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Compared with fluorinated cycloalkanes and liner olefins, the degradation of chlorofluorocycloolefins is much easier with good environmental friendliness. However, the fire‐extinguishing performance of chlorofluorocycloolefins has been rarely explored. In this study, the fire‐extinguishing performance and working mechanism of octafluorocyclopentene (C5F8) and 1‐chloro‐2,3,3,4,4,5,5‐heptafluorocyclopentene (C5F7Cl) were studied by combined experimental and theoretical approach. It was found that, compared to C5F8, the asymmetry of C5F7Cl agent with the chlorine atom possesses a reduced energy barrier in pyrolysis process and its reaction with OH· radicals. Moreover, chlorine‐containing unsaturated active groups and CF2· radicals generated in C5F7Cl pyrolysis can effectively capture flame radicals. As a result, a relatively low minimum extinguishing concentrations (MECs) for suppressing methane‐air (5.37 vol%) and propane‐air flame (5.93 vol%) is achieved outperforms that of C5F8 (6.73 and 7.74 vol%), even better than reported fluorinated cycloalkanes and chlorofluoroolefins agents. This study shows that chlorofluorocycloolefins are promising Halon substitutes over perfluorocyclic olefins in fire‐extinguishing performance. [ABSTRACT FROM AUTHOR]

The sorption isotherms of xylenes in CoAlPO4-5 were measured by the gravimetric technique at 342K. The isotherms of para- and meta-xylenes followed typical type-I and could be well fitted by the Langmuir model; while the isotherm of ortho-xylene did not show a distinct saturation with the increase of pressure and could be then described by the Freundlich equation. In opposition to the adsorption in AlPO4-5, the isotherms of para- and meta-xylene in CoAlPO4-5 lay above that of ortho-xylene. The free energy change (ΔG) of adsorption increased with the loadings, while the diffusivities of xylenes decreased with the loadings. Moreover, the diffusivities of ortho-xylene were slower than those of other two isomers. [Copyright &y& Elsevier]

The sorption of benzene, cyclohexane and hexane in AlPO4-5 at a temperature of 303–675 K was simulated by the grand canonical Monte Carlo methods. The Burchart–Dreiding force field was proved to be suitable for the simulation. The Henry constants, isotherms, packing patterns and the average potential energy were obtained and compared with the experimental data from the literature. Moreover, Langmuir and Freundlich equations were used to correlate the isotherms and the surface curvature model was used to calculate the initial heat of sorption for benzene in AlPO4-5 and compared with other methods. [Copyright &y& Elsevier]