abstract
The mining industry is one of the largest sources of environmental concern globally. Herein we report for the first time the application of highly porous 3D-printed sorbents containing high amounts (50 wt%) of red mud, a hazardous waste derived from the alumina industry, for the remediation of acid mine drainage (AMD). The sorption capacity of the inorganic polymers was initially evaluated for the simultaneous removal of five metal (loid) elements, namely Cu(II), Ni(II), Zn(II), Cd(II) and As(V) in synthetic wastewater. The effect of the initial concentration, pH and contact time were assessed, reaching removal efficiencies between 64% and 98%, at pH 4 and initial concentration of 50 mg L-1 of each cation, after 24 h of contact time. The 3D-printed lattices were then used for the remediation of the real AMD water samples, and the role of adsorption and acidic neutralization was investigated. Lattices were also successfully regenerated and reused up to five cycles without compromising their performance. This work paves the way for the use of an industrial waste derived from the production of alumina as raw material for the management of the hazardous AMD.
keywords
METAKAOLIN BASED GEOPOLYMER; INORGANIC POLYMER SPHERES; HEAVY-METALS; ADSORPTION; MECHANISM; IONS
subject category
Engineering; Environmental Sciences & Ecology
authors
Gonçalves, NPF; da Silva, EF; Tarelho, LAC; Labrincha, JA; Novais, RM
our authors
João António Labrincha Baptista
Full professor
Nuno Gonçalves
Junior Researcher
Rui Miguel Novais
Assistant ProfessorProjects
CICECO - Aveiro Institute of Materials (UIDB/50011/2020)
CICECO - Aveiro Institute of Materials (UIDP/50011/2020)
Associated Laboratory CICECO-Aveiro Institute of Materials (LA/P/0006/2020)
3D Printed Fouling-Resistant Photoactive Membranes for Wastewater Treatment (PURAQUA)
acknowledgements
This work was developed within the scope of the project CICECO-Aveiro Institute of Materials, UIDB/50011/2020, UIDP/50011/2020 & LA/P/0006/2020, GeoBioTec (UID/04035/2022) and CESAM (UIDP/50017/2020, UIDB/50017/2020 and LA/P/0094/2020), financed by national funds through the FCT/MCTES (PIDDAC). The authors would like to thank FCT project MAXIMUM (PTDC-CTM-CTM-2205-2020). Nuno Goncalves acknowledge the funding from the European Union's Horizon Europe research and innovation programme under the Marie Sklodowska-Curie Actions PF grant agreement No 101065059. The authors would like to thank EDM (Empresa de Desenvolvimento Mineiro, Portugal) and Dra. Catarina Diamantino for the support in the AMD sampling campaign.