Glass-based inorganic membranes for copper adsorption from wastewater
LAGO D. 1, KRAXNER J. 1, GALUSEK D. 2, BERNARDO E. 3
1 FunGlass – Centre for Functional and Surface Functionalized Glass, Alexander Dub?ek University of Tren?ín, Študentská 2, 911 50, Tren?ín, Slovakia; 2 Joint Glass Centre of the IIC SAS, TnUAD and FChFT STU, 911 50, Tren?ín, Slovakia; 3 Department of Industrial Engineering, University of Padova, Via Marzolo 9, Padova, 35131, Padova, Italy
This work aims to assess a novel glass-based membrane for the immobilization of copper present in wastewater. Boro-alumino-silicate glass culet (BASG) from discarded colorless pharmaceutical vials was used as the starting material. The inorganic membrane was synthetized using weak alkaline solutions (NaOH-KOH 2.5 M) according to the designed solid-to-liquid ratio (60:40). Highly porous structures (33 % overall porosity, of which 30 % was open) were stabilized by the gelation of suspensions and drying at 40 °C for 14 days. The adsorption of copper from an aqueous solution by a glass-based membrane was investigated, and the effect of pH on the adsorption was highlighted. The adsorption of copper is highly dependent on the pH of the solution. The final immobilization of the adsorbed copper was carried out by viscous flow sintering at 700 °C for 1 hour. The homogeneity of the incorporated waste and its distribution within the membrane was characterized by scanning electron microscopy (SEM) with EDS detector. The proposed experimental procedure led to the development of a novel promising metal ion sorbent.