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update (Sept. 2018): Here is a bit of news that someone might be inclined to cite in a "No, not yet, but..." answer.

NASA has announced a CO2 conversion challenge!

Get out of your element! Convert CO2 into molecules to power bio-manufacturing in space.

Convert CO2 to Glucose:

Help us discover ways to develop novel synthesis technologies that use carbon dioxide (CO2) as the sole carbon source to generate molecules that can be used to manufacture a variety of products, including "substrates" for use in microbial bioreactors.

Because CO2 is readily abundant within the Martian atmosphere, such technologies will translate into in-situ manufacturing of products to enable humans to live and thrive on the planet, and also be implemented on Earth by using both waste and atmospheric CO2 as a resource.

It looks like this will be a multi-year project.

original question (Mar. 2017):

A large mass fraction of foodstuff a person would need on a long trip (for example, in space or otherwise not on Earth) would come from its caloric (energy) value. Scenarios have been explored for decades to use solar photovoltaic (or other electric) power to generate light to grow plants locally for food. Light provides energy for photosynthesis which combines $\ce{CO2}$ and $\ce{H2O}$ and makes glucose, (later converted to and stored as starch) which then provides caloric value to food.

$$\ce{6CO2(g) + 6H2O(l) -> C6H12O6(s) + 6O2(g)}$$

I'd like to know if a purely non-life based self-contained chemical process has been developed or is at least close to continuously converting $\ce{CO2}$ and $\ce{H2O}$ to glucose, using electricity directly, or electrically generated light.

By "non-life based" I mean it's not a bioreactor based on living cells. It could certainly use processes that are similar to those used in organisms.

The process would have to be potentially able to run stand-alone with minimum consumables, in the same sense of the term "process" as is mean for the Haber Process.

I am not asking if you think it could be done, but if there is a way that it could be done, based on well-documented research towards implementing complete Artificial Photosynthesis using light or electricity, not just a demonstration where a laboratory technician regularly adds separately prepared reagents and precursors for each step.

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    $\begingroup$ @Mithoron No, those are not really related at all. I've specified starting with $\ce{CO2}$ and $\ce{H2O}$, not cellulose, and ending up with glucose, not methane. $\endgroup$
    – uhoh
    Commented Mar 19, 2017 at 17:52
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    $\begingroup$ It is clearly possible that some chemical process can do this (after all plants do it) but the complexity of the processes used in photosynthesis suggests it is very hard to do it. Possibly alternative routes might be easier but using elements not commonly available to plants (heavier, rare metal catalysts, for example). $\endgroup$
    – matt_black
    Commented Sep 4, 2018 at 10:58
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    $\begingroup$ If I remember the figure quoted to me by Dan Nocera, plants rebuild photosystem II roughly once every 20 minutes. If I remembered that right, it gives a sense for how messy this process is and therefore, complex from a chemical engineering perspective. $\endgroup$
    – Zhe
    Commented Feb 21, 2019 at 16:27
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    $\begingroup$ I was thinking of this too! I think this is a good candidate for both X Prizes - making CO2 extraction valuable, and removing CO2 from the atmosphere! $\endgroup$
    – Jonathan
    Commented Mar 1, 2021 at 2:47
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    $\begingroup$ @Jonathan I don't have any real money to contribute towards an X Prize, but I'll add a nice bounty to an answer that solves these problems :-) $\endgroup$
    – uhoh
    Commented Mar 1, 2021 at 2:49

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Popular research these days for CO2 fixation involves the following enzymes with associated conversion rate:

  • RuBisCO - 10 molecules/sec
  • ECR(Enoxyl-CoA carboxylase/reductase) - 80 molecules/sec

The major noncarbohydrate precursors are lactate, amino acids, and glycerol.

Here are some links to current research:

Some topics for research:

  • Gluconeogenesis
  • Formose reaction
  • Calvin cycle (absence of light)
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    $\begingroup$ Thanks! This is the type of answer that I was hoping for. The whole synthetic process (CO2 to sugar via electricity or light) hasn't been developed, but you have highlighted work on several key steps along the way. $\endgroup$
    – uhoh
    Commented Nov 3, 2020 at 5:21
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    $\begingroup$ Turns out I was born a bit late and most of the ice sheet has melted; am working on a similar project with a different mission than providing sustenance on space missions $\endgroup$
    – Zimba
    Commented Nov 5, 2020 at 6:26

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