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Using Enzymes to Help Fight CO2 Build-Up
A reader writes to us: "There is a story in the New Scientist that details efforts to use enzymes that destroy ethanol as catalytic converters, turning noxious carbon dioxide into methanol. " The enzymes in question are actually those that are found in the liver - the same one that helps break down alcohol. Cool application of it, if this ever becomes reality.
Basically, they're advocating using CO2 as what amounts to a chemically-based energy storage unit. Methanol may not be the most human or environmentally friendly substance, but it IS easily convertable back into energy, stable and easy to transport, etc. I could see this technology being used (in conjunction with solar or other more convential power systems) as a method of extracting portable energy to fuel rovers and such on Mars, where there's an abundance of CO2 in the atmosphere waiting to be harnessed.
All very 'blue sky', of course. I'd expect that there's other fuel source methodologies that would be more efficient than this process too.
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rickf@transpect.SPAM-B-GONE.net (remove the SPAM-B-GONE bit)
"People will pay big bucks for the luxury of ignorance."
I'm going to be childish and quibble that vapour isn't really a gas. :)
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
Step 2: CHOOH
Step 3: CH2O
Step 4: CH3OH
I can't be the only person who noticed that the step from 1 to 2 added 2 hydrogens, step 2 to 3 deletes an oxygen, and step 4 adds 2 more hydrogens... without any mention of where these things are coming from and going to! I'm not a biochemist so I don't know anything about the chemistry of NADH, but a science article ought to at least explain how the equations are balanced.
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Time is Nature's way of keeping everything from happening at once... the bitch.
1) CO2 scrubber produces methanol
2) Methanol is used to provide more power to a fuel cell...
(Obviously, not in violation of the 2nd law of thermodynamics, just squeezing out a little more fuel efficiency..)
I *don't* know if this would be practical (i.e. use more energy to power the CO2 scrubber than the fuel cell would produce... That would be kind of pointless...)
coral reefs are much more important as carbon sinks.
That makes sense, since coral reefs build upon themselves, so the removed carbon is accumulated in lower levels of the reef. Trees, on the other hand, have a relatively fixed level (you do build up soil, but I doubt at the same rate), and as trees die they decompose and the CO2 gets released.
My favorite alternative energy generation technique is off-shore wind generators, as there's plenty of ocean room for them (even on the shelves), and they would provide residences for waterlife. It seems like they would also provide bases for coral reefs, at least in the right water conditions, making them even better environmentally.
Ooh, a sarcasm detector. Oh, that's a real useful invention.
Water vapor causes 98% of the Earth's greenhouse effect. Carbon dioxide gets called "major" because environmentalists love water and can't do anything about it. Imagine what the next ice age will do to the present environment.
There is a story in the New Scientist that details efforts to use enzymes that destroy ethanol as catalytic converters, turning noxious carbon dioxide into methanol.
Enzymes that destroy ethanol... noxious CO2 -> methanol...
So basically they're the kind of like me. I break down ethanol with my liver,
and then produce noxious methane (you know what i mean)
=D
On the other hand, if you made yourself an -edible- Silicon-based life form, it could be open-sauced. :)
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
Carbon Dioxide is not 'noxious', any more than our exhaled breaths are. The threat it represents is that of a greenhouse gas, effectively operating as a heat retainer for our planet.
Although, now that I think about it, some people's exhalations are pretty noxious... ;)
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rickf@transpect.SPAM-B-GONE.net (remove the SPAM-B-GONE bit)
"People will pay big bucks for the luxury of ignorance."
They go on about how great this is, and how you can cut down on the amount of C02 into the aptmosphere, and it sounds perfect. Until they get to the fact that you need a lot of electrons to make this work. Hess's law states that you can go through any pathway for a reaction, but that the amount of energy is the same in the end. This means that whatever you are burning to create this CO2 must release more energy than the ethanol that you are producing. Seems to me that ethanol releases a lot of energy when it burns. I want to know what type of fuel's CO2 they plan to convert.
By far the nastiest gasses are NO2 and SO2. These give you that icky brown and yellow smog, which you can see over many industrial cities and major roads during a temperature inversion. They are also the predominant gasses on Venus and are the primary cause of the hellhole nature of that world. They also contribute FAR more to the greenhouse effect than carbon dioxide.
Now, if the enzymes could do something useful with those, I'd be impressed. Clean up smog AND remove the greenhouse effect in one easy sweep. Anyone want to develop a sulpher-based life-form?
