PYROLYSIS OF CHROMED LEATHER WASTE SHAVINGS IN FLUIDIZED BED

The leather industry generates a large amount of solid waste, which sometimes has pollution potential. Chromium is often present in this waste: Thermal treatment proves to be a promising method for the reuse of leather waste. The pyrolysis process involves heating the biomass in an inert atmosphere. The products are gas, oil and carbonaceous solid residue (char). The present study main objective is to investigate the production of useful materials from chromed leather waste shavings (CLWS) pyrolysis. This waste was characterized by chromium, total Kjeldahl nitrogen and ashes content. Volatile content, higher calorific value, thermo gravimetric analysis (TGA) and scanning electron microscopy (SEM) were also determined A fluidized bed reactor was used for the tests. The parameter varied in the experiments was the temperature (723 K and 873 K), and heating rates (0,25 and 0,4 K/s). The product fractions yield was evaluated, and was found that the pyrolysis temperature of 873 K has a higher yield of oil. The oil was characterized using the technique of Fourier transform infrared spectrophotometry (FTIR) and gas chromatography with mass spectrometry, that showed the presence of oxygenated organic compounds (alcohols, phenols, ketones) and even non-oxygenated organic compounds (alkanes, alkenes, aromatics) in its composition. The char was characterized according to the techniques of SEM and energy dispersive spectroscopy (EDS). According to the results of these analyses, the char has a porous morphology and is basically composed of C, Cr, Na, Mg and Cl. Thus, the pyrolysis of CLWS appears as a promising alternative for the treatment of these residues, and to obtain useful products.