Development of novel active and cost-effective catalysts for pure hydrogen production process, integrated with CO2 utilization.

Project leaders

Annamaria Venezia, Tatyana Tabakova

Agreement

BULGARIA - BAS - Bulgarian Academy of Sciences

Call

CNR/BAS triennio 2019-2021 2019-2021

Department

Chemical sciences and materials technology

Thematic area

Chemical sciences and materials technology

Status of the project

New

Research proposal

Environmental protection is one of the major issues facing the world today. Clean air is vital for good health. Yet despite growing recognition of this imperative, the problem of air pollution is far from solved in many countries, and the global health impacts risk intensifying in the decades to come. The ever increasing CO2 emission due to the consumption of fossil fuels accounts for over half of the enhancement in the greenhouse effect that causes global warming. The limited availability of fossil energy resources and the necessity to reduce the world wide carbon emissions require a dramatic restructuring of todays energy technology to be implemented within the next decades. Hydrogen is recognized as an economically viable, financially attractive, and socially beneficial solution. On these premises, the main goal of the present proposal is related to the development and understanding of an integrated catalytic process for pure hydrogen production coupled with CO2 utilization.
Small stacks of proton exchange membrane fuel cell (PEMFC) have started nowadays to be commercialized for residential use. These devices generally use hydrogen produced by methane catalytic reformers, which, along with hydrogen, produce large amount of CO (> 10 vol. %) and CO2. The use of hydrogen in the proton exchange membrane (PEM) fuel cells requires CO clean-up processes to prevent the poisoning of fuel cell anodes. The WGS reaction (CO+H2O producing H2+CO2) is the preferable step in fuel processors for preliminary purification from CO and additional hydrogen generation. However, the CO concentration after WGS reactor is about 1 vol. %. Considering the extremely high sensitivity of platinum anode in PEM fuel cells to CO, the amount of CO in hydrogen has to be reduced to below 10 ppm. Even with structural and chemical improvement of the anode materials, CO below 100 ppm is still needed for CO-tolerant alloy anodes.
The research efforts will then be focused on development of a new generation of effective, low-cost, alternative catalytic materials with pre-defined properties for CO-free hydrogen production through the processes of dry methane reforming (DMR), water gas shift reaction (WGSR) and preferential CO oxidation (PROX), as well as development of novel sorbents for CO2 capture and utilization.
New nickel catalysts characterized by high activity at the lowest as possible temperature and by an improved tolerance to carbon deposition for the dry reforming of methane will be developed. The strategies adopted in order to increase the activity and decrease the carbon poisoning include the support formulation, the support morphology and the doping of the nickel catalysts with other elements. We propose to alloy nickel with a second metal attaining a twofold effect; morphological effect consisting essentially in the tuning of the active ensemble size and electronic effect consisting in the modification of the intrinsic site activity. As recently reported by the group in Palermo, alloying Ni with noble metals in quite small amount has produced active and also rather stable Ni catalyst [1]. Moreover, mesoporous supports, which by limiting the size of the nickel particle below 15 nm, would hinder the carbon formation, would be investigated.
The unique catalytic properties of supported nanosized gold particles make them promising for hydrogen purification via WGSR and PROX [2-4]. It was reported that the catalytic activity and selectivity is controlled mainly by gold particles dispersion, the nature of support materials and the specific interaction between gold and support. However, additional investigations are still necessary in order to gain deeper insights into the active sites of the catalytic reactions over these complicated systems. In order to develop well-performing and economically viable formulations we shall prepare gold catalysts deposited on cheaper commercial support (alumina) modified by transition metal oxides (Cu, Mn) or SnO2, as well as on some functionalized porous materials. The effect of the nature of metal oxide additives and their amount, as well as method of alumina modification on the gold particle size and the supports structural peculiarities will be studied.
Solid sorbents are widely used to bind the CO2 on their surfaces. Large specific surface area, high selectivity and high regeneration ability are the main criteria for sorbent selection. The adsorption efficiencies of zeolites are largely affected by their size, charge density and chemical composition of cations in their porous structures. In order to reduce the total costs of CO2 capture and to increase the positive effect on environment we plan to produce zeolite and zeolite-like sorbents by using of fly ashes from residues from Bulgarian power plants.

1]. A. Horváth, L. Guczi, A. Kocsonya, G. Sáfrán, V. La Parola, L. F. Liotta, G. Pantaleo, A. M. Venezia, Sol-derived AuNi/MgAl2O4 catalysts: formation, structure and activity in dry reforming of methane, Appl. Catal. A, 468 (2013) 250-259.
2]L. Ilieva, T. Tabakova, G. Pantaleo, I. Ivanov, R. Zanella, D. Paneva, N. Velinov, J.W. Sobczak, W. Lisowski, G. Avdeev, A.M. Venezia, "Nano-gold catalysts on Fe-modified ceria for pure hydrogen production via WGS and PROX: Effect of preparation method and Fe-doping on the structural and catalytic properties", Appl. Catal. A, 467 (2013) 76-90.
3]L. Ilieva, P. Petrova, T. Tabakova, G. Pantaleo, V. Montes, J.W. Sobczak, W. Lisowski, Z. Kaszkur, M. Boutonnet, A.M. Venezia, Pure hydrogen production via PROX over gold catalysts supported on Pr-modified ceria, Fuel, 134 (2014) 628-635.
4]L.Ilieva, P. Petrova, G. Pantaleo, R. Zanella, L.F. Liotat, V. Georgeiv, S. Boghosian, Z. Kaszkur, J.W. Sobczak, W. Lisowski,A.M. Venezia, T. Tabakova, Gold catalysts supported on Y-modified ceria for CO-free hydrogen production via PROX, Appl. Catal. B, 188 (2016) 154-168.

Research goals

One objective of the proposal is to achieve a nanoscale catalytic systems with high activity, selectivity and long-term stability for pure H2 production suitable for fuel cells application. The proposed integrated process offers the opportunity to: (i) reduce the greenhouse gas CO2 emissions by the application of a combined cycle of fully CO2 utilization; (ii) solve the serious problem of PROX catalysts deactivation in the presence of CO2. A second objective is related to an original approach for CO2 capture downstream to the WGS reactor, followed by CO2 recovering and its use as a reagent in the dry reforming reactor. The knowledge generated in the frame of this project will lead to publication in high impact factor catalytic journals and presentation at International scientific meetings. As added value, the specific knowledge might find practical application involving companies working in the field of PEM fuel cell devises. Italian and Bulgarian groups have complimentary capabilities and distinct experience in the subject. Bulgarian team(IC-BAS) started the pioneering investigations of WGS reaction over gold catalysts. The team has a strong expertise in the preparation, characterization and catalytic tests. The Italian team (ISMN) has well documented knowledge in heterogeneous catalysis and in the structural and surface characterization by XRD and XPS as well as in DRM and PROX catalytic tests. Both teams have jointly worked in the frame of NATO and COST action projects.

Last update: 08/06/2025