Nitrogen-containing gaseous products of chrome-tanned leather shavings during pyrolysis and combustion

Abstract Chrome-tanned leather shavings (CTLS) are a type of solid waste generated from the leather industry. In this study, the pyrolysis and combustion of CTLS in nitrogen and air, respectively, were investigated using a thermogravimetric analyser coupled with Fourier transform infrared spectroscopy (TG-FTIR). A heating rate of 20 °C min −1 was applied, with a final temperature of 1000 °C. The pyrolysis process can be subdivided into three stages (drying the sample, fast thermal decomposition and a further cracking process), whereas the combustion process can be subdivided into four temperature stages. The TG/DTG curves for pyrolysis and combustion were similar at lower temperatures. Multiple peaks were observed for combustion in the temperature range of 250 °C to 580 °C. The emissions of CO 2 , NH 3 , HCN, HNCO, CO, acid and hydrocarbon were identified in CTLS pyrolysis. Similar gaseous products of combustion were found at lower temperatures, whereas CO 2 is the dominant product of combustion at higher temperatures. Combustion was found to be better for disposal of CTLS than pyrolysis.