Tuesday, November 20, 2007

Hydrogen from biological sources

Sunrise in Cancun, Mexico

What's the most miraculous thing you can think of? What is the most amazing thing that exists on this planet? What just totally blows your mind about your existence? If you said "my existence," you totally got that question right.

Life is amazing, plain and simple. If you're unconvinced, Wiki "DNA" or "protein folding" or "hemoglobin" and try to make sense of it. The processes that are involved with living are just... incredible. English will fail in describing just how incredible they are so I'll stop stuttering and move on. The reason I'm on this tear is that I had a biochem test today and, with my regimen of chemistry lecture classes, I'm always torn between overworked and utterly fascinated. I guess that's how you know you picked the right major, ya?

We know so much about life and, yet, so little. What we do know is that, in it's present form and capacity, the earth can handle a whole ton of organisms without importing anything from anywhere. Well, there is one exception: the sun. Without the sun, we're toast. Actually, we're the opposite of toast but either way we're screwed. Solar radiation is pretty much the source and power for all life on the planet.

Sunset in La Jolla, California
Point being, the sun will be here while we're here and, when it's gone, we're gone too. While it's here, it's unlimited and we must find a better way to use it than we are doing at present. Solar power and all of it's subsets are THE way to energy independence for every country, state, and person on this planet. I've said it before and I'll say it again:

biological processes can solve virtually any problem. in particular, it can solve our energy problem

Here's just one reason why:

Researchers at Penn State University say they've developed a way to use bacteria to extract hydrogen from almost any biodegradable organic substance, from grass clippings to wastewater.

You always hear that hydrogen is the most abundant element on the planet. It is but not in the gas phase that we need it to use it for energy. Why? Because it just can't ever be that easy, can it? That and it is really energy dense so creating it costs energy. Thermodynamics says you can't create or destroy energy - one system uses it to do work on other systems and the energy just moves around. Anyways...

The main problem with a hydrogen economy as it stands (and, if I say, from a very pessimistic or simpleton mindset) is our current inability to get hydrogen out of the states it likes to be in (mostly bonded to carbon like in oils, tissue, hair, anything relating to life). Algae is currently being explored, now bacteria.
Logan and his research assistant Shaoan Cheng's method uses bacteria called exoelectrogens to break down acetic acid -- produced by fermenting cellulose, glucose or other biodegradable organic matter -- in a microbial electrolysis cell to create hydrogen.

You might, at this point, be asking "whathef..." What they're doing is taking cellulose (very abundant, non-digestible carbohydrate from plants) or any other organic material (something that contains carbon and hydrogen like your bod, anything you eat, anything that grows) and making acetic acid by fermenting it (letting it go bad). The little micro-organisms break it down and...
When bacteria consume the acid, electrons are transferred to a graphite anode. The bacteria also release protons -- hydrogen atoms stripped of electrons -- that are held in solution. As electrons are transferred to a platinum cathode, they combine with the protons and generate 0.3 volts of electricity. Adding another 0.2 volts creates hydrogen gas.

These bacteria are actually oxidizing (removing electrons [what electricity consists of]) the acid! Stuff happens and electricity is created. Boost that voltage with a little bit more and hydrogen gas is generated. Wow... Here is the big picture:
The researchers noted that the method produces up to 82 percent more energy than the electricity and biomass needed to produce it.

Keep that in mind... that is an important figure. The higher that percentage is, the better. Oil is probably 200-300% (total guess) while ethanol is under 10% and sometimes less.

Here is the Penn State announcement.


Anonymous said...

it's that kind of reverence and awe about the vast unknown and the complexities of this world that is so much bigger than we are (not just literally) that makes me wonder why so many scientists are atheists.

and yeah, the sun is such the obvious power source, right?

also, all this sciencey talk made me think of a video i watched recently on youtube about lemon batteries (lemon + penny + nail= power). talk about biodegradable.


Josh C said...

Scientists as atheists deserves a whole blog on its own, that's for sure. When you're studying the microworkings of the world, any position on its genesis, scientific or intelligent, has to be tentative.