Heterogeneous catalysis is an exciting field in constant development. New and improved catalysts that can both be effective and economical are always on demand. Activated carbons may well play an important role in this field, as they are a cheaper alternative while more environmentally benign. In this paper, a brief overview of the effort developed in the application of activated carbon as heterogeneous catalysts in various reactions is presented. Functionalised activated carbon has been used as catalyst for fine chemical reactions. Gas-phase reactions for NO, N2O and CO2 conversions were thoroughly studied using activated carbon as catalyst support. In situ characterization techniques proved to be valuable tools to understand carbon gasification mechanism. (C) 2017 Elsevier B.V. All rights reserved.