Author Options:

CO2 hydrogenation (CO2 + hydrogen = methanol) how to ? Answered

I am wondering if methanol production (as a byproduct of CO2 and hydrogen) would be possible as diy project  .
I have been reading about CO2 hydrogenation that (as topic mentioned) would lead to methanol production.
Methanol would be easier to store than hydrogen ,no needing special equipment (refrigerated containers ).
Anyone familiar with this ?
One of the patents available:


The forums are retiring in 2021 and are now closed for new topics and comments.

9 years ago

In general, making synthetic hydrocarbons is out of the reach of the average hobbyist. Making synthetic hydrocarbons by chemical means usually requires very high temperature, very high pressure, exotic metal catalysts, fancy gas containment apparatus or several of the above.  Synthesising high-energy hydrocarbon fuels is one of the holy grails of renewable energy because it would solve the problem of solar panels and wind turbines only intermittently producing electricity, not to mention replacing fossil oil as a transport fuel.

The Fischer-Tropsch process (http://en.wikipedia.org/wiki/Fischer-Tropsch) is a related reaction, which converts hydrogen and carbon monoxide into methane (natural gas).  This is comparatively mild for an industrial process and is still done at several hundred degrees above ambient at a pressure of many atmospheres.

If you want to make a liquid fuel from carbon dioxide and water, try adding yeast to sugar water :) (bear in mind that to be flammable you will have to distil the result, which is quite possibly illegal where you are)


Reply 9 years ago

Page 8 of this very informative paper (Google Docs web view here) summarises the conditions used for industrial synthesis of methanol:

• Catalyst : CuO(60-70%)- ZnO(20-30%) –Al2O3 (5-
15%)or Cr2O3 (5-15%)
• Temp 220oC-300oC
• Pressure 50-100Atm (5-10MPa)
• Composition of the feed 59 -74% H2 27- 15% CO
8% CO2 3%CH4
• Conversion of CO to methanol per pass is normally
16– 40 %.
• H2 : CO ratio of 2.17.

In short, to perform this reaction you need a super-high-pressure hot oven filled with assorted metal oxides, recirculating a mixture of about 6 parts hydrogen to 2 parts carbon monoxide to 1 part carbon dioxide.  This gas mixture usually comes from natural gas, so the process isn't great for producing fuel with.

OTOH, nature is on top of the problem and provides ways for us to make both alcohols and methane by feeding plant matter to micro-organisms.


Reply 9 years ago

That paper (http://www.ics.trieste.it/media/139813/df6496.pdf ) provides an informative outlook for a number of industrial reactors (pg.19 to 73) for methanol production .
Problem is that their target is 7000 tons/day methanol production which is well above home use needs.
Maybe those info could be compared to academic reactors layout like those in this paper (pg.31 .. and pg.92 ..) :
having considered that home production isn't bounded by market competitive production prices .
Aving said that ,all this chem dialect isn't my dialy bread .
I agree with you about biogas being a more than valid alternative .
At the moment I am considering methanol as a wind turbine off the grid energy storage solution.
Plus I am intrigued by the CO2 being used in methanol production , which would lead ,apparently , to a greener process.
As for syngas feeding for reactor , I wonder if naudin bingo fuel reactor could be a possible candidate :
I am opened to alternative suggestions .


Reply 9 years ago

I suspect the problem isn't in building one of those reactors, it's running it.  I'm sure a well-equipped backyard engineer could build a vessel that would take 35 bar and 250 degrees, but where do you get a supply of 99.99% pure carbon dioxide to run it with?  If this reaction ran on atmospheric concentrations of CO2 I'm sure it would attract a lot more attention, but as it is it's only really suited to an industrial-scale process because of the feed requirements.

Again, sorry to sound like a broken record but for conversion of energy and atmospheric CO2 to energy-rich hydrocarbons, plant life has had about a billion years longer to work on the problem than us :)  I think that synthesis of fuels from renewable electricity/sunlight will become a major part of our energy infrastructure and as such I'd love to see every possible route explored, but I suspect this type of reaction benefits more from well-equipped chemistry labs than hobbyists.