Date of Award
M.S. in Engineering Science
Gregg R. Davidson
Louis G. Zachos
Adsorption of co2 on mineral surfaces accounts for a small percentage of the terrestrial co2 sink. Volcanic ash is virtually free of co2 when erupted and has a high surface area resulting in a high capacity for co2 adsorption. Volcanism is commonly assumed to be only a source of co2, but pyroclastic eruptions can also potentially serve as a sink. Adsorption was investigated for 6 volcanic ash samples of andesitic composition from four volcanoes: Okmok, Redoubt, Spurr, and Tungurahua. The eruption of volcano redoubt released 0.75 x 109 metric tons of co2 and 55 x 109 kg of ash throughout the 3 week eruption. The eruption of mount Spurr released 85,000 co2 and 36 x 109 kg of ash throughout the duration of the eruption. The eruption of volcano Tungurahua released 29 x 109 kg of ash. Co2 emissions from the eruption of volcano Tungurahua were not measured. Co2 emissions and mass of tephra released from the eruption of mount Okmok were not measured. The calculations for adsorption percent for these two volcanos were performed using the ash/co2 ratio from mount Spurr and volcano Redoubt. The ratio was then applied to Okmok and Tungurahua to solve for co2 emissions for each of these ratios. The calculations for co2 adsorption for mount Okmok were performed using the mass of tephra from volcano Kasatochi (an adjacent, similar erupting volcano). Adsorption on each of the six ash samples ranged from 34.3 to 67.2 mg of co2 per kg of ash. Adsorption ranged from 0.04 to 0.45 mg co2 per m2 volcanic ash.
New, Lee, "CO2 Adsorption On Volcanic Ash: Net Contribution Of Volcanic Eruptions To The Global Carbon Cycle" (2017). Electronic Theses and Dissertations. 985.