(409c) Production of Hydrogen Via Partial Dehydrogenation of Fuels

Mélanie Taillades,Julien Belloc, Gilles Taillades, Deborah Jones, Jacques Rozière

 

Institut Charles Gerhardt UMR 5253, Agrégats, Interfaces et Matériaux pour lâ??Energie,

Université de Montpellier, Place Eugène Bataillon, 34095 Montpellier Cedex 5, France

One of the objectives of the industries is to provide more efficient and greener transport environment [1]. In this context a new generation of more electrified vehicles must be developed. One of the technologies on this roadmap is a fuel cell secondary power generation unit replacing the current Auxiliary Power Units (APU) [2-4] and proton exchange membrane fuel cells (PEMFC) are the best candidates for the role as an APU replacement. PEMFC operate on pure hydrogen and air between 50 to 100 °C (120 to 200 °C for high temperature PEMFC), and produce electricity and water, with heat and oxygen-depleted air as by-products

The two main issues for the actuation of such an energy system based on hydrogen are its production and storage. Hydrogen production mainly relies on fossil fuels and application to the transport sector would mean a big increase of the demand and hydrogen storage has the drawback of weight, overall storage size and security. This means a big challenge to find a safe and economic way to store it and make it available for applications of interest, in particular for transportation on-board application.

Among the different processes for the hydrogen delivery to fuel cells, a promising one is the generation of hydrogen by catalytic dehydrogenation of liquid hydrocarbons (HCs). This seems to be an appropriate solution as it can produce the hydrogen directly from vehicle fuel, but is only feasible if the process is able to produce sufficient pure hydrogen.

Ours works are based on the concept for hydrogen generation by partial dehydrogenation (PDh) of fuels, allowing the production of dehydrogenated hydrocarbons in liquid phase and hydrogen in gaz phase [5, 6, 7]. Hydrogen has high purity and is CO₂ free, allowing the direct alimentation of fuel cells for supply of electrical energy to auxiliary systems, without a purification step. The liquid phase, composed of partially dehydrogenated hydrocarbons, maintains its original fuel properties with the requisite specifications to be reused as fuel. This process allows the production of hydrogen either on board with the PDh of the vehicle fuel or in a generator connected to the existing fuel storage facilities. The modified fuel can be re-injected into the pool of the vehicle or in fuel storage existing facilities.

This work describes research works on the partial dehydrogenation of gasoline for the production of enough pure hydrogen to feed a fuel cell on board a car. The choice of the catalyst is crucial for the partial dehydrogenation process; it must produce H₂ without compromising the original fuel properties. An ideal catalyst must generate sufficient hydrogen of high purity, be selective to dehydrogenation and avoid cracking reactions responsible for coke deposition and catalyst deactivation. Advanced material, composed by an active phase of 1% Pt-1 % Sn impregnated on a new γ-alumina type support has been developed, characterized and evaluated as a catalyst in the reaction of partial dehydrogenation. The influence of catalyst composition on the activity, selectivity and stability as well as a regeneration mechanism were studied. This material allowed a hydrogen production of 2500 NL.h-1.kgcat^-1, with a purity of 85% vol. corresponding to 21.3 NL.L_fuel^-1 which can generate an electrical power supplied by a fuel cell of 2.5 kW. This process allows a hydrogen production on-board or in distribution sites.

[1] ITF, I. T. F. Reducing transport ghg emissions: opportunities and costs; 2009

[2] Carter, D.; Wing, J. The Fuel Cell Industry Review; 2013

[3] U.S.DOE. Hydrogen production and delivery: summary of annual merit review of the hydrogen production and delivery program; 2013

[4] U.S.DOE. Hydrogen , Fuel Cells & Infrastructure Technologies Program - multiyear research, development and demonstration plan; 2010.

[5] Resini, C.; Lucarelli, C.; Taillades-Jacquin, M.; Liew, K.-E.; Gabellini, I.; Albonetti, S.; Wails, D.; Roziere, J.; Vaccari, A.; Jones, D. Int. J. Hydrogen Energy 2011, 36, 5972â??5982

[6] Gianotti, E.; Reyes-Carmona, Á.; Taillades-Jacquin, M.; Taillades, G.; Rozière, J.; Jones, D. J. Appl. Catal. B Environ. 2014, 160-161, 574â??581.

[7] Gianotti, E.; Taillades-Jacquin,M ; Reyes-Carmona, A; Taillades, G.; Rozière, J.; Jones, D. J. Appl. Catal. B Environ. 2016, 185, 233-241