ИСТИНА

Short-chain (C2–C5) volatile alkanes have a negative effect on the environment. They contribute to the formation of tropospheric ozone and toxic oxygenated volatile organic compounds (OVOC) such as acetone, formaldehyde and acetaldehyde [1]. The main anthropogenic sources of alkanes are petroleum industry and vehicle emissions. A catalytic oxidation with oxygen (conventional oxidation) is widely used to remove volatile alkanes; however, this process requires relatively high temperatures (≥ 350 °C). The main reason for the poor efficiency of conventional oxidation at low temperatures is an insufficient reactivity of alkanes. We propose a new highly efficient method for the removal of volatile alkanes. The idea is to promote the catalytic oxidation process at low temperatures by addition of ozone to an air flow containing the alkane impurities. Thus, it has been shown for the first time that volatile alkanes can be oxidized over a Mn/Al2O3 catalyst with high efficiency, even at 25–250 °C. Comparison of the catalytic data with the results of a complex physicochemical study of the catalyst (SEM-EDX, XRD, XPS, and H2-TPR) suggested that the remarkable efficiency of the alkane oxidation at low temperatures can be attributed to the presence of Mn2O3 species and oxygen vacancies on the catalyst surface, which are favorable for the ozone decomposition process. Because of the ozone decomposition, highly reactive oxygen species (atomic oxygen, peroxide, and OH radicals) are formed and completely oxidize alkanes, even at ambient temperatures.