Evidence suggests that the recent drastic changes in the global climate have been caused by greenhouse gases, especially CO2. As a result, scientists are aiming to develop processes that either minimize the production of these gases or convert them into products of higher value. To that end, the catalytic properties of a two-dimensional boron-rich material were investigated. Herein is reported that such a material can reduce CO2 into benzene, C3 species, and C4 species at relatively low temperatures (225-450 ℃) and pressures (0.38 MPa). Current data suggest that a low-temperature induction period (e.g., 225 ℃) is needed to achieve the conversion of CO2 into benzene whereas the conversion of CO2 into light hydrocarbons does not require such a pretreatment. Additionally, it was found that Al1-xB2 loses its activity after approximately 17 hours. Such loss of activity may be due to the buildup of non-volatile compounds on the active sites (coking). Work presented here also indicates that Al(OH)3 species left behind after the preparation of Al1-xB2 act synergistically with the boron sheets, enhancing activity. The level of enhancement appears to depend heavily on the way Al(OH)3 is introduced into the system. Grinding amorphous boron and Al(OH)3 by hand afforded the greatest reactivity towards CO2, albeit it needs to be confirmed whether the B atoms are being actively consumed during the reaction. On the other hand, exposing Al1-xB2 to air during its synthesis yields a more reactive material, suggesting that air plays a significant role. Based on this, if the synthetic route of Al1-xB2 is optimized, it is certain to yield an industrially suitable catalyst. Finally, ∆Gºrxn calculations can be utilized to partially predict the observed product distributions, albeit more advanced calculations are needed.
Bachelor of Science (B.S.)
College of Sciences
Berger, Jose C., "Heterogenous Reduction of CO2 Over Boron-Rich AlB2" (2022). Honors Undergraduate Theses. 1293.