Surface Area enhancement of biochar and forestry biomass through activation by means of chemical impregnation with ZnCl2 and H3PO4

This dissertation is dedicated to the research of methods for the production of activated carbon by means of chemical impregnation from renewable resources such as waste biochar and forestry biomass. The goal of the research is to find a method that generates high performances activated carbon which can be scaled up and added to the supply chain of an already existing gasification concept located in Innsbruck, Austria. Biochar has been impregnated with ZnCl2 in ratios of 1:1 and 5:1 and activated in a mixed bed reactor in presence of H2O steam in a temperatures range of 500 and 700 °C for 30 and 60 minutes. Forestry biomass and biochar have been impregnated with ZnCl2 and H33PO4 in ratios of 1:1, 3:1, 5:1 then pyrolyzed at 500 °C for 1 hour. The activated carbon has been characterized through N2 adsorption at 77 K, total carbon content and scanning electron microscopy. The best results were obtained with the ZnCl2 5:1 impregnated biomass pyrolyzed at 500 °C for 1 hour, with a specific surface area of 1626 m2/g, a total pore volume of 0,79 cm3/g with a microporous percentage of the 75%, and a total carbon content of 84%.