NAP PEPICO: extracted peak areas atm/z42 (9.65 eV). CH3Cl:CO:Ar=1:0(16):99(83),T=723 K,GHSV=24000 cm3h-1gcat-1, quartz tube reactor with 3 mm inner diameter and a small outlet hole size of 0.1 mm. Inset: comparison of the photoionization mass spectra at 9.65 eV obtained in LP and NAP PEPICO for both MCTH and CO-MCTH.