The methyl halide to hydrocarbons (MeXTH) reaction represents the second step in a potential two-step route from methane to light olefins or gasoline-range hydrocarbon mixtures. In this contribution, the methyl chloride to olefins reaction (MeXTO) was studied over a H-SAPO-34 catalyst with (Al + P)/Si = 19 by means of catalytic testing at 350-400 degrees C and WHSV = 11.7 h(-1), infrared spectroscopy and isotopic labelling experiments. Only minor degradation of the H-SAPO-34 material was observed by X-Ray diffraction or infrared spectroscopy after 5 sequential test-regeneration cycles at 400 degrees C and 550 degrees C, respectively. Co-feed experiments using (13)C-methyl chloride and (12)C-ethene or (12)C-propene at 400 degrees C indicated that the conversion level of each compound is directly related to its proton affinity. Furthermore, under the conditions used, no inhibitive effect of the alkenes on methyl chloride conversion was observed. Transient isotopic labelling experiments suggested that hexamethyl benzene is an important reaction intermediate in alkene formation from methyl chloride. However, the isotopic labelling of effluent products during (13)C-methyl chloride-(12)C-alkene co-feed experiments suggested that alkene methylation and interconversion reactions may contribute significantly to C(3)(+) formation. The findings are in general agreement with similar studies of the methanol to olefins reaction over the same catalyst topology. (C) 2011 Elsevier B.V. All rights reserved.