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
Back in 1994, there was much discussion on usenet about introducing a bill to outlaw internet usage while under the influence. My reaction was such an idea was absurd, but those people seemed serious enough to try and push for it. Laughable now, but you should see some of the laws on the books.
Oh yes, drunken surfing! Sure, what you see when drunk might cause your eyes to bug out, but the only thing that might crash is ill written code or operating system. Back in the old days when the pooter crashed, one could often see pretty colored characters dancing across the screen. And that was fun.
Coding while drunk often brings out the most lines of code and arguably the most productivity. I once wrote 200 lines of daring assembly language for a Z80 GUI with mouse and keyboard support on such a binge. The rest of the weekend was spent just to get the damn thing to work!
Methanol is not ethanol. Methanol is toxic when drunk, toxic when the vapor is breathed, toxic when absorbed through the intact skin, and really bad news if you squirt a couple of drops in your eye.
Don't forget 100% miscible with water. Spill the stuff and any ground water or reservoir it gets into is going to be poisonous....
Methanol is a perfectly fine chemical, as long as you take good care of it. As a large scale fuel, its toxicity makes it Right Straight Out.
Ideally, they could do the same thing to produce ethanol, which is essentially harmless. Unfortunately, that attracts the attention of Mister Tax Man.
..run a methane powered fuel cell battery (as referenced in /. recently, developed by Motorola I believe). The components of it could be build into the enzyme holding structure, and could react with just enough of the methane to recycle an appreciable amount of the NADH.
Someone run with this idea.. please..
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Sean Dunn
DigitalAnvil.com
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Time is Nature's way of keeping everything from happening at once... the bitch.
Yes, I recognize the satire of the posting I'm replying to.
No, Earth is not covered and is not a closed system. The top of our atmosphere leaks, and we're venting gases just as Mars did. Fortunately we've got more gases, have greater gravity so leak more slowly, and might be reabsorbing more snowballs (if we are indeed getting hit by ice from space...some of that would be our own leakage). Warmer gases will expand the atmosphere and more will leak away more quickly (in addition to dragging more on Mir). Not a problem as long as we've got enough water to keep making enough water vapor to keep us above the freezing point (where we'd be without the water vapor greenhouse).
Not to mention that global warming causes ocean levels to fall and not rise. This is the biggest misconception they try to pull over on you. take a glass with 3 or so ice cubes and mark the water level. cover it and let it set a few hours. When you come back you'll find the level has sunk. "Well gee Mr. Wizard, why is that?" "well Timmy,(or Tommy or whichever one he didn't blow up last week) that is because water expands when it freezes.
But like the above post states the greenhouse effect is what keeps us alive!
that and they keep saying global waming over and over. Last year was the 15th warmest on record for the 21st century. If GW were a serious problem, the last 50 years would be the warmest in a slow progression upwards.
Besides, I think the article is likely incorrect. CO2 is not noxious, CO is.
Lowmag.net
Shessh!
Last time I checked, Animals had a nice symbiotic relationship, we breath O2, and exhale CO2, Plants breath the CO2 and "exhale" O2...
Until we invented automobiles that burn hydrocarbons...
Our lovely vehicles spew out Carbon Monoxide(CO). Thisis both deadly to plants and animals.
Yeah, this article is nice, but it's not the levels of CO2 that we should be trying to reduce from our cars, it's the levels of CO. (Of course, reducing CO2 would help reduce the greenhouse effect, but that's a different story..)
H.
Suppose you have a fuel-cell hybrid car. The fuel cells run at high pressure, so you can store the CO2 in tanks (perhaps along with the water, all dissolved as soda water). You can either dump the soda-water and buy more methanol (expensive, perhaps, if carbon taxes are imposed) OR you can hook up to the wind genny, solar panel or wave-power machine somewhere and use the CO2/NADH reaction to regenerate methanol and oxygen from the CO2 and H2O. This effectively puts the exhaust back into the fuel tank. You wouldn't necessarily have to do the regeneration in the car; you could dump the soda water into a tank at home or a station and regenerate it there.
This is equivalent to a battery-powered car, but without any effective daily-range limitation and "recharging time" of a few minutes.
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Time is Nature's way of keeping everything from happening at once... the bitch.
CO2, on the other hand, is food for plants.
Only during the daytime. CO2 is used in conjuction with sunlight to produce O2+energy. During nighttime, plants consume oxygen just the same as you and I.
