. Electronic address: mcurras@uvigo.es.

PMID: 25681794
DOI: 10.1016/j.biortech.2015.01.094

Abstract

The aim of this work is to ascertain the potentials of different agroforestry wastes to be used as biosorbents in the removal of a mixture of heavy metals. Fern (FE), rice husk (RI) and oak leaves (OA) presented the best removal percentages for Cu(II) and Ni(II), Mn(II) and Zn(II) and Cr(VI), respectively. The performance of a mixture of these three biosorbents was evaluated, and an improvement of 10% in the overall removal was obtained (19.25mg/g). The optimum mixture proportions were determined using simplex-centroid mixture design method (FE:OA:RI=50:13.7:36.3). The adsorption kinetics and isotherms of the optimised mixture were fit by the pseudo-first order kinetic model and Langmuir isotherm. The adsorption mechanism was studied, and the effects of the carboxylic, hydroxyl and phenolic groups on metal-biomass binding were demonstrated. Finally, the recoveries of the metals using biomass were investigated, and cationic metal recoveries of 100% were achieved when acidic solutions were used.

Keywords: Agroforestry wastes; Biosorption; Multi-metals; Simplex-centroid mixture design.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Adsorption
Agriculture
Biomass
Forestry
Industrial Waste*
Kinetics
Metals, Heavy / chemistry
Metals, Heavy / isolation & purification*
Oryza / chemistry
Plant Leaves
Quercus / chemistry

Substances

Industrial Waste
Metals, Heavy