
Minerals Webinar | Critical Metals Extraction Processes for a Greener Future
Part of the MDPI Minerals Webinar Series series
21 August 2025, 14:00 (CEST)

extractive metallurgy, critical metals, electronic waste, slags
Welcome from the Chairs
1st Webinar on Minerals
Critical Metals Extraction Processes for a Greener Future
Today, we are experiencing rapid growth in the number of initiatives contributing to a sustainable energy transition. However, in many cases, there is a limited supply of critical metals to support future demand for manufacturing devices for electric transport, green energy production, and the ever-increasing consumption of communication and entertainment gadgets. From this perspective, it is imperative to develop new routes to exploit atypical (non-metallurgical) sources of metals, thereby lowering the gap between future demand and the expected supply and avoiding the hindrance of energy transition goals. In this context, the use of complex raw materials in the metallurgical industry, such as urban residues, low-grade mineral occurrences, as well as industry wastes (slags) and effluents, for example, is not only desirable but necessary in order to achieve such goals. Moreover, thermodynamic and kinetic modeling processes, as well as transport phenomena related to such challenging reaction systems, provide important foundations for the development of efficient extraction routes, supporting efficient and economically viable plant and equipment projects.
Date: 21 August 2025
Time: 2:00PM CEST | 8:00AM EDT | 8:00PM CST (Asia)
Webinar ID: 848 4007 4896
Webinar Secretariat: journal.webinar@mdpi.com
Event Chairs

Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, USA
Current Postdoc Associate at Massachusetts Institute of Technology in the Department of Materials Science and Engineering. Has an interest in the recovery of critical raw materials: electrochemical separation, sustainable mining, urban mining, (electro)hydrometallurgy, membrane separation and synthesis of greener materials, recycling of e-waste, brine processing, and the circular economy. Received the Best Thesis Award in Environmental Sustainability (2022) and Academic Productivity Award (2021). Among the top 2% of most relevant researchers in the world according to Stanford/Elsevier.

Chemical and Materials Engineering Department (DEQM), Pontifical Catholic University of Rio de Janeiro (PUC-Rio), Brazil.
Dr. Rogério Siqueira graduated in Chemical Engineering from PUC-Rio in 2002, and, at the same institution, he obtained his master's degree in 2005 and his doctorate in 2009 from the Department of Chemical and Materials Engineering (DEQM), working intensively with computational and experimental thermodynamics. Between 2010 and 2013, he worked as a postdoctoral fellow at DEQM/PUC-Rio in the area of pyrometallurgical processes applied to metal extraction, and also focused on the synthesis of oxidized nanocatalysts. Since then, he has worked as an adjunct professor and researcher at DEQM/PUC-Rio. Between 2015 and 2017, the professor assumed the role of coordinator of the Chemical Engineering course at PUC-Rio and is currently a member of the management committee of NANOFAB, a multi-user laboratory for the characterization of nanomaterials, under the direction of the Department of Mechanical Engineering at the State University of Rio de Janeiro (UERJ). He has a strong interest in the areas of the synthesis of oxidized nanocatalysts using cellulose nanofibers as reactive support, with a focus on applications aimed at hydrogen generation, the use of cellulose nanofibers for the removal of metals from aqueous bodies, as well as in the thermodynamic modeling of fluid systems with strong deviations from ideality, such as those associated with the absorption of acid gases (e.g. CO2 or H2S) in solutions containing amines at high pressures, as well as systems containing hydrocarbons and alcohols, using both equilibrium data (ELV or ELL) and chemical activity generated by the COSMO-SAC formalism.
Invited Speakers

Chemical and Materials Engineering Department (DEQM), Pontifical Catholic University of Rio de Janeiro (PUC-Rio), Brazil
Gabriel is a Materials Engineer who graduated from PUC-Rio in December 2008, with an MSc from the same institution in 2011. He is a specialist in melting, the primary and secondary refining of steel, as well as the thermodynamics and kinetics of chemical reactions, with extensive experience in electric arc furnace (EAF) technology for steelmaking. This includes expertise in both chemical and electrical aspects, as well as alloy addition modeling for ladle furnaces. He is a Steelmaking Technical Manager at Gerdau and enrolled in the doctoral program at DEQM/PUC-Rio, expected to be completed in 2027.

Postgraduate Program in Materials Science and Engineering (PPGCEM), Unesc, Brazil
Professor Eduardo Junca has a PhD in Metallurgical and Materials Engineering from USP with a sandwich period at the University of Utah, a master’s in Metallurgical and Materials Engineering also from USP (2009), graduated in Production Engineering from Universidade Nove de Julho (2018), and graduated in Technology in Metallurgy and Materials from the Federal Institute of Education, Science and Technology of Espírito Santo. He is currently a Permanent Professor of the Postgraduate Program in Materials Science and Engineering at the Universidade do Extremo Sul Catarinense, where he develops research projects in the research areas of urban mines, extractive metallurgy, and waste and materials processing.

Department of Mining and Petroleum Engineering, USP, Brazil.
Dr. Carlos Oba has a degree in Geology from the University of São Paulo (1985), a PhD in Materials Science and Engineering from the Institut National Polytechnique de Toulouse/France (2000), and a PhD in Mineral Engineering from the Polytechnic School of the University of São Paulo (2000). He holds a post-doctorate from the Institute of Geosciences of the University of São Paulo (2002). He has experience in the area of geosciences, with an emphasis on mineralogical and technological characterization of mineral raw materials, working mainly in the following areas: mineral research, mining law, the technological characterization of ores, mineral processes, phosphates, and fertilizers.
Registration
This is a FREE webinar. After registering, you will receive a confirmation email containing information on how to join the webinar. Registrations with academic institutional email addresses will be prioritized.
Certificates of attendance will be delivered to those who attend the live webinar.
Can’t attend? Register anyway and we’ll let you know when the recording is available to watch.
Program
Speaker/Presentation |
Time in CEST |
Time in EDT |
Dr. Amilton Barbosa Botelho Junior (Chair) and Dr. Rogério C.S. Navarro (Co-Chair) Chair Introduction |
2:00 - 2:10 pm |
8:00 – 8:10 am |
Mr. Gabriel Medeiros (Speaker 1) Non-Ferrous Recovery On EAF Steelmaking |
2:10 - 2:30 pm |
8:10 – 8:30 am |
Prof. Eduardo Junca (Speaker 2) Alternative Routes For Niobium Oxide Extraction |
2:30 - 2:50 pm |
8:30 – 8:50 am |
Dr. Carlos Oba (Speaker 3) Studies Of Extraction Processes Of Critical Metals From Unconventional Sources |
2:50 - 3:10 pm |
8:50 – 9:10 am |
Q&A |
3:10 - 3:25 pm |
9:10 – 9:25 am |
Closing of Webinar Dr. Amilton Barbosa Botelho Junior (Chair) and Dr. Rogério C.S. Navarro (Co-Chair) |
3:25 - 3:30 pm |
9:25 – 9:30 am |
Relevant Special Issue
New Extraction Processes for Critical Metals from Non-Metallurgical Resources
Guest Editors: Dr. Amilton Barbosa Botelho Junior and Dr. Rogério C.S. Navarro
Deadline for manuscript submissions: 31 January 2026