Icon for: Chris Hill

CHRIS HILL

University of California at Berkeley
Years in Grad School: 1

Judges’ Queries and Presenter’s Replies

  • Icon for: Marc Porter

    Marc Porter

    Judge
    May 20, 2013 | 10:47 a.m.

    Two questions….

    Are their estimates on the value add for the product from the reaction of furan and butanol?

    What type of tox studies are being pursued?

  • Icon for: Chris Hill

    Chris Hill

    Presenter
    May 21, 2013 | 11:46 p.m.

    Good question; definitely has implications for the viability of this technology. As a low estimate, the product should have at least a 20% value added over butanol, due to its higher energy density. Additional value should come from it’s lower corrosivity/hygroscopicity, from removal of the hydroxyl group on butanol.

    The full picture is more complex though, since methylfuran appears too toxic to use as a fuel directly, and is potentially abundant. Thus methylfuran may be of little value (at large scale) unless it’s used as a substrate for synthetic fuel. In this case the value added could be 100 to 1000% as an estimate relative to a methylfuran plus butanol.

    Computational and cell-based studies are being pursued. The computational approach is to relate select molecules to known toxicity hazard traits, and than to search nearby chemical space to see if less toxic structural analogs exist. Cell based studies are focused on ecological toxicity and mammalian toxicity, where representative cell types are chosen and well-characterized toxicity endpoints are selected as a basis to compare candidate chemicals.

  • Icon for: Jon Kellar

    Jon Kellar

    Judge
    May 20, 2013 | 11:39 a.m.

    What is meant by “local models” and how are these different than non-local models?

  • Icon for: Chris Hill

    Chris Hill

    Presenter
    May 22, 2013 | 12:00 a.m.

    By local models, we mean understanding a set of structurally related chemicals with reference to their toxicological behavior. Since I am studying the products of butanol-methylfuran coupling reactions, the products will share many characteristics, so many analogies between these compounds can be drawn when comparing these chemicals.

    Non-local models would compare chemicals from a much greater portion of chemical space, or according to criteria that are applicable over a larger portion of chemical space. This type of model makes more sense if structurally unrelated molecules are being compared.
    The ability to predict toxic effects of chemicals using local models (with the help of mechanistic toxicity experiments on some of the compounds), is feasible today. The use of non-local models in predictive toxicology is much more difficult. Local models should be sufficient for my purposes for now, but if I expand my set of substrates, the challenge of relating the toxicity of structurally very different compounds will become more relevant.

  • May 20, 2013 | 04:16 p.m.

    Fish cells (used in tox studies) and not human. How do you correlated the fish cell toxicity with a human toxicity?

  • Icon for: Chris Hill

    Chris Hill

    Presenter
    May 21, 2013 | 11:53 p.m.

    The fish cell studies are a model for ecological toxicity. For mammalian toxicity investigations, mammalian cell-based studies using candidate fuel compounds and structural analogs will elucidate toxicity endpoints. To learn about toxicity mechanisms to allow prediction of new compounds toxicity (and better feedback between chemistry and toxicology), computational models of these compounds will also be used that can be correlated with well-characterized structural motifs and toxic metabolic pathways.

  • May 20, 2013 | 04:38 p.m.

    What are the economic considerations of the approach (e.g., the Ru catalyzed reaction of methylfuran and 1-butanol to obtain a “high quality synthetic biofuel”)?

  • Icon for: Chris Hill

    Chris Hill

    Presenter
    May 21, 2013 | 11:47 p.m.

    The main economic considerations are energy requirements for the process, cost of the Ru catalyst, and relative value of the methylfuran and butanol versus product. The process in it’s current stage uses a temperature of 110oC, which is mild by biofuel generation/processing standards, and relatively low energy. This type of low temperature conversion is a key benefit of homogeneous catalysis.

    Regarding catalyst cost- ruthenium is an expensive metal, which is a definite drawback for scale-up. Nevertheless, the catalyst could potentially be recovered and reused. The use of precious metals for industrial scale processes can be reasonable; a classic example is the use of rhodium and iridium catalysts for hydroformylation reactions (acetic acid synthesis).

    Regarding value increase for product, it is relevant that we are considering making a fuel from these two compounds. The fuel market is large, with prices set by petroleum. Methylfuran is potentially competitive with gasoline (high yield production possible from biomass), but likely not useable due to toxicity. Butanol is a pretty good fuel, but lags behind economically, as bioconversion methods for its production have low yield (about 30% for ABE process) and low productivity. By using methylfuran along with the butanol, a cheaper than butanol product that’s fit for the market (energy dense, acceptable toxicity) may be acheived.

  • Icon for: Chris Hill

    Chris Hill

    Presenter
    May 22, 2013 | 12:04 a.m.

    I would be happy to respond to follow up questions!

  • Further posting is closed as the competition has ended.

Presentation Discussion
  • May 21, 2013 | 11:28 a.m.

    Hi Chris, this is very important research! and thanks for making the video easy-to-understand for non-technical audience. Good luck!

  • Icon for: Chris Hill

    Chris Hill

    Presenter
    May 23, 2013 | 02:45 a.m.

    Hey Federica, thanks so much! Best of luck to you to!

  • Icon for: Leah Rubin

    Leah Rubin

    Trainee
    May 23, 2013 | 02:57 p.m.

    Nicely done video, Chris!

  • Further posting is closed as the competition has ended.