Making methanol by pulling CO2 out of the air - Science Daily

[Bill USA]

http://www.sciencedaily.com/releases/2011/05/110505162938.htm

Pulling valuable fuels out of thin air? It sounds like magic, but Joel Rosenthal, a chemist at the University of Delaware, is working to transform carbon dioxide (CO2), a greenhouse gas in the atmosphere, into gas (gas? the article doesn't say anything about gasoline, it does mention making methanol from the CO2__Bill U) for your car and clean-energy future fuels.

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Rosenthal and his team are designing electrocatalysts from metals such as nickel and palladium that will freely give away electrons when they react with carbon dioxide, thus chemically reducing this greenhouse gas into energy-rich carbon monoxide or methanol.

Besides its use in making plastics, solvents, carpet and other products, methanol fuels race cars in the United States and currently is being researched as a hydrogen carrier for fuel cell vehicles.

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The catalytic reduction of carbon dioxide to carbon monoxide is an important transformation that would allow for the mitigation of atmospheric CO2 levels, while producing an energy-rich substrate that forms a basis for fuels production," Rosenthal says.

[skepticscott]

1. Sorry, but you can't get

methane (or methanol) from carbon dioxide without putting just as much energy in as you get back out when you burn the methane back to carbon dioxide. There's nothing to be gained here, as least not as it's described. Catalysts do NOT reduce the amount of energy required to make the transformation. They only increase the RATE of the conversion reaction.

[phaseolus]

2. They admit that

"The chemistry we're doing is energetically uphill -- it's an energy-storing process rather than a downhill, energy-liberating process," he notes. "And our goal is to make liquid fuel renewably from wind and solar sources, not from typical fossil fuel bases."

[skepticscott]

4. That's fine

but nothing new. Processes to do that have been around a long time. There may be things we still need liquid fuels for far into the future, no matter how well developed our renewable electrical capacity becomes, but the more steps we take to produce them, the more energy is lost through inefficiencies.

[Bill USA]

3. the article says that. What they are thinking of is using power from wind and solar sources to take

CO2 out of the atmosphere and make methanol and other chemicals from it. Any CO2 released in combustion of the methanol is returning CO2 to the atmosphere that was previously removed ...unlike fossil fuels the combustion of which adds CO2 to the atmosphere. so at least they are not adding to the CO2.

"The chemistry we're doing is energetically uphill -- it's an energy-storing process rather than a downhill, energy-liberating process," he notes. "And our goal is to make liquid fuel renewably from wind and solar sources, not from typical fossil fuel bases."

[NickB79]

5. The methanol would function as a way to store excess solar and wind energy

Similar to a battery, but possibly much cheaper and more scalable than current schemes using pumped hydro, flywheels or massive electrochemical batteries.

For example, when there is more electricity being generated from wind than the grid needs, we currently just shut off the turbines and squander massive amounts of energy. With a methanol system set up, that excess electricity could be redirected to the plant whenever avaiable.

[RC]

6. Something doesn't sound right.

Methane is CH₄. Where are they getting the 4 missing Hydrogen molecules from? Anyway, burning methane gives you carbon dioxide and water again. I don't see the any gain from this.

[skepticscott]

7. There is no energy gain

Just conversion to a form that may be more useful and necessary for certain applications. But energy is wasted every time you make such a conversion, over and above using electricity from solar or wind sources directly.

[buddysmellgood]

8. Would it make efficient energy storage?

[kristopher]

9. There isn't enough information to know.

There are already technologies out there that can do this but they are not even on the radar of planners. Compressed hydrogen has been seen for quite a while as the most promising method of storing electrical energy in a high density liquid form, but that has been overtaken by the improvements in the energy density offered by lithium batteries.

This approach might be something new but it faces an inescapable and significant hurdle by design - the concentration of CO2 in the air is so low (for this purpose, not for AGW) that it requires using energy to move a huge volume of air across the material - and that requirement is a big energy sink there is no way to get around.

In the past, this type of approach has been popular with coal and nuclear enthusiasts because of the nature of centralized power. I'm interested in hearing more because this is the first time I've heard it suggested as a match with renewables.

We need liquid fuels for a lot of applications besides personal transportation, but to my knowledge the most promising avenue for them is next generation biofuels.

[skepticscott]

10. That's a fair conclusion

these technologies are just too new to know yet for certain which is the most efficient. Compressed air storage is another that's been proposed, but any time you convert energy (like solar or wind-generated electricity) that is not needed at the time it is produced into a form that allows it to be stored until it IS needed, there are inevitable losses/inefficiencies in converting to the stored form, and then back to electricity.