Cheap and clean: Australian company creates hydrogen with near-zero emissions

[n2doc]

n Australian company is using “cheap as dirt” iron ore to convert methane in natural gas into hydrogen. Importantly, their process generates near-zero emissions, as the carbon content of the gas is captured in the form of high-quality graphite.

As a clean-burning fuel, hydrogen could play a key role in future energy markets, but production methods are still too energy-intensive and costly.

Hazer Group is a Perth-based company, spun out of the University of Western Australia, which plans to halve the cost of hydrogen production. It is currently scaling-up its patented process, based on “methane cracking”.

“The chemistry is remarkably simple,” says Geoff Pocock, the managing director of the ASX-listed company, which raised A$5m at its initial public offering in September 2015. “You can think of it as a self-sequestering energy production system.”

As natural gas passes through the heated iron ore catalyst, methane in the gas breaks down into its constituent elements: hydrogen and carbon. But instead of carbon dioxide, would-be emissions are captured in the form of solid graphite.

more
https://www.theguardian.com/sustainable-business/2016/jul/22/cheap-and-clean-australian-company-creates-hydrogen-with-near-zero-emissions

[Statistical]

1. Hydrogen fuel cells are a good way to produce low efficiency high cost electric vehicles n/t

[n2doc]

2. Not everything can be plugged in regularly n/t

[kristopher]

5. I'm a strong critic of pushing a 'hydrogen economy'

But the research in the OP is a line of inquiry that hasn't been part of the picture to date.

I'd like to know more about it because we still have major challenges in several sectors requiring high energy density fuels.

[NNadir]

3. Your title is completely disingenuous and misleading. Filthy natural gas is very much involved.

To call methane, dangerous natural gas, zero emissions, is frankly, an abuse of language.

Almost all of the world's hydrogen is currently made from dangerous natural gas, during which energy is wasted, necessarily, since hydrogen is a component of Haber ammonia, on which the world's food supply depends.

This said, any attempt to use hydrogen from natural gas to fuel devices such as automobiles or power plants is extremely wasteful, dangerous, and deadly.

[n2doc]

4. It ain't my title

And you can take your nuke-loving butt over to ignore. Piss off.

[NNadir]

6. Whatever. The title, no matter who produced it, is a fraud. Period.

The hydrogen scheme is so obviously ridiculous that even people who are not too bright, like say, Joe Romm can see it's ridiculous.

Thanks, by the way, for the ignore. I won't return the favor, since trashing the "hydrogen as our savior" nonsense that's been floating around for half a century now with no real result can be fun.

Of course, if one is still scientifically immature enough to buy into this hydrogen business, one must spend lots of time ignoring things, notably the 2nd law of thermodynamics, assuming that one has heard of that inviolable law that cannot, um, be repealed by Congress or any other organization.

Best regards for the future,

NNadir

[caraher]

7. Did you read the article?

I'd be especially interested in your take on the technical details of this proposal given your chemistry background. The "clean" claim rests in part on the process capturing the carbon from methane in the form of graphite, which means that apart from any methane leaks, the process itself does not add carbon to the atmosphere.

What's not at all clear from the article is what the energy side of the equation really looks like. My guess would be that this process is a net consumer of energy, based on the enthalpy of formation for methane, and thus we're in the same bind as for the usual "renewable electricity --> electrolysis --> H2" route typically championed by hydrogen cheerleaders, just perhaps with different, possibly more favorable numbers.

[eppur_se_muova]

9. Re. energy, see my post below. nt

[eppur_se_muova]

8. I used to wonder about this ... BUT ... what are you going to do with all that graphite ?

High-quality graphite is already produced by this reaction, just with different catalysts (or none at all); remember this is based on a company press release, so discount a certain amount of spin. If graphite could all be converted to carbon fiber, that would be a really interesting development. But even if every manufactured article on Earth were made of carbon fiber, there would still be a surplus of graphite, because energy demands are so much higher than materials demands.

Note that breakdown of methane to its elements is endenthalpic, i.e. consumes energy. But combustion of the H2 produced would return up to four times the energy required (caveat: not 100% efficient, of course). From that POV, it's a win. But no industry is going to let huge stockpiles of unused graphite accumulate -- not when it's a potential fuel, albeit the worst possible carbon fuel.

ETA:
CH4 ----> C + 2H2 –74.7 kJ
2H2 + O2 ----> 2H2O ?286 kJ/mol

One *potential* approach is to convert the excess carbon to carbohydrates -- that's where the name comes from, after all, carbon plus water, and the reverse reaction certainly works (this is how activated charcoal is made). If graphite and water (or natural gas and water) could be converted to formaldehyde, then the formose reaction could be used to make a mixture of sugars, which could be used as a feedstock for microbes. If the materials resulting were eventually recycled in landfill rather than burned, it would amount to reinterment of carbon. Kind of roundabout, but worth thinking about.

