RICERCA ITALIANA     

Sustainable processes of 2nd generation for the production of H2 from renewable resources

Università degli Studi di Trieste

Abstract

The use of hydrogen as clean vector for a sustainable energy requires to develop new technologies for H2 production from renewable resources, as indicated both in the European contest and in the national one.

However, a real sustainable use of H2 requires to move from production processes of 1st generation, based on the utilization of raw materials such as bio-ethanol and glycerine to processes of 2nd generation which use products of hydrolysis of (lingo)cellulose and operate in solution.

These requires:
(i) the use of more abundant, available and less costly biomasses, e.g. utilization of 2nd generation biomasses (lignocellulose);
(ii) the direct production of H2 from uphill products to reduce the number of the process steps, e.g direct production of H2 from solutions of hydrolysis of the cellulose (possibly even integrated in the hydrolysis stage) instead that from bioethanol produced in turn by fermentation of these solutions of hydrolysis of the cellulose;
(iii) operate the process reforming in liquid phase and at low temperature, to reduce the energy requirements and costs of the process.

The typical approach adopted in the 1st generation processes is
(1) the catalytic steam reforming carried out in vapour phase, while two are the possible alternatives which satisfy the above requirements;
(2) the aqueous phase reforming using heterogeneous catalysts;
(3) the liquid phase >>>

Principal Investigator

Paolo Fornasiero Università degli Studi di TRIESTE

Research Objectives

The use of H2 as an energy carrier for a sustainable development, which has been recognized as a priority in an European as well as national context, requires a research investment for the development of new technologies for H2 production from renewable sources, being not competitive with the food sector, as has been remarked by the United Nations. In this regard, also the Minister of the Environment has recently stated that moving the energy production technologies from the use of first generation biomasses (corn, wheat, vegetal oils etc.) to second generation ones (wood cellulose) is highly desirable.

Regarding the H2 production processes from biomasses, the above point means to move from the use of ethanol and glycerine to the use of wood cellulose as starting materials. In turn, this implies the need for (i) H2 production processes in the liquid phase (differently from ethanol and glycerine, wood cellulose does not allow gas phase reactions; liquid phase operation requires the development of new catalysts, but has the advantage of allowing considerable energy savings, since the vaporization of large amounts of reagents is avoided), (ii) processes which must include an integrated catalized depolymerization stage of the wood cellulose and (iii) processes able to be run at low temperature, in order to limit the energy costs.

Thus, to invest into a sustainable energy development means to invest into the development of new, second generation >>>

First Results

The expected results from research, and their interest both for scientific advancement of knowledge and for the application perspective can be differentiated between those arising from the project as a whole, e.g. as the added value resulting from the project itself, and those arising from the specific studies of the participating UdRs. To note that the project has a highly innovative character and as a consequence, in the limited time of two years for the project and the limited resources available, it is possible only an advancement of knowledge towards the realization of the second generation processes for the production of H2 (in particular, with reference to the development of new nanostructured catalysts), but it is not realistic to believe that all the problems relating to the implementation of research results can be solved.

Exploitability of the results

Considering the potential interest of the results, already two of the main industries in the sector have expressed, with specific letters of support, their interest for the realization of the research project. ACTA spa (http://www.acta-nanotech.com) is a very active SME in the field of applications of nanotechnology to the energy sector. Since 2005 ACTA spa is listed on the stock market and has offices and research laboratories both in Italy and in UK. The activity of ACTA deals with the development of fuel cells and electrocatalytic devices using especially renewable raw materials >>>

Timescale

24 months

National and international background

H2 fuel cells offer enhanced efficiency in power generation without pollutant emissions. However, the full environmental benefit is only achievable if H2 is produced in a sustainable way and from renewable resources [1]. There is agreement on the need to pass from processes of the 1st
to those of the 2nd generation in the production of biofuels, e.g. to use biomasses more available and which do not compete with food uses (ligno-cellulose biomasses) instead of producing bioethanol from corn and biodiesel by transesterification of vegetable oils.

Currently the H2 is produced mainly by steam reforming in the gas phase of fossil fuel [2], and it is used mainly where it is produced (in refinery, for example). The forecasts indicate an exponential increase of the demand of H2, mainly outside of the traditional uses and the places of production [2]. In all these applications and in order to limit the emissions of CO2, it is interesting to produce H2 from renewable sources in medium-small plants. For example, to produce H2 for public transport in the cities. Beside the possible production by electrolysis (still expensive), it is necessart to develop technologies to produce H2 from biomasses (project EU HyFLEET: CUTE dedicated to the use of H2 in several European cities for local mobility). Thermochemical approaches (pyrolysis or gasification) cannot be used effectively for these medium-small productions [3] and therefore it is interesting to produce H2 from >>>