Porous materials are interesting candidates for gas storage in different applications. The present study analyses at room temperature the high pressure storage of H 2 , CH 4 and CO 2 in a number of porous carbons (eight monoliths and two powdered activated carbons). The samples cover a wide range of porosities and densities (monoliths having high porosity with moderate density or moderate porosity with high density) with the aim to discuss the relative importance that the sample surface area has on the volumetric storage capacity, in relation to the importance of the density of the material. Our results show that the gravimetric storage capacities of the three studied gases are controlled by the textural properties of the adsorbent, whereas the volumetric storage capacities are mainly controlled by the adsorbent density. High volumetric excess adsorption capacity values (for example, H 2 : 10 g l À1 ; CH 4 : 110 g l À1 and CO 2 : 440 g l À1 ) correspond to monoliths having high densities, despite their moderately developed porosities. This paper also compares these results with those obtained similarly (same gases and same experimental conditions) using the highest known surface area material (MOF-210). In summary, our volumetric results, obtained with commercially available ATMI monoliths and their CO 2 activation, are, to the best of our knowledge, amongst the highest that have been reported; higher than the high surface area samples of the M3M monolith prepared from Maxsorb (S BET : 2610 m 2 g À1 ) or MOF-210 (S BET : 6240 m 2 g À1 ). Although a variety of MOFs have been reported to exceed our results, oftentimes these values are overestimated due to the fact that the volumetric capacity of MOFs was calculated using crystal density rather than experimentally measured density.
The deposition of organic material, or coke, on hydroprocessing catalyst was studied using Athabasca bitumen vacuum residue (ABVB) and narrow fractions of ABVB, prepared by supercritical fluid extraction (SCFE) with n-pentane. The feed materials were diluted in a lowsulfur gas oil and hydroprocessed over a commercial NiMo/γ-Al 2 O 3 catalyst in a 1 L continuousstirred tank reactor at 440 °C. The coked catalysts were Soxhlet extracted with methylene chloride; then, carbon content, surface area, pore volume, and pore size were measured. Hydrodesulfurization activity was then measured using bitumen and dibenzothiophene as reactants.The SCFE fractions that contained only saturates, aromatics, and resins gave a low yield of carbon on the catalyst (<7.5 wt %). The asphaltene-rich fraction gave higher coke yields, both on the catalyst and in the reactor, and a lower H/C ratio than the lighter fractions. In the worst case with asphaltene-rich feed, over half of the surface area and pore volume of catalyst was lost due to coke deposition on the catalyst. HDS activity of the spent catalyst decreased monotonically with increasing carbon content on the catalyst. A portion of the carbonaceous material, or coke, on the catalyst was mobile and reactive at the conditions used for hydroprocessing of bitumen. The data suggested that this mobile adsorbed material had a significant impact on the observed activity of the catalyst.
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