Since carbon can already be converted to water gas (CO + H2) and water gas can be converted to methanol (CH3OH), then there should be a way to produce formaldehyde, which is intermediate in oxidation state between the two (the current industrial process requires some oxidation, thus loss of some H2):

CO + CH3OH <----> 2 H2CO

Note the overall process would be

C + H2O ----> CH2O ----> C6H12O6 (e.g.)

for a net conversion of carbon to sugar and thence to starch, cellulose, etc. Could we actually make artificial cellulose for cloth, paper, etc. on a practical basis ?? (Fermentation to produce ethanol or 1-butanol would unfortunately release some CO2, for a net release of carbon.)

[kristopher]

10. Do we have an understanding of how terra pretta works?

https://www.sciencedaily.com/releases/2006/03/060301090431.htm

[OKIsItJustMe]

12. There’s an important difference here

With Terra Preta, in theory, you are sequestering atmospheric carbon. In this case, it is carbon from fossil fuels. (So, ideally, this scheme is carbon neutral, while Terra Preta is carbon negative.)

[kristopher]

13. I'm thinking more along the lines of diminished use of fertilizer

[NNadir]

11. Not really. It's a Guardian article, not a scientific publication. But I looked, since you asked.

For the record, much of the "science" published by the Guardian is nonsense; as is the case for most journalistic publications. I often joke - I'm not sure it's actually a joke - that in modern times one cannot get a journalism degree if one has passed a college level science course.

I'm not a big fan of hype for the purpose of generating funding, especially if I know (on inspection) it's hype.

In any case, this is the reverse of the formation reaction of methane, according to the Guardian article.

The Gibbs Free Energy of this (the reverse of formation, decomposition into the elements) reaction is mildly negative, so theoretically the reaction could be (at least catalytically) spontaneous, but as a practical matter, it surely is not.

It is a continuous problem in catalysis of this type that the catalysts become occluded on the surface with layers of carbon, after which they are useless.

The result is that process handling will surely make the product a net loser, and in any case, the process is useless, since it relies on access to a dangerous fossil fuel.

Most of the world's hydrogen is already made from methane, and frankly, although it is currently essential to food supplies to do this, it is a disaster environmentally for a host of reasons.

When "clean burning" natural gas is burned, one can often see soot forming on smoke stacks. This is a result of the Boudouard reaction, 2 CO <-> C + CO₂. The deposited carbon is the resultant soot. The Boudouard reaction if often a catalyst killer in the reformation of methane, the main source of almost all of the world's hydrogen, almost all of which is for captive use: CH₄ + H₂O <-> CO + 3 H₂. The mixture on the right is syn gas, and usually it is carried further, where ammonia synthesis is the goal, as follows: CO + H₂O <-> CO₂ + H₂. The latter reaction, the water gas shift reaction is one of the most important reactions in industry.

Both reactions are reversible, and the position of the equilibrium is determined by the conditions under which the reaction is conducted.

Note that this reaction could be performed step wise using these reactions:

CH₄ + H₂O <-> CO + 3 H₂

2 CO <-> C + CO₂

An additional reaction is required, the reformation of carbon dioxide with methane: CO₂ + CH₄ <-> 2CO.

A great deal has been written in recent years on the subject of carbon dioxide as an oxidant. I think it is may prove an important reaction if we were to get serious about climate change, which, of course, we won't do. (Instead we'll get excited about trash written in the Guardian.)

I personally believe that the reformation of certain kinds of biomass is probably the only realistic means of removing carbon dioxide from the air. I've written, albeit peripherally, about these reactions in other places:

Better Chemistry, Better Biofuels? The Glycerol Glut, Solketal, and Other Floating Ideas

Since this blog post was written, a great deal more has been published about glycerol. I came across a very nice paper today on the subject while leafing through recent issues of one my favorite journals, this one: Hierarchical ZSM-5 Zeolite Synthesized by an Ultrasound-Assisted Method as a Long-Life Catalyst for Dehydration of Glycerol to Acrolein (Ind. Eng. Chem. Res., 2016, 55 (27), pp 7318–7327)

Uranium Catalysts for the Reduction and/or Chemical Coupling of Carbon Dioxide, Carbon Monoxide, and Nitrogen

In this blog post, I discussed (and produced a graph) of the Boudouard equilibrium.

I stand by my original comment to this useless appeal to hydrogen based wishful thinking. Anything that requires methane can hardly be "emissions free." In any case, I oppose the mining of all dangerous fossil fuels.

As another poster in this thread correctly pointed out, graphite is very unlikely to be stockpiled or even trucked to a "graphite dump." If no other use can be found for it, it will be oxidized to carbon dioxide and dumped in our favorite waste dump, the planetary atmosphere.

Thanks for your question. Have a nice week.