Steam gasification of tire char supported by catalysts based on biomass ashes

Abstract

The aim of this work is to assess the feasibility of steam gasification of tire char and the impact of various biomass ashes (sunflower husk, beet pulp, beech chips and corn cobs) in the process. Samples of tire-char and char-catalysts (in the amounts of 5, 10 and 15 wt%) were subjected to gasification in isothermal conditions (800–1000 °C) at a pressure of 1 MPa, using the thermovolumetric method based on an analysis of the composition of the resulting gas. Changes in the formation rates of the main gas components (CO, H2, CO2 and CH4), maximum carbon conversion, half times conversion, yields and composition of gas components and H2/CO ratio were determined. Kinetic parameters (activation energy and pre-exponential factor) of the gasification reaction were calculated using the grain and random pore models. The correlations between the content of individual elements in ashes and parameters describing tire char gasification were assessed. The addition of a catalyst and increasing its loading improved the reactivity of the tire-char at up to 850 °C and had a significant but temperature-dependent impact on gas component yields. Performing catalytic tire char gasification under appropriate selected conditions (800–850 °C and 10/15 wt% of sunflower husk and beech chips ash as catalysts) may be an attractive way to efficiently obtain a hydrogen-rich gas.