Increasing utilization of biogas as an energy source sets various design requirements for gas quality and gas cleaning systems. This study presents efficiency tests for three different siloxane removal systems: activated carbon, silica gel and molecular sieve based systems. Tests were performed in a nitrogen matrix. The injected impurities were siloxane compounds (D5, D6), limonene and toluene. The activated carbon and molecular sieve systems had the highest siloxane removal efficiencies in these tests. Silica gel media also had a good siloxane removal efficiency, and it was more selective in the removal of siloxanes than the other systems. (C) 2015 Elsevier B.V. All rights reserved.