Efeito da ativação por vapor ou dióxido de carbono na porosidade do carvão ativado produzido a partir de briquetes de bagaço de malte e levedura

Abstract

The present work aimed to evaluate the influence of activating agents (CO2 or water vapor) on the porosity of activated carbons produced by Nakamura (2014) and Da Silva (2016) from malt bagasse briquettes (BMS) and cream of malt. yeast (CL). In the pyrolysis step of the briquettes, the authors obtained average yields of 23.40%, 57.08%, 19.58% for biochar, pyrolytic liquids and gases, respectively. Biochar activation was performed at 850 °C using CO2 (Nakamura, 2014) or N2 + water vapor (Da Silva, 2016) at different activation times (2, 4 and 6 hours). Granulated activated carbons (GAC) were characterized by means of N2 physisorption isotherms and iodine number. For both activating agents, the increase in activation time provided the development of CAG porosity, indicated by the increase in the specific surface area, pore volume and iodine number. Activation with water vapor produced a greater development of meso and macroporosity than activation with CO2, resulting in a wider distribution of pore size. From the results obtained, it can be seen that both activating agents can be used in the production of CAG, generating adsorbents with different pore characteristics.