Tobi Fadiran's List: Independent Research

• has become a global problem. Internationalization of industrial and social activities has given rise to problems such as global warming, desertification, and acid deposition. T
• has become a global problem. Internationalization of industrial and social activities has given rise to problems such as global warming, desertification, and acid deposition. T

• there is likely insufficient waste biomass to sustain a global hydrogen economy, this form of renewable energy production may help offset the substantial costs of wastewater treatment as well as provide a contribution to nations able to harness hydrogen as an energy source."
• "This MFC process is not limited to using only carbohydrate-based biomass for hydrogen production
• "Basically, we use the same microbial fuel cell we developed to clean wastewater and produce electricity. However, to produce hydrogen, we keep oxygen out of the MFC and add a small amount of power into the system."
• Environmental engineers at Pennsylvania State University and a scientist from Ion Power have developed a process that enables bacteria to coax four-times as much hydrogen directly out of biomass than can be generated typically by fermentation alone. The researchers are using an electrically assisted microbial fuel cell (MFC) that does not require oxygen.
• Environmental engineers at Pennsylvania State University and a scientist from Ion Power have developed a process that enables bacteria to coax four-times as much hydrogen directly out of biomass than can be generated typically by fermentation alone. The researchers are using an electrically assisted microbial fuel cell (MFC) that does not require oxygen.
• Environmental engineers at Pennsylvania State University and a scientist from Ion Power have developed a process that enables bacteria to coax four-times as much hydrogen directly out of biomass than can be generated typically by fermentation alone. The researchers are using an electrically assisted microbial fuel cell (MFC) that does not require oxygen.
• Environmental engineers at Pennsylvania State University and a scientist from Ion Power have developed a process that enables bacteria to coax four-times as much hydrogen directly out of biomass than can be generated typically by fermentation alone. The researchers are using an electrically assisted microbial fuel cell (MFC) that does not require oxygen.
• Environmental engineers at Pennsylvania State University and a scientist from Ion Power have developed a process that enables bacteria to coax four-times as much hydrogen directly out of biomass than can be generated typically by fermentation alone. The researchers are using an electrically assisted microbial fuel cell (MFC) that does not require oxygen.
• Environmental engineers at Pennsylvania State University and a scientist from Ion Power have developed a process that enables bacteria to coax four-times as much hydrogen directly out of biomass than can be generated typically by fermentation alone. The researchers are using an electrically assisted microbial fuel cell (MFC) that does not require oxygen.

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• Concerns abound about storage, fueling stations, and the transition from now to then. In addition, some people worry that even though hydrogen burns clean, it might be made from the same old CO2-generating natural gas and oil we are using now. But the work that researchers have been doing for years on biologically generated hydrogen is starting to get noticed, and it might be just the ticket.
• if we are ever going to completely transition, we need to solve the problem of massive amounts of cheap hydrogen made from renewable sources.
• Proposals for creating hydrogen from solar electricity, geothermal sources, and wind power are all enticing, and will definitely be a part of the process. But we wonder how these methods can expand to fill the 68% of energy usage gap left by oil and coal in the US
• 68% of energy usage gap left by oil and coal in the US
• While new species are being found all the time, the genera has been researched for at least 15 years and has considerable success under its belt.
• To generate biotic hydrogen, there are two main methods. Both involve collecting energy from the sun in plants, and then converting that stored plant energy into hydrogen with a bacteria.
  
• The first, and most successful method to date, involves feeding special bacteria a diet of plant starches.
• In some situations, a gas which is up to 43 percent hydrogen can be extracted continuously from the vats.
• Rather than using an external plant to generate starch, a symbiotic system involving algae and bacteria are used.
• a symbiotic system involving algae and bacteria are used.
• The algae uses sunlight, water and carbon dioxide to make a hydrocarbon molecule, which is passed to the bacteria, which "eats" it, freeing carbon dioxide and hydrogen. The CO2 goes back to the algae to be used again, while the hydrogen is collected.
• The algae uses sunlight, water and carbon dioxide to make a hydrocarbon molecule, which is passed to the bacteria, which "eats" it, freeing carbon dioxide and hydrogen. The CO2 goes back to the algae to be used again, while the hydrogen is collected. As a bonus, the algae generates oxygen, which could make this system apt for space station fuel/air supplies.
  
• As a bonus, the algae generates oxygen, which could make this system apt for space station fuel/air supplies.

