A Combined TG–FTIR Study on the Pyrolysis of Waste Generated in the Coffee Production Chain

The results of a study on the pyrolysis of agricultural (coffee husks and parchment) and agroindustrial (two types of spent coffee grounds) waste from coffee production are presented. A study of the temperature dependence of the weight loss of samples during pyrolysis and the qualitative analysis of the main volatile substances were carried out using a thermogravimetric analyzer (TG) coupled with a Fourier transform infrared spectrometer (FTIR). The main stages of thermal decomposition of the samples were presented at four heating rates of 5, 10, 20, and 30 K/min. The results of an analysis of IR spectra for the volatile components of pyrolysis products of four materials were shown, and the temperature dependences of the absorption band intensities of the main gaseous pyrolysis compounds were plotted.