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Biochemical Reaction Catalysing Solar Trap

  1. Jan 12, 2009 #1
    I was thinking about an alternative way to harness solar energy there after reading a bit about photosynthesis. So these antennae pigments which chlorophyll is composed of trap solar energy and direct it so that it can be used to catalyse chemical reactions if I'm not mistaken. Wouldn't there exist substances that we can use to catalyse chemical reactions necessary for making fuels and other useful substances?

    I haven't got any specific reactions in mind since I was just thinking about how it would be possible to setup a large scale biochemical solar trap geared towards catalysing chemical reactions.
  2. jcsd
  3. Jan 12, 2009 #2
    One of my good friends is really big into photosynthesis and "synthetic photosynthesis", so he's been keeping me up to date on the latest breakthroughs. You're pretty close, but a little mixed up (though I'm not an expert either by any means). Most of the latest researching had been focusing on the catalysts plants use to split water, which happens to be based on manganese is I remember right. Many people hope that if this one step of photosynthesis could be isolated and removed from the rest of the system then we might be able to use it to produce cheap hydrogen with which to fuel a new green hydrogen economy.

    Getting to the point though, light isn't the catalyst. Light just provides all the energy to make things happen. The catalysts are parts of proteins (I think). If you're intesrets in doing a home experiment to split water the way that plants do I think you can do a simple extraction with spinach leaves and acetone. Google the terms "spinach" and "photosynthesis" and you should be able to find tons of articles on this type of research.

    Also, we already use catalysts to produce fuel. When crude oil is refined a process called catalytic cracking is used to increase the percentage yield of gasoline. Currently it employs a zeolite based catalyst which breaks apart the heavier chain hydrocarbons thus increasing the relative amount of lighter products.

    I don't feel like I really answered your question, but I hope I've still helped somehow.
  4. Jan 13, 2009 #3


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    In order for a chemical reaction to occur, it must meet two criteria: 1) the reaction must be thermodynamically favorable, and 2) the reaction must be kinetically favorable. The conversion of carbon dioxide into glucose is normally a very thermodynamically unfavorable process (the reverse reaction, burning glucose, releases a lot of energy). In photosynthesis, the energy from light gives the reaction enough extra energy so that the reactions are now thermodynamically favorable.

    The second criteria is where catalysts come in. Normally, the reactions of photosynthesis occur very slowly. You could take carbon dioxide and water, and shine light on them, but nothing would occur even though all of the ingredients are there. To speed up the reaction and make it occur on a reasonable time scale, nature has evolved enzymes (biological catalysts) to help along the reactions.

    As for using light to power reactions, there are a number of reactions that are commonly used in organic chemistry labs that are powered by light. It is very common for light energy to be used to add chlorine or bromine atoms to an organic compound. Unfortunately, the CFCs use similar mechanisms to harvest the energy of light to promote the destruction of ozone in the upper atmosphere.
  5. Jan 14, 2009 #4
    I have a question. does research like this fall under Biochemistry & Biotechnology?

    Also I was wondering, since the mitochondria in our cells produce protons which are trapped in the matrix of the organelle, couldn't we use a similar process to produce cheap Hydrogen?
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