The influence of pH, temperature and hydrolyzate concentration on the removal of volatile and nonvolatile compounds from sugarcane bagasse hemicellulosic hydrolyzate treated with activated charcoal before or after vacuum evaporation

This paper analyzes the influence of pH, temperature and degree of hydrolyz ate concentration on the removal of volatile and nonvolatile compounds from sugarcane bagasse hemicellulosic hydrolyzate treated with activated charco al before or after the vacuum evaporation process. Furfural and 5-Hydroxyme thylfurfural were almost totally removed in all the experiments, irrespecti ve of pH and temperature and whether the charcoal was added before or after the vacuum evaporation process. Adding activated charcoal before the vacuu m evaporation process favored the removal of phenolic compounds for all val ues of pH. Acetic acid, on the contrary, was most effectively removed when the activated charcoal was added after the vacuum evaporation process at an acid pH (0.92) and at the highest degree of hydrolyzate concentration (f=4 ). However, addition of activated charcoal before or after vacuum evaporati on at an acid pH (0.92) and at the highest degree of hydrolyzate concentrat ion (f=4) favored the removal of both acetic acid and phenolic compounds.