Destruction of toluene by rotating gliding arc discharge

• A rotating gliding arc (RGA) discharge reactor is developed for tar destruction.
• The highest destruction efficiency could exceed 95% using toluene as tar surrogate.
• The two major gaseous products are hydrogen and acetylene.
• The liquid and solid byproducts are collected and determined.

Non-thermal plasma is considered as an alternative treatment of tar present in the effluent from gasification processes. In this study, a novel rotating gliding arc (RGA) discharge reactor was developed for tar destruction. Toluene in nitrogen flow was used as a tar surrogate. The physical features of RGA discharge and its application to toluene destruction are investigated at different input concentrations and total gas flow rates. As a result, the highest destruction efficiency could exceed 95%, with a toluene concentration of 10 g/N m3 and a total flow rate of 0.24 N m3/h. The two major gaseous products are H2 and C2H2, with maximum selectivity of 39.35% and 27.0%, respectively. A higher input concentration slightly reduces this destruction efficiency but the energy efficiency further expanded, with a highest value of 16.61 g of toluene eliminated/kW h. In addition, the liquid and solid byproducts are collected downstream of the RGA reactor and determined qualitatively and semi-quantitatively. The amount and structure of these by-products is instructive for reaching a better comprehension of the chemical consequences of plasma treatment to the model compound and to the carrier gas nitrogen.