Cracking the hydrogen-fuel riddle

A Hebrew U scientist finds a solution for hydrogen in automotive engines.

By JUDY SIEGEL-ITZKOVICH
Lab 311 (photo credit: Bloomberg)
Lab 311
(photo credit: Bloomberg)
Hydrogen, main component of water, has long been regarded as a potentially ideal, non-polluting and renewable energy source for cars. It is the lightest and most abundant element, comprising about three-quarters of the universe’s mass. But problems involved in producing, transporting and storing it in a safe, economical manner have stymied researchers for years.
Now a doctoral candidate in chemistry at the Hebrew University of Jerusalem believes she has come up with a practical solution for automotive engines. Clarite Azerraf has presented her proposal for a unique, in-car, catalyst-based process she says will produce hydrogen through the use of alcohol or alkanes – saturated chemical hydrocarbon compounds found mostly in natural gas and oil.
The initiative, by Azerraf and her mentor, Prof. Dmitri Gelman, has been patented through Yissum, the HU’s technology transfer company. For her work, she won one of this year’s Barenholz Prizes, which was presented last week during the university’s board of governors meeting. The award is named for its donor, Prof. Yehezkel Barenholz of the HU-Hadassah Medical School.
Through a reverse reaction process, Azerraf says she has demonstrated that it is possible to break up the alcohol or alkane hydrocarbon compounds and receive pure hydrogen and other versatile products through the use of the metal iridium as a catalyst.
Iridium, Azerraf says, has been shown to have an exceptional stability and an ability to catalyze a hydrogen transfer reaction of this sort.
Today, the refined hydrocarbons (gasolines) burned in the presence of oxygen in our car engines produce the energy that enables the car’s operation, but also produce carbon dioxide, one of the main greenhouse gases. The process Azerraf suggests produces an alternative source of energy that she says will ultimately reduce pollution, since the only waste products are water and heat.
With her system, cars will have tanks holding alcohols or alkanes that will be fed into an on-board reactor containing the iridium-based catalyst that will produce the hydrogen. When burned, the hydrogen will then power fuel cells that will produce the energy to operate an electric car engine. The system will be designed in such way that the fuels will be transported into the reactor in the right time and amounts as required at any giving moment to operate the car.
The end result will be quiet, nonpolluting vehicles that will not consume depleting fossil fuels.
Azerraf acknowledges that there is currently much and divergent research involving the production of hydrogen, and that her process is still very far from being implemented. But, she says, the fact that the iridium catalyst she has developed is the best one known to date in hydrogen transfer reaction shows its huge potential for the future.
GOING TO THE ‘OPERA’ After seven years since the start of construction of the OPERA experiment and three years of operation in the underground Gran Sasso Laboratory of the Italian National Institute of Nuclear Physics (INFN), one of the many billions of muon neutrinos produced at the CERN accelerator complex (CNGS) has likely “transformed” into a tau-neutrino observed by the OPERA apparatus. This is an extremely important result, according to Haifa’s Technion-Israel Institute of Technology, which was involved in the discovery. OPERA has been designed, realized and is being conducted by a 170-member team from 33 institutions and 12 countries including Belgium, Croatia, France, Germany, Italy, Japan, Korea, Russia, Switzerland, Tunisia and Turkey, as well as Israel.
The observation of a few more of these tau-neutrino events over a large number of conventional muon-neutrino interactions will represent the longawaited proof of the direct conversion of one type of neutrino into another – the so called “neutrino oscillation” mechanism. This is a crucial milestone for neutrino physics made possible by a complex scientific enterprise that has been realized thanks to the skill of a large number of scientists, engineers, technicians and students.
The disappearance of the initial neutrino “flavor” has already been observed by several experiments in the past 15 years, but the “direct appearance” is still the outstanding missing tile of the puzzle, and the OPERA experiment is unique worldwide for this purpose.
Neutrino oscillation is today the only indication of new, fascinating physics beyond the so-called standard model of particles and interactions, opening the possibility of unexpected implications in cosmology, astrophysics and particle physics. The experiment was inaugurated four years ago, when the first “normal” muon neutrinos were detected after a trip of 730 kms. from CERN, covered in about 2.4 milliseconds at the speed of light.
After that, a careful and tireless search started to find the tiny and very special signal induced by a tau-neutrino.
OPERA accomplishes its neutrino detection with its “heart,” comprised of more than 150,000 small units called “bricks,” each equivalent to a sophisticated camera. Thanks to these units, made of a sandwich of lead plates and special photographic films, OPERA researchers can detect details of the “neutrino events” by accurately measuring the elementary particles produced in the interaction of the neutrino with the brick.