Unicamp's technology portfolio patent advances on-board hydrogen production with a compact ethanol reformer. The invention can be coupled to fuel cells to electrify the fleet
Researchers from the Optimization, Design and Advanced Control Laboratory (LOPCA) at the Faculty of Chemical Engineering at the State University of Campinas (FEQ Unicamp) developed a compact chemical reactor (microreactor) that enables the production of hydrogen from ethanol. The technology, patented with the support of Inova Unicamp, can be embedded in vehicles and also coupled to fuel cells to power electric cars.
The generation of hydrogen from renewable sources is a topic of global interest as part of the search for solutions to reduce the emission of greenhouse gases, such as carbon dioxide. The so-called green hydrogen is one of the industry's bets on reducing these emissions. The burning of hydrogen results in energy and water, which returns to the environment in the form of vapor.
Some of the electric cars powered by this fuel already carry pressurized gas in tanks, however, as the storage pressure is high, this option requires special care and the assembly of an adequate infrastructure, factors that can be prohibitive in a country with dimensions of Brazil, say the researchers. “Our proposal is the production of hydrogen in cars from ethanol. This hydrogen can power fuel cells, enabling electrification in an easier and cheaper way, using technology developed in the country and reducing CO2 emissions”, explains Rubens Maciel Filho, professor and researcher at FEQ Unicamp.
3D printing ethanol microreactor
The microreactor can be used in different areas, from the pharmaceutical industry to the automotive industry. In these devices, chemical reactions take place in a confined space, having the advantage of intensifying the processes, maximizing heat and mass transfers and, therefore, providing high conversions in a very short time. The prototype, designed and built at Unicamp, is the size of a smartphone and its core, the heart of the system, is just 5 centimeters long. “Due to these characteristics, the efficiency and control of reactions are better when compared to conventional reactors”, highlighted Maciel Filho.
Another advantage is the microreactor production model. The plates, a mesh of microchannels, are made by 3D printing in metal-specific devices. Aligned with Industry 4.0, additive manufacturing allows the use of topology and design optimization software. “3D printing has stood out as a highly applicable technology in different areas of the industrial sector. In the production of microsystems, it is essential, as the design of the internal parts requires a different architecture, which can hardly be reproduced by conventional manufacturing processes, such as machining, casting, forming, among others”, explains André Jardini, who was co-supervisor of the research and is senior researcher at the National Institute of Biofabrication Science and Technology (BIOFABRIS).
Thus, 3D printing facilitates production and also the development of new prototypes more quickly, offering flexibility for creating geometries that improve system efficiencya, which allows us to better meet market expectations. The material used is also relatively common and available in the industry, which avoids the excessive extraction and use of rare minerals, an important aspect from a sustainability point of view. “In addition, to obtain the prototype, optimization and simulation techniques were used, which enabled a very high yield in obtaining hydrogen”, he adds.
To move a vehicle, the hydrogen produced by the reformer must pass through a fuel cell that transforms the gas into electricity, which runs the engine. According to the inventors, the process is already on scale for use. The number of microreactors needed to move a vehicle, however, will depend on the car's specifications. In this proposal, in order to scale up to the power necessary to move a given vehicle, the number of reaction modules is multiplied.
Why ethanol?
Ethanol is a biofuel produced on a large scale in Brazil — the second largest producer in the world. Therefore, we already have infrastructure for the production, storage and transportation of this product, in a production chain that generates jobs and income. “We already have gas stations that supply ethanol, which makes the implementation of electrification using this technology more feasible”, says Maciel Filho. According to the researcher, the solution is a viable alternative for Brazil and may also be viable for other countries with continental dimensions, such as India, which also produces ethanol.
The reduction in pollutant emissions is another advantage. Although the reforming of ethanol to obtain hydrogen generates a certain amount of carbon, this emission can be eliminated when considering the entire agro-industrial chain. “This carbon does not come from a fossil source, as is the case with hydrogen produced from natural gas. This is a reversible process, as this carbon is captured by the sugar cane when it grows”, argues Maciel Filho.
Furthermore, the ethanol used in the process is less concentrated when compared to the hydrated and anhydrous ethanol currently sold, since the reaction depends on the presence of water. Therefore, filling the tank could cost less, as it would eliminate part of the costs involved in obtaining ethanol in the specifications currently required for combustion engines or to be mixed with gasoline. “We are talking about driving the vehicle with practically half the concentration of ethanol that is currently available at the gas station”, says Maciel Filho.
Green Patent
The research that led to the patent was carried out between 2009 and 2013. The invention was protected by the Green Patents program of the National Institute of Industrial Property (INPI). The service identifies new technologies aimed at producing alternative energy that can be quickly used by society, in order to encourage licensing and innovation in the country. Unicamp is now looking for commercial partners to implement the technology, continue its development for specific uses and allow the manufacture of reactors on an industrial scale. “The use of 3D printing with different technologies and materials allows innovative ideas and projects to be materialized into real objects that must, at an initial stage, in the concept of prototypes, undergo validation tests”, highlights Jardini. According to the team [which team?], at the current stage of the research, companies in the sector may already be interested in accelerating the testing and adaptation process for use at the specified powers.
“Subsequently, the same 3D printing technology can be used in the productive part of manufacturing, optimizing different process steps and reducing production costs, in addition, of course, to minimizing material waste, as this technology works as an additive and non-subtractive”, concludes Jardini. Technology transfer through licensing is carried out with the support of Unicamp's Innovation Agency, and researchers actively participate in this process.
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This text was originally published on the Innovates Unicamp.
