The present work aims to effect the thermal degradation of corn cob for the production of bioproducts (bio-oil and activated carbon), the latter being used in the preparation of filters for the dechlorination of water supply. The biomass under study and the products generated by pyrolysis in a fixed bed reactor were analyzed using classical methods (moisture, volatile materials, ash and fixed carbon, lignin, cellulose, hemicellulose and bulk density) and instrumentation (thermogravimetry, Fourier Transform Infrared Spectroscopy, Scanning Electron Microscopy and CHN). The bio-oil was analyzed by gas chromatography coupled to mass spectrometry (GC-MS). In the pyrolysis process, the following parameters were studied: temperature (360 to 640 ºC) and heating rate (13 to 27 ºC/min), the reaction time was 30 minutes. The dechlorination test using activated carbon obtained in this research was done in a continuous flow filtration column at an average flow rate of 6 mL/min. The results showed that the carbon content (44 %) and the lignin content (28 %) point to the use of the residual biomass studied in this research for the production of bio-oil and activated carbon via the thermal route. The highest yield for solid fraction (activated carbon) was 71.12 % at a temperature of 360 °C with a heating rate of 20 °C/min. While the minimum yield was 21.6 % with a temperature of 600 °C and a heating rate of 25 °C/min. Aliphatic hydrocarbons were found to be higher in the bio-oil in the present study (49 %) followed by 31 % oxygenated aromatic compounds. The bio-oil of the corncob obtained showed the following characteristics: pH 2.5 at a temperature of 25 ºC and apparent density of 1.52 g/cm³. The charcoal obtained in the research presented porous cavities on its surface, which indicates its use in adsorption systems of chemical species. Activated carbon was efficient in the process of dechlorination of the water supply. The efficiency in the removal of chlorine in the filtration system with the coal from this research was 100 % over the monitored period (26 uninterrupted days of operation).
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