| | Category | CH | P04 | Grow Your Own Gas: Making Cellulosic Ethanol From Common |
| | Biomass |
| | Abstract | The purpose of this experiment, “Grow Your Own Gas,” was to |
| | demonstrate that ethanol could be produced through the breakdown and |
| | fermentation of cellulosic biomass or any material containing rigid plant |
| | matter. The project consisted of three major steps: hydrolysis or |
| | breakdown of the cellulose in the biomass; fermentation of glucose; and |
| | separation. Five cellulosic materials were selected: grass, sawdust, |
| | banana peels, leaves, and newspaper. Then, three sets of these five |
| | materials were prepared for the experiment; groups were labeled A, B, |
| | and C to correspond to the method of hydrolysis used to break the material |
| | down. Group A was exposed to acid, B to cellulase (a cellulose- |
| | consuming enzyme), and C to both acid and enzyme, all for seven days. |
| | After hydrolysis, the decomposing biomasses were neutralized in pH with |
| | lye and fermented with yeast for six days. The resulting product, a mixture |
| | of a solid mash, liquid ethanol, and impurities, was separated; the mixture |
| | was strained through a wire mesh screen to remove the solids, and a |
| | freeze distillation process was used to remove water. |
| | Finally, after two rounds of separation, the resulting liquid was tested with |
| | coolant and alcohol breath strips which confirmed the presence of |
| | ethanol in all 15 samples. Group C, broken down by the combination of |
| | enzyme and acid hydrolysis, produced the strongest presence of ethanol. |
| | Overall, “Growing Your Own Gas” proved that renewable fuels, like |
| | bioethanol, can be produced from commonly-found cellulosic materials |
| | through hydrolysis, fermentation, and separation. |
| | Bibliography | "ABC's of Biofuels." U.S. Department of Energy - Energy Efficiency and |
| | Renewable Energy. 24 January 2008. U.S. Department of Energy. 24 April |
| | 2008 |
| | <<http://www1.eere.energy.gov/biomas/printable_versions/abcs_biofuels. |
| | html>>."Biomass FAQs." U.S. Department of Energy Energy Efficiency and |
| | Renewable Energy - Biomass Program. 24 January 2008. U.S. Department |
| | of Energy. 24 April 2008 |
| | <http://www1.eere.energy.gov/biomas/printable_versions/biomass_basic |
| | s_faqs.html >. |