This article describes measurements of methane purification by condensed rotational separation. First, the separation concept is introduced. Then the test-setup and measurements are described. The thermodynamic performance of the system is compared with thermodynamic predictions and is found to be in good agreement. The separation performance of the centrifugal separator is addressed. (C) 2009 American Institute of Chemical Engineers AIChE J, 56: 150-159, 2010