Heptane dry reforming and coupling with partial oxidation in gliding arc discharge plasma for H2 production

Dry reforming (DR) of n-heptane and coupling of DR with partial oxidation reforming (POR) were investigated through experiments and simulations in a gliding arc discharge (GAD) plasma reactor. The effects of the input power, the molar ratio of oxygen to carbon, and the residence time on the DR process were evaluated according to the conversion rate, product selectivity and the energy yield of hydrogen. The highest CO2 conversion was 42.6%, which was higher than other CO2 splitting technologies in the gliding arc discharge plasma. The coupling of DR and POR achieved better results by adding air to the DR of n-heptane to form a thermal coupling process. Optical emission spectra of n-heptane DR and coupling DR with POR of n-heptane were investigated, respectively. Different reactive species including C2(A3Πg-X3Πu), CO2+(A2Πu-X2Πg), CO(a’3Σ+-a3Π), CO(d3Δ-a3Π) and O+(4P-4S0) were detected. A zero-dimension (0-D) model of heptane DR containing 163 reactions was established in Chemkin to describe the effect of O/C. The 0-D model of coupling DR with POR with 193 reactions was also established. [Display omitted] •Dry reforming(DR), coupling DR with partial oxidation reforming (POR) of n-heptane was investigated in GAD plasma.•H2 and CO selectivities, CO2 conversion in coupling DR & POR are more than those of DR.•Two 0-D models with Chemkin were established, and pathways were shown according to results of 0-D models.•Optical emission spectrum was utilized for detecting radicals to provide basis for models.