How To Make Waste More Useful Using ... Bacteria?

Waste is polluting our planet. Bacteria can cause disease and spread death. Greenhouse gases can result in amplified global warming. Each by itself seems to result in nothing but doom. Let´s just mix them all together! The result, a possible solution to two of the biggest problems we may face in the future: waste, and global warming.

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What Is This Supposed Miracle I Am Speaking Of?

Imagine a world where waste can be turned into something useful. A process that may be able to turn this into reality is pyrolysis.
Now, imagine a world were greenhouse gases can be used for good. We are developing methods to fulfill that promise also.
Another great imagination: bacteria that do not cause disease, but help us to produce useful good for society, on environmentally sustainable term. Look no further.
Biotechnology and chemistry are a great team. Sadly, as a former mentor of mine (who runs a biotech startup) said, there is not enough technology in biotech. However, research has resulted in some very promising new approaches. Today I want to talk about the production of syngas from waste, and the production of useful chemicals by anaerobic fermentation of carbon monoxide and hydrogen gas, facilitated by our arch enemy, the microbes.

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How To Turn Waste Into Syngas?

Syngas is a mixture of carbon monoxide (CO), hydrogen (H2) and carbon dioxide (CO2). CO is toxic and CO2 is known to be a greenhouse gas.
Solid waste, biomass (waste from agriculture, wood, fallen leaves, etc.) can be turned into syngas by a process called pyrolysis (1). Pyrolysis is simply the production of biochar (very roughly biocoal), by heating up waste, without burning it (2). Due to exposure to very high temperature, the molecules in the waste undergo decomposition (they break into smaller molecules), resulting in biochar and syngas. Atoms form bonds, this is a well-known fact. These bonds have specific energies. By applying heat (in the form of very high temperatures) you supply energy to a molecule, overcoming the energy of the bonds and thus giving the atoms incentives to go their separate ways. If you hit just the right temperature, you can cause complex molecules to split up in a lot of smaller molecules. This is done in pyrolysis.

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Sadly, the conversion rates are not very high, but with new catalysts, it can be increased (1). In very crude term, we can turn waste into syngas by heating it up, while preventing it from burning.
But why should we bother about producing toxic greenhouse gases?

The Use of Syngas

Syngas has enormous value in the chemical industry. This paper demonstrates how to use syngas and a co-culture of two different bacteria strains to enhance the production of methane. This can be used as a fuel (methane is one of the main constituents of natural gas), or in the production of several other important molecules such as methanol.
Another way syngas can be used is in the production of ethanol, as shown in this article. Another study has demonstrated the same process, with an efficiency of 83% (3). Ethanol has long been used as a bio fuel and is also important in laboratory work. I have probably used 2-3 liters of ethanol within 6 days of laboratory work. It is very useful to dissolve certain materials and also important for cleaning laboratory equipment.
Syngas can also be used to form longer-chain hydrocarbons (4)
There are many other potential uses of syngas and its immediate products, as can be seen in this graphic.

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Outlook

By developing new catalysts, we will be able to make the conversion of waste to syngas more sustainable, both financially and environmentally. Scientists are also working on developing new catalysts that are able to facilitate the conversion of syngas into other useful products.
The fantastic thing about this method is, that we are able to convert something useless, something harmful, into products that can benefit the world. Furthermore, by making this process more efficient and cost-effective, scientists are creating financial incentives for large scale industries to adopt this method.
I am a nature enthusiast, and I love being outside. So I really have an interest in maintaining nature, so we can keep impressions like this alive.

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Thank you very much for reading my post about this promising technology. If you have any questions please leave them in the comments. Do you think we may be able to take this technology to the next level?
I would also love to hear your input, if you have some more sophisticated understanding of this. I am a biochemist and chemist, not a biotechnologist or engineer.

I really appreciate quality feedback. If I did something wrong, please let me know and I will adopt it in my next post. If you think I did something very well - I always appreciate encouragements!
If you liked this post, leave an upvote. Also you may want to check out my series on instrumentation, my series Genius and Madness or my Lab Chronicles, in which I write about my research to develop filters that filter hormones out of water.

As always,
Cheers @lesshorrible!