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The synthesis of a sponge-like carbon aerogel from microfibril cellulose, with high porosity (99 %), ultra-low density (0.01 g/cm), hydrophobic properties (149° static contact angle) and reusability is reported in this paper. The physical properties, internal morphology, thermal properties, and chemical properties of carbon aerogels heat-treated at 700 and 900 °C (Samples C-700 and C-900) were examined. Stabilization and carbonization parameters were optimized in terms of residual carbon yield. The BET surface area of Sample C-700 (521 m/g) was significantly higher than of Sample C-950 (145 m/g). Graphitic-like domains were observed in C-950. The highest normalized sorption capacity (86 g/g) for paraffin oil was observed in sample C-700. The removal of hydrophilic function groups during carbonization causes carbon aerogel to present highly hydrophobic properties. Carbon aerogel's ability to absorb oil is enhanced by its highly porous 3D network structure with interconnected cellulose nanofibrils. [ABSTRACT FROM AUTHOR]

Quasielastic neutron scattering of H2 and D2 in the same nanoporous carbon at 10-40 K demonstrates extreme quantum sieving, with D2 diffusing up to 76 times faster. D2 also shows liquidlike diffusion while H2 exhibits Chudley-Elliott jump diffusion, evidence of their different relationships with the local lattice of adsorption sites due to quantum effects on intermolecular interactions. The onset of diffusion occurs at 22-25 K for H2and 10-13 K for D2. At these temperatures, H2 and D2 have identical thermal de Broglie wavelengths that correlate with the dominant pore size. [ABSTRACT FROM AUTHOR]

Abstract: Owing to several disadvantages of traditional hard template based synthesis, soft-template or self-assembly was adopted to synthesize mesoporous carbon. In this work, we have introduced hexaphenol as a new and large organic precursor for the synthesis of mesoporous carbon by self-assembly with Pluronic P123 as structure dictating agent. The resultant mesoporous carbon is bimodal in nature with median pore widths of 29 and 45Å and BET surface area of 312m2/g. Unlike previously synthesized mesoporous carbon, this carbon possesses negligible micropore volume. This mesoporous carbon is very suitable candidate for several applications including membrane separation, chemical sensor or selective sorption of larger molecules. [Copyright &y& Elsevier]

Abstract: The effect of mixing chemically-activated ultramicroporous carbon (UMC) with Pd nanopowder is investigated. Results show that Pd addition doubles the rate of hydrogen uptake, but does not enhance the hydrogen capacity or improve desorption kinetics. The effect of Pd on the rate of hydrogen adsorption supports the existence of the hydrogen spillover mechanism in the Pd – UMC system. [Copyright &y& Elsevier]

Abstract: Fabrication of uranium oxicarbide microspheres, a component of TRISO fuel particles for high temperature nuclear power systems, is based on the internal gelation of uranium salts in the presence of carbon black. In order to obtain a high quality product, carbon black should remain dispersed during all phases of the gelation process. In this study, the surface and structural properties of several commercial carbon black materials, and the use of dispersing agents was examined with the goal of finding optimal conditions for stabilizing submicron-sized carbon black dispersions. Traditional methods for stabilizing dispersions, based on the use of dispersing agents, failed to stabilize carbon dispersions against large pH variations, typical for the internal gelation process. An alternate dispersing method was proposed, based on using surface-modified carbons functionalized with strongly ionized surface groups (sodium sulfonate). With a proper choice of surface modifiers, these advanced carbons disperse easily to particles in the range of 0.15–0.20μm and the dispersions remain stable during the conditions of internal gelation. [Copyright &y& Elsevier]