The above equation may be greatly overgeneralized but it's been quite some years since my Biology classes.
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Time is Nature's way of keeping everything from happening at once... the bitch.
Besides, methanol's only uses are as a fuel and as a raw material for making other compounds. When you burn or catalyze the Methanol as fuel, you get the CO2 back again, and when those other compounds are eventually consumed or destroyed, you get the CO2 back again (and other noxious compounds, by the way).
Now, I'm no scientist, so don't yell at me if i get something wrong, here. But wouldn't that mean that if we found a way use that methanol to power whatever it was was we were getting CO2 from in the first place, that we could just use it over and over again?
-- Dr. E --
The article doesn't mention chemical H2, it mentions NADH. I'm assuming that NADH can be regenerated at the cathode of an electrolysis cell, but the article (and your description) still leave me in the dark as to the exact role played by NADH and how it is altered in the process.
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Time is Nature's way of keeping everything from happening at once... the bitch.
CO2 + H20 <==> H2CO3
(occurs without catalysis, but can be sped up by carbonic anhydrase)
H2CO3 + NADH + H+ <==> HCOOH + NAD+ + H2O
(catalyzed by formate dehydrogenase)
HCOOH + NADH + H+ <==> HCHO + NAD+ + H2O
(catalyzed by formaldehyde dehydrogenase)
HCHO + NADH + H+ <==> CH3OH + NAD+
(catalyzed by alcohol dehydrogenase)
Net reaction: CO2 + 3NADH + 3H+ <==> CH3OH + 3NAD+ + H2O
I think that's balanced. Biochemists are often lax about mentioning hydrogen ions and water molecules in a reaction because it's generally assumed that they're present in abundance in biological conditions.
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Time is Nature's way of keeping everything from happening at once... the bitch.
THIS is the missing chemistry from the New Scientist article! Thank you, sir, for the enlightenment. (Someone ought to moderate the parent post up.)
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Time is Nature's way of keeping everything from happening at once... the bitch.
- Precipitate carbonates (calcium, magnesium) from seawater.
- Roast carbonates to oxides, capture CO2.
- Dump any undesired oxides back into the ocean, raising the pH, converting bicarbonate ion to carbonate ion, and helping absorb more CO2. (MgO may be worth saving for conversion to metal.)
- Convert CO2 to CH4 or MeOH using whatever process is desirable. Use as fuel elsewhere.
If you have enough cheap energy, this might actually be feasible.--
Time is Nature's way of keeping everything from happening at once... the bitch.
Actually some of those polyps are quite brave! They leap into the water, and hope that the currents will take them into a new area suitable for growth.
Since photosynthesis removes CO2 from the atmosphere, The Iron Solution to the global warming problem proposes to radically expand photosynthesis on the planet by fertilizing high nitrogen, low phytoplankton regions of the ocean with the element that limits phytoplankton growth in those regions: iron.
A side benefit of this sort of agriculture is that it would tend to lessen agricultural demand for land-based ecosystems that are currently being slashed and burned for agricultural production, such as rain-forests. Phytoplankton is at the base of the food chain for high protein organisms like fish. People would have to get used to eating less pasta and more halibut -- a small price to pay for the salvation of millions of species, except maybe for Italians.
Seastead this.
Actually to anyone with a biochemistry or organic chemistry background the answer is obvious. The oxygen comes from the water in which the rxn takes place (actually probably in a step 0 where C02 + H20 -> CO3H2 which is carbonic acid). The reducing potential to take the oxygen off comes from NADH being oxidized to NAD+. The actual hydrogen atoms/ions coming from NADH and/or water. Typically the statement that NADH is a co-factor in the rxn is enough to make the above clear to the audience of the New Scientist.
Up until 1750 it was the pattern I'd expect to see in a steady system, more or less steady with random variations about the mean.
Unless you can give a reasonable explination for a steady increase since 1750 (When the industrial revolution dramatically increased the amount of fossil fuels being burnt), your theory doesn't hold up.
Now if they will just create a enzyme that will clean my bathroom.
If you want to kill a plant, then putting it in a O2 less atmosphere will do it much quicker than a CO2 less atmosphere, the difference between suffocating than starving.
The entire article is about Carbon Dioxide, yet in their graphic of the chemical reaction, they show a nuclear power plant in the background as the generator spitting out "greenhouse gasses"...
