Dielectric Barrier Discharge Initiated Gas-Phase Decomposition of CO2 to CO and C6–C9 Alkanes to C1–C3 Hydrocarbons on Glass, Molecular Sieve 10X and TiO2/ZnO Surfaces

摘要

Atmospheric Pressure Dielectric Barrier Discharge (APDBD) initiated decomposition of CO2 and C6–C9 alkanes (in Ar carrier) with uncoated and TiO2/ZnO coated glass surfaces, and under molecular sieve 10 X packing are presented in this study. Alkanes employed include 2-methylpentane, cyclohexane, n-hexane, n-heptane, n-octane, n-nonane and their decomposition products studied include C1–C3 hydrocarbons viz. CH4, C2H4, C2H6 and C3H8. Generally the yields of all these C1–C3 products increased with discharge energy, however to a major extent the parent alkane structure controlled the relative concentration profiles of the individual products. Typically the slopes of the increase in various products yield varied from 0.025 to 0.25 ppm (v/v) mm V?1. However, in the case of cyclohexane the total yield of methane, ethane and propane were only ～20% of ethylene yield. Use of TiO2 as well as TiO2/ZnO coated central glass electrode in the APDBD apparatus showed ～11% enhancement in $ hbox{CO}_{2} rightarrow hbox{CO} $ degradation efficiency. However, while overall 2-methylpentane decomposition reduced significantly to ～30%, in case of n-octane its decomposition to the C1–C3 products remained unaffected. On the other hand under molecular sieve 10X packing, yield of CH4 and C2H4 increased significantly in both cases.