An on-board reformer capable of converting exhaust gas into fuel and removing pollutants could help carmakers achieve tough emissions targets.
The fuel efficiency of modern cars has improved by 20 per cent since 2010, as a result of improvements to engine design, weight reductions, and the use of hybrid technologies.
But while these improvements have enabled manufacturers to meet their 2015 targets for reducing carbon dioxide emissions, car makers are still 15-30 per cent short of their 2020/21 target of 95g/km, according to Dr Athanasios Tsolakis at Birmingham University.
To help meet this target, Tsolakis and his colleagues are developing a catalyst-based reformer capable of improving the fuel economy and therefore greenhouse gas emissions of petrol engines.
“The system uses the engine exhaust gas, consisting of heat, water, CO2 and in some cases O2, and fuel to produce a hydrogen-rich gas that is then used for combustion in the engine,” he said.
The on-going EPSRC-funded project, which also includes researchers at Brunel University, as well as Ford and Johnson Matthey, will use platinum/rhodium (Pt-Rh)-based catalysts to produce the hydrogen-rich gas, which can then be used for combustion.
“This means that the engine fuel – gasoline and hydrogen–rich gas – has a higher energy content,” he said.
It should also reduce engine pumping losses by allowing for a more favourable throttle position, said Tsolakis.
The technology can also be designed to reduce emissions from diesel engines, he said.
It can also indirectly improve diesel engine fuel efficiency by improving the performance of after-treatment systems. Existing after-treatment systems can use large quantities of fuel to remove pollutants from the exhaust, but the new reformer would need only a few parts per million of hydrogen to operate, said Tsolakis.
In the first stage of the project, the fuel reformer will be integrated into the exhaust, to provide small quantities of hydrogen-rich gas to the engine’s after-treatment system, when needed.
Later, the researchers plan to develop a compact catalyst brick, designed using additive manufacturing techniques, which can be integrated into the after-treatment system itself in both diesel and lean combustion petrol engines.
This should help to improve the speed of the system’s response to engine or emissions changes.
Once again the superlative properties of hydrogen as fuel are made clear. Hydrogen has the highest burning flame velocity of any fuel, thus allows a more complete burn of the injected hydrocarbon to begin with, and obtaining the necessary hydrogen from the exhaust is a win-win.
There should also be the possibility of retro-fitting existing engines to hydrogen injection/re-injection (as part of the intake air stream).
Using alternating current, and iron (not steel) electrodes, one can generate the needed hydrogen with very little oxygen by-product, since most of the oxygen is converted to iron oxides at the electrodes.
Academia again building something with grants which is inferior to a product which can be bought today: http://fuels.pro
It doesn’t seem to be the same process but an alternative means to the same end!
So many brilliant ideas I read about on this website that are devised in academia, and proven to work on a small scale or on a one-off test bed, sadly don’t seems to make it into mainstream production. What, I wonder, are the large manufacturers such as Ford and GM afraid of? Anyone from a vehicle manufacturing company care to comment?
I used to think hydrogen was too good to be true, just couldn’t find its Achilles heel.
Until I found out it seeps through most metals causing cracking. Bang bang!
I believe Toyota and others are working on special injectors etc, but at the minute, the best solution is to use a bicycle.
And I would love to know the emissions & PM emitted during a DPF regeneration (diesel engines).
I have a U.S. Patent ( 6,981,367, Issued January 3, 2006) for an electrolyzer that produces hydrogen from the water vapor contained in the exhaust of a diesel engine:
http://www.keithdpatch.com/keith-d-patch-patents.html
Unfortunately, there are scant details on the system of Tsolakis; but it sounds like a very similar system. Unfortunately, the energetics of converting water vapor contained in the exhaust of a moving vehicle into a fuel (hydrogen) are very unfavorable. If the hydrogen is just for use as a reductant for catalytically cleaning up the diesel engine’s exhaust, then it might be acceptable.
Best,
–Keith
@KeithDPatch
Fuels pro ice is only for large stationary engines and not mobile. The electrode device sounds similar to a geet one. I have been researching refomative egr for gasoline engines in cars. This sounds very similar to what Precision Combustion has. Could the hot gases be used at fuel injection to vaporize the gasoline mist for better performance too? And as mentioned by Keith will the auto industry back it with warranties or oil industry suppress it as an aftermarket device in this pro fossil fuel administration?