The study of toluene conversion, in a gas such as the one obtained during the pyrolysis of biomass, was conducted at atmospheric pressure in homogeneous and in coupled plasma-catalytic systems. The effects of discharge power, initial concentration of toluene, and the presence of the bed of NiO/Al2O3 - G-0117 (industrial catalyst for methane water shift) on the conversion of C7H8, the composition of the outlet gas, and its calorific value have been investigated. The gas flow rate was 1000 Nl/h and the initial gas composition was CO (0.13), CO2 (0.12), H2 (0.25), and N2 (0.5). The initial toluene concentration was in the range of 2000–4000 ppm. The obtained results show that the conversion of toluene increases with discharge power and the highest one was obtained in the coupled plasma-catalytic system. It was higher than that in the homogeneous system of gliding discharge plasma. The composition of gas changed within the range of a few percent. In the outlet gas acetylene, ethylene and ethane were observed. Trace amounts of toluene were reduced to benzene and formed C3 and C4 hydrocarbons. In an extended process, the reduction of NiO to metallic nickel, methanation reaction of carbon oxides, and an increase of the conversion of toluene were observed. The conversion of toluene in the extended process was 92%. The catalytic activity of G-0117 in a coupled system increased during the study conducted for about 40 min. The use of G-0117 catalyst led to an increase in the calorific value of the outlet gas. In every examined system, it was above the minimal level demanded by engines and turbines. After the process, carbon deposits were present.

Gliding discharge and coupled plasma-catalytic system were used for toluene conversion in a gas composition such as the one obtained during pyrolysis of biomass. The chosen catalyst was G-0117, which is an industrial catalyst for methane conversion manufactured by INS Pulawy (Poland). The effects of discharge power, initial concentration of toluene, gas fl ow rate and the presence of the bed of the G-0117 catalyst on the conversion of C 7 H 8 , a model tars compounds were investigated. Conversion of coluene increases with discharge power and the highest one was noted in the coupled plasma-catalytic system. It was higher than that in the homogeneous system of gliding discharge. When applying a reactor with reduced G-0117 and CO (0.15 mol%), CO 2 (0.15 mol%), H 2 (0.30 mol%), N 2 (0.40 mol%), 4000 ppm of toluene and gas fl ow rate of 1.5 Nm 3 /h, the conversion of toluene was higher than 99%. In the coupled plasma-catalytic system with G-0117 methanation of carbon oxides was observed.

A coupled plasma-catalytic system (CPCS) for the conversion of toluene was investigated and compared to the homogeneous system of gliding discharge plasma. Toluene was used as a model compound, which is present in tars. The study was carried out at atmospheric pressure, in a gas composition similar to the one obtained during pyrolysis of biomass. The effect of the initial toluene concentration, energy supplied to gliding discharge (GD) and the presence of a catalyst on the conversion of toluene was studied. Both the composition of outlet gas and its calorific value were monitored. Based on the obtained results it can be concluded that the conversion of toluene increases with the increase of gliding discharge power. The highest toluene conversion (89%) was received in the coupled plasma-catalytic system (catalyst: RANG-19PR) under the following conditions: CO (0.13 mol. fr.), CO2 (0.12 mol. fr.), H2 (0.25 mol. fr.), N2 (0.50 mol. fr.) and 4400 ppm of toluene with a gas flow rate of 1000 Nl/h. The composition of the outlet gas in the homogeneous system and in the CPCS changed in the range of a few percents. Toluene levels were reduced tenfold. Benzene, C3 and C4 hydrocarbons, as well as acetylene, ethylene and ethane, were detected in the outlet stream in trace amounts. Carbon deposits were present in the reactor. The products of methanation of carbon oxides were detected in the both studied systems. A mechanism of toluene decomposition in the CPCS was proposed. The application of the catalyst brought about an increase in the calorific value of the outlet gas. It was above the minimal level demanded by engines and turbines.