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Methane to hydrogen and gasoline?

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Enthalpy:
Hello everyone and everybody!

Commercial hydrogen is presently made from methane and water vapour, which outputs hydrogen and carbon monoxide, possibly dioxide in a second step
https://en.wikipedia.org/wiki/Steam_reforming
which all sorts of naysayers take as an argument against hydrogen-based transports: "releases dioxide too". It's not even so wrong.

Could it be done better?

By some sort of pyrolysis maybe, obtain H2 and a spectrum of CnH2n as a feed for valuable fuel components, for instance for alkylates to blend gasoline?

Cars would still emit dioxide when burning gasoline obtained from natural gas, as much as when gasoline derives from oil, but we would have run in addition planes, trains and cars on hydrogen
http://www.scienceforums.net/topic/73798-quick-electric-machines/?do=findComment&comment=738806
with no more dioxide emissions, and bought natural gas cheaper than oil.

Or do the same with C3 and C4 fractions. These are commonly torched at the well as they are too cheap to transport, but if a refinery transforms them, it would pay the tanker.

My understanding is that as long as crude oil is affordable, CO2 emissions are for free, and hydrogen is a marginal commodity, steam reforming is the economic answer. But time may change this situation.

So: could you imagine such a process? Ideas, suggestions, proposals, guidelines, fantasy?

Enthalpy:
How easy or difficult do you suppose it is?

Like: heat methane over some catalyst, freeze everything, sort out H2 and C2H4 from remaining CH4, process C2H4 further?

Enthalpy:
The desire I expressed is long identified and routes investigated. Keywords:
nonoxidative conversion of methane
Yes, I could have begun with that.

The oxidative routes couple carbons but results in some carbon oxides as well, while nonoxidative conversion seeks the higher hydrocarbons without oxides. The usual goal is "valuable chemicals", understand less cheap than natural gas, especially C2Hn, rather than hydrogen and additives for gasoline.

For instance Xiaoguang Guo et al used a catalyst of iron in silica
http://science.sciencemag.org/content/344/6184/616.full
to obtain ethylene, benzene and naphthalene without coke. Aromatics are presently an additive to gasoline but are unhealthy; more hydrogen in the feed squeezes the proportion of acetylene and aromatics, so ethylene and ethane would make most of the output.

Or Yang Xiao and Arvind Varma used Pt-Bi on zeolite (how expensive?)
https://pubs.acs.org/doi/abs/10.1021/acscatal.8b00156?src=recsys&journalCode=accacs
to convert >90% of carbon atoms to C2Hn.

Heat being so cheap, maybe the conversion can live without a catalyst, if enough hydrogen is present and the products are separated early to stop the reaction at C2Hn? If the reaction and the separation are quick enough, a low conversion per pass is acceptable.

zarhym:
My boss once talked about another way to convert methane into liquid form. He was talking about methanol. He suggested that by photolysis of ozone the triplet oxygen atom can be used as the oxidizing reagent to convert methane into methanol. I guess this can be done with flow chemistry.

However, mixing methane and oxygen is not a safe idea. A single spark could be devastating.

BobfromNC:
There are ways to do what you describe, but the challenge is all in economics.    It is possible to burn natural gas as it comes from the ground, without any complex factories or much technology.   In order to reform it to H2 and other alkanes, it would require an expensive plant, likely some precious metals and strong acids, and then you have to purify, store and sell the multiple products to different groups.  That all costs a lot of money, but the laws of thermodynamics show that you will get less energy out of the final products than went in, so you have to make products that have a high value.  With coal, natural gas, and oil being cheap, there is almost no one willing to invest billions in building facilities to reform one fuel into another, when it is already plentiful.   

I have seen companies spend billions on projects like that, biofuels, nuclear power, coal liquification, MTBE, and a host of other technologies in the last few years, but only a few have survived and every made any money, mostly the ones that either got government money, tax breaks, or some requirement that they have to be used.   So unless you have a few billion dollars to spend, or a lobbyist working for you, I doubt that this type of plant will happen in a large scale.    It might one day make sense to just cleave water into oxygen and hydrogen on a larger scale, but that does not compare favorably to just using the same source of power directly, such as solar thermal or PV systems, which don't require hydrogen storage or transport.

The simpler the system, often, the more efficient and less expensive.   The best way to "do things better" to me is to just not waste as much power as we tend to in the first place.  No source of power is as cheap and efficient as not using as much in the first place.   Use LED lights, higher efficiency devices, and insulate your house, and we can cut power use in the US by 50% easily.   I have seen it done, but so few are willing to spend the little up front money to do it, even though most efficiency projects pay off within a few years.

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