Experimental hydrate dissociation pressures for (methane, carbon dioxide, or nitrogen + tetrahydropyran or furan + water) are reported in the temperature ranges of (278.8 to 299.7) K. An isochoric step-heating method was used to generate the experimental data. A comparison between the generated hydrate dissociation data for (methane + water) system in this work and corresponding data from the literature is set forth to confirm the reliability of the experimental method used herein. In order to investigate the promotion effects of tetrahydropyran and furan, the experimental results obtained for the systems containing these two chemicals are compared to some selected experimental data in their absence, reported in the literature. It is shown that both tetrahydropyran and furan have remarkable promotion effects and furan exhibits a slightly better performance. Moreover, the reliability of the literature data for the systems containing tetrahydropyran and furan is investigated. Finally, it is shown that the presence of THP or furan in the system has a negative effect on the kinetics of methane and carbon dioxide hydrate formation, and reduces the amount of gas uptake in the hydrate formation process. (C) 2015 Published by Elsevier Ltd.