Maybe I'm just picky because I grew up 3 miles from the Limerick Nuclear plant in southeast PA, and was forced to learn about it in HS, or maybe its because I work for a utility company. ;)
-- Scott
...when I first learned about the wonders of hydro-electrolysis, and found out about the perfect closed fuel circle that could result from the simple seperation of hydrogen and oxygen in water.
My mind spun with all the things you could use it for. Well, I'm a little older, a little less enthusiastic, and maybe a little more efficient. Now I know it's just another way to move energy around, like batteries or gasoline.
If it's as efficient as they make out, combined with the new cheap methanol fuel cells, this could be the clean, portable energy solution of the next century. It has every advantage of the hydrogen energy system (well, maybe it loses a little in simplicity of generation), plus the extremely important bonus of how easy it is to move methanol around. There are plenty of other ways to get methanol, too. Forget solar power plants: fermentation of vegetable matter into methanol is simple; you could fuel your cell phone out of your compost bin.
Just think of what we can do with all that formaldehyde.
O_o
Tough luck:
1. Thermodynamics say that in order to convert CO2 into CH3OH you have to use quite a lot of energy. So whatever you burn like that will be bloody inefficient
2. The only productive thing you can actually do with the CH3OH is burn it so back to CO2. It can be converted into some plastics and stuff but the overall demand for such material is not high to satisfy a massive generation of CH3OH.
3. Better stop cutting the brazilian forests. I actually check the labels on all the stuff I buy and try not to buy anything that is not:
3.1. Made of recycled paper (this technology is dirty as well but still better than nothing).
3.2. Made out of planted forests in scandinavia or somehewhere else where they plant at least as much as they cut.
In btw: these labels are almost standard on anything sold in the EU.
Baker's Law: Misery no longer loves company. Nowadays it insists on it
http://www.sigsegv.cx/
Can someone please change em so they make ethanol? Please? (Not that I mind the taste of methanol, it just makes you go blind a lot quicker, and if that happens I can't find my glass).
We all know our bodies don't need any methanol floating around in them, but I can't help but wonder whether this is another step along the way to finding the holy grail of alcohol metabolism: a pill that speeds up the process of alcohol metabolism. The financial reprocussions would be enormous both for the manufacturer and for society at large which would benefit from increased productivity with saying good bye to hangovers. On the other hand, alcohol consumption would skyrocket and we'd become an even greater society of alcoholics than we currently are, not to mention all the idiots who would still manage to induce alcohol poisoning in themselves.
But just look at how societies have always grown up around the simple fact that it takes hours for people to sober up, and imagine a world without that. My cynical mind wonders what hell might replace it.
"If one is really a superior person, the fact is likely to leak out without too much assistance" -- John Andrew Holmes
In your .sig:
>Important Proir cases effecting DECSS, a must read
affecting, not effecting is correct here...
(this particular mistake is one of my pet peeves - really makes people sound/look uneducated. Almost as bad as "your/you're" problems)
"It's tough to be bilingual when you get hit in the head."
Actually, this is part truth and part myth...
Plants do produce much less O2 during the nighttime, but they do not consume it - they do actually continue the process. Without the added energy of the sun/light source they can only keep this up for so long, but if you check out a book that does a good in depth analysis of photosynthesis and the Kreb's cycle, you should be able to get all of the info there.
Though it used to be common practice in hospitals to remove plants from the patients rooms at night for the very reason you mention - the newer, more accurate research has led to the repeal of these actions.
"It's tough to be bilingual when you get hit in the head."
New Scientist does not even bother captioning most of their pictures, which is probably appropriate because few of them are very relevant to the stories in which they are placed. It is not even in the league of Scientific American in that respect. On the other hand, it is a weekly, and it is fairly thick. I've subscribed to it and found it expensive (in US$) but about as worthwhile for the money as Science News (burden of glitz outweighed by volume of coverage).
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Time is Nature's way of keeping everything from happening at once... the bitch.
The big-assed coal plant doesn't matter 'cause you're just making car fuel anyway? And what are you going to do with that car fuel -- drink it? No, you're going to burn it, releasing CO2 back into the air. So basically, you've managed to engineer it so cars can run on coal via an intermediate process, but you've done nothing to reduce the net CO2 emissions. That doesn't have too many useful applications.