  • Maybe, but what about the anaerobes? How do scientists stop the generated oxygen from affecting the bacteria?
• this is the perfect time for designers and architects to begin thinking about how their introduction might alter the social and urban landscape.
• These systems are still in their infancy

  • This is an early 2005 article, so these systems were still in their infancy....5 years ago.
• what opportunities for integration into a city are there.

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• Eukaryotic green algae were discovered to produce hydrogen under anaerobic conditions already during the  1940's.
• the crucial enzyme in Chlamydomonas is a hydrogenase
• hydrogenase is believed to  be involved in photosynthesis.
• hydrogenase have a efficiency that is much higher than for nitrogenase it is also unfortunately  more sensitive towards oxygen, than the nitrogenase, which makes hydrogen production much more  difficult in Chlamydomonas.
• the mechanism behind hydrogen production is that the hydrogenase combines protons and  electrons from reduced ferredoxins to create hydrogen.
• the algae need to be in an anaerobic environment to be able to produce hydrogen.
• When no oxygen is  present ferredoxin "gives" the electrons to hydrogenase instead of oxygen and hydrogen is produced  (anaerobic Mehler reaction).
• the expression of the gene that encodes for hydrogenase is induced by anaerobic  conditions.

• It is at this moment not clear what  this energy source is exactly or how it is done but it seem to be an endogenous substrate with carbon  dioxide being one by-product.

  • So the Chlamydomonas produce carbon dioxide as well?! That's kind of...a bad thing, right?
• n dim light the photosynthesis releases less oxygen and the cells become anaerobe (remember  the compensation point) and the hydrogenase is able to operate.
• eriments have shown that the easiest way to produce hydrogen has been to decrease the light  intensity.

  • So not only do these algae need an anaerobic environment to manufacture the hydrogen...the light has gotta be reduced as well...(just so happens that several of those big circle vat things at the wastewater treatement plant were covered up. So if this were used in wastewater treatment....wait, can algae be used for wastewater treatment? can it take the filth and toxicity?)
• But only a small amount of hydrogen  can be produced, not enough for commercial production.

  • AAAahhh What?! Chlamydomonas reinhardtii algae CANNOT PRODUCE ENOUGH HYDROGEN (Even under optimum anaerobic conditions) FOR COMMERCIAL PURPOSES?! IS THAT WHAT YOU SAID?!
• Mutant prokaryotic organisms with a hydrogenase that can tolerate higher concentrations of  oxygen do for example already exist. The idea is therefore to do the same to Chlamydomonas and create  mutants that contain a more oxygen tolerating hydrogenase. If this were possible the  single-stage-process would be much more advanced compared to the two-stage-process, in terms of  yield, cost and effectiveness. The reason for that is the ability for Chlamydomonas to produce hydrogen  continuously.

  • If scientists could increase Chlamydomonas' tolerance of oxygen, the algae'd yield a whole lot more hydrogen. Since this is a September 2001 document, look it up. Have scientists been able to meaningfully increase the algae's oxygen tolerance by 2010?
• Since  photosynthesis decline much quicker then respiration an equilibrium point is reached after a while, usually  after 22 hours (fig 4). After that time the amount of oxygen that is used in respiration is greater then the  oxygen released by photosynthesis and the algae can be defined as anaerobic. It is at this point that  hydrogen is produced in larger amounts.

  • I suppose this is the "compensation point" mentioned a bit earlier in the document.
• When this is done in real life the algae are allowed to grow and feed in a normal way for some time to be  able to store energy. Thereafter they are moved to a new bottle with no sulphur present and when all  the oxygen is consumed (after 22 hours) hydrogen starts to bubble up from the top of the bottles into a  hydrogen collection tubes. The algae can produce hydrogen for up to four days before it needs to refill  its energy storage.  

  • After 22 hours, algae begin to produce hydrogen. The algae produce the stuff continuously for four days 'til they need an energy refill. (more biomass! yeah!)
• The future looks very bright right now for Chlamydomonas as a hydrogen producer. It is true that in the  two-stage-process of producing hydrogen there is a need to increase the yield by a factor of hundred or  more.

  • So the yield needs MAJOR improvement, but research is still going strong by 2008 and probably 2010! they're messing with the genes...transgenic Chlamydomonas ...check out this guy, who's mentioned in this last paragraph on this here page, who's been researching....most recent publications: http://epmb.berkeley.edu/facPage/dispFP.php?I=25#pubs

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