Adsorbent Materials

Adsorbent Materials (project PID2021-122923NB-I00)

Within the large variety of materials and components included in electrical and electronic equipment (EEE), in this project (Recovery of scarce and valuable Metals from e-Waste by means of tailor-made adsorbent materials), we specially focus on a specific fraction, the so-called printed circuit boards (PCB). They account for an estimated 3-5 wt.% of e-waste, and are made up of more than 30% by weight of different metal elements, distributed in form of metal layers, joining materials, complex mixtures of metals and multielement alloys.

More specifically, the main proposal of this research is the efficient copper, precious metals (gold, silver, platinum, and palladium, selected for their high value), and critical metals (antimony, considered as a feasibility model of recovery of elements other than noble and transition metals) uptake from the PCB lixiviates produced using novel adsorbents designed for this task, and the following recovery of metals adsorbed, evaluating their re-usability, applying adsorption-desorption cycles.

The two proposed tailor-made classes of materials are hierarchically porous multifunctional activated carbons obtained by using polyacrylonitrile (PAN)-based block copolymers (BCs) as precursors, and functional porous organic polymers (POPs).

The work packages of the project are detailed in the Scheme.

Selected Project outputs

Evaluating the performance of carbon-based adsorbents fabricated from renewable biomass precursors for post-combustion CO2 capture

V Rahimi, A Ferreiro-Salgado, D Gómez-Díaz, MS Freire, J González-Álvarez

Separation and Purification Technology 2024, 344, 127110

Adsorption of anionic wood dyes on KOH-activated carbons from Pinus radiata sawdust

CH Pimentel, R Castro-Agra, MS Freire, D Gómez-Díaz, J González-Álvarez

Biomass Conversion and Biorefinery 2024, 1-20

S/N/O-Enriched Carbons from Polyacrylonitrile-Based Block Copolymers for Selective Separation of Gas Streams

D Gómez-Díaz, L Domínguez-Ramos, G Malucelli, MS Freire, J González-Álvarez, M Lazzari

Polymers 2024, 16 (2), 269

Screening of variables affecting the selective leaching of valuable metals from waste motherboards’ PCBs

V Rahimi, EA Inzulza-Moraga, D Gómez-Díaz, MS Freire, J González-Álvarez

Environmental Science and Pollution Research 2024, 1-16

Continuous Adsorption of Acid Wood Dyes onto an Activated Carbon Prepared from Pine Sawdust

CH Pimentel, MS Freire, D Gómez-Díaz, J González-Álvarez

Applied Sciences 2024, 14 (2), 841

Effect of fabrication conditions on the porous structure of polyacrylonitrile-derived carbons and their influence on dye adsorption and gas separation

L. Domínguez-Ramos, D. Gómez-Díaz, M. S. Freire, G. Malucelli, J. González-Álvarez, M. Lazzari

Surfaces and Interfaces 2025, 73, 107571

Industrial Wood Dyes Removal from Aqueous Solutions by Multifunctional Carbons Derived from Polyacrylonitrile

L. Domínguez-Ramos, I. Tejado, M. S. Freire, D. Gómez-Díaz, G. Malucelli, J. González-Álvarez, M. Lazzari

Molecules 2025, 30, 3391

Development and Characterization of Biomass-Derived Carbons for the Removal of Cu2+ and Pb2+ from Aqueous Solutions

V. Rahimi, C. H. Pimentel, D. Gómez-Díaz, M.S. Freire, M. Lazzari, J. González-Álvarez.

C Journal of Carbon Research 2025, 11, 2

Two-stage leaching strategy for the selective recovery of base and precious metals from waste motherboard PCBs: Kinetic study and process optimization

V Rahimi, D Gómez-Díaz, MS Freire, M Lazzari, J González-Álvarez

Separation and Purification Technology 2026, 387, 136665

Congress contributions (selection)

6th International Conference on Green Chemistry and Sustainable Engineering (GreenCHEM-24), Lisboa, Portugal, July 24-26, 2024:

V. Rahimi, D. Gómez-Díaz, M.S. Freire, M. Lazzari, J. González-Álvarez "KOH-activated carbons prepared from biomoss precursors for copper recovery from waste printed circuit boards"
C.H. Pimentel, A. Rial-Pomares, V. Rahimi, M.S. Freire, D. Gómez-Díaz, M. Lazzari, J. González-Álvarez "Removal of methylene blue and malochife green from aqueous solutions by adsorpfion onto KOH aclivated carbon from almond shells"

Oral contribution at the 35th Polymer Degradation Discussion Group (RSC), Limassol, Cyprus, June 23-26, 2024:

L. Domínguez-Ramos, D. Gómez-Díaz, M.S. Freire, J. González-Álvarez, M. Lazzari "Functional carbons with controlled porosity from the controlled degradation of polyacrylonitrile-based block copolymers"

Oral contributions at the 12th International Conference on Sustainable Solid Waste Management (Cyprus 2025). Paphos (Cyprus):

V. Rahimi et al. "CO2 separation by adsorption with biomass-based carbon adsorbents activated with ZnCl2 and H3PO4"
V. Rahimi et al. "Kinetic analysis of selective copper and zinc leaching from printed circuit boards"

Oral contribution at the 33rd European Biomass Conference & Exhibition (EUBCE 2025), Valencia (Spain):

V. Rahimi et al. "Almond shell-based activated carbons for the removal of Pb2+ from aqueous solutions"