As for your second idea, that's pretty much how rocket propulsion is done, and you can imagine that what's appropriate for rockets is perhaps not appropriate for cars, and in any event it's expensive and still requires a "big-assed" power plant to provide the electricity for the original electrolysis, because your idea of a closed internal combustion engine by definition couldn't do any work on the outside world (which is what driving cars is all about). Heck, you wouldn't even be able to idle the damn thing, since there's still some friction and you wouldn't get 100% yield if you tried.
Maybe you should patent it anyway, since the USPTO seems to deserve patents like that.
"If one is really a superior person, the fact is likely to leak out without too much assistance" -- John Andrew Holmes
So you can have solar panals generate the electricity for these reactions. Who cares if you need lots of power, the sun supplies more than enough.
This produces methanol which you can then use to power those methanol, air breathing fuel cells that are in developement.
The fuel cells actually burn cleaner than Internal Compustion Engines so you get less nasties in the emmisions, and of course you take the CO2 and start it all over again.
Of course you can also burn it in Gas turbines, which have a nice clean exhaust as well.
"Because we are not employing at entry level, offshoring will kill our industry stone dead."
Carbon dioxide is a major contributor to the global warming effect. For that reason, a lot of people equate CO2 with global warming. There are, of course, a lot of other atmospheric effects that effect total heat absorbtion and retention, but bringing up details like that tend to confuse people. Easier for the media to use simple words, like "Too much CO2 = Global Warming. Global Warming BAD!" I always thought that a majority of the worlds CO2 gets fixed into Limestone, but it's been a while since I've done geology stuffies. Of course, the difference between calcification and trees is that trees spit out what we need as fast as they take up what we spit out. Gotta love the symmetry of that. Not to mention that most people have had personal contact with trees (skiiers especially ;) whereas few people will have the luxury of being up close and personal to, say, the great barrier reef outside of a Jacques Cousteau video rerun. BTW, you CAN use <A HREF=...> tags in your comments, like on that Bad Greenhouse Link.
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rickf@transpect.SPAM-B-GONE.net (remove the SPAM-B-GONE bit)
"People will pay big bucks for the luxury of ignorance."
Okay, nice responses on water ice. But you're forgetting evaporation of frozen methane can make sea levels go down when the water warms. Of course, then we've got a bunch of methane in the air too. Got all that in your climate models?
Sulphur-munching bacteria. Just what we need to seed Venus with. Convert some of sulphur and carbon in the atmosphere into piles of bacteria...odd soil, but better than what they've got now.
We'll be needing all the carbon dioxide in the air we can get our hands on soon, so that nanotech can built all our gadgets and mansions and personal trans-continental pipelines for us.
Leave all that automotive carbon alone --- it's our future feedstock!
"The question of whether machines can think is no more interesting than [] whether submarines can swim" - Dijkstra
This is a joke, right? I mean, no one could be so stupid as to think that changing massive quantities of comparatively harmless CO2 into highly toxic methanol is desirable on a large scale.
Methanol is not ethanol. Methanol is toxic when drunk, toxic when the vapor is breathed, toxic when absorbed through the intact skin, and really bad news if you squirt a couple of drops in your eye.
Besides, methanol's only uses are as a fuel and as a raw material for making other compounds. When you burn or catalyze the Methanol as fuel, you get the CO2 back again, and when those other compounds are eventually consumed or destroyed, you get the CO2 back again (and other noxious compounds, by the way).
CO2, on the other hand, is food for plants. If you "cleaned" the atmosphere entirely of CO2, all plants would die, no more O2 would be produced, and eventually all O2 would be consumed and all animals would die. Yes, we are animals, and we would die too.
The New Scientist article is baffling because it seems to have things backwards. Our livers (in the unhappy event anyone is foolish enough to consume methanol - not ethanol) in fact convert methanol into formaldehyde and formic acid, not the other way round. It is this formaldehyde and formic acid that account for the toxic effects - notably permanent blindness and destruction of the nervous system and cerebral cortex (not real fun). I know the article waves its hands and says, oh, the process is reversible. Maybe...
Just go to hospital, first aid department. Wait til you're first in line. and have some methanol handy...
Nurse: what's the matter sir?
you: I'm about to go blind because of methanol poisoning.
(Now is the time to drink some methanol)
The usual way to cure methanol poisoning: saturation with ethanol. Up to the point of getting poisoned by the ethanol.
Disclaimer: If you actually try this you're pretty stupid, so don't come complaining to me (if you can find me on sound and smell)
//rdj
No one can understand the truth until he drinks of coffee's frothy goodness.
--Sheikh Abd-Al-Kadir, 1587