1. Laboratory of Applied Physical Chemistry and Environmental Technology, Department of Chemical Engineering, K.U.Leuven, W. de Croylaan 46, B-3001 Leuven, Belgium, Laboratory of Chemical and Biochemical Process Technology and Control, Department of Chemical Engineering, K.U.Leuven, W. de Croylaan 46, B-3001 Leuven, Belgium, and Department of Energy Efficiency in Industry, Energy Research Centre of The Netherlands, ECN, Westerduinweg 3, 1755 ZG Petten, The Netherlands