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The biological production of H 2 by dark fermentation is being extensively investigated due to the great potential of the two-phase hydrogen/methane fermentation process for recovering energy from carbohydrate-rich wastes. However, the purification of the bio-hydrogen and biogas obtained is needed to produce high-purity H 2 and CH 4 streams appropriate for industrial application. In this study, the performance of three activated carbons (No1KCla-600, No1KClb-1000 and No2OS-1000), synthesized from phenol-formaldehyde resins, as potential adsorbents for CO 2 capture from bio-hydrogen and biogas streams has been evaluated under dynamic conditions. Adsorptiondesorption cycles by means of temperature swings were conducted at ambient temperature and atmospheric pressure with CO 2 /H 2 (40/60 and 70/30 vol.% at normal conditions) and CO 2 /CH 4 (50/50 vol.% at normal conditions) binary gas mixtures in a purpose-built fixed-bed set-up. The performance of the resin-derived carbons to separate CO 2 was superior to that of reference commercial carbons in terms of CO 2 uptake, breakthrough time and column efficiency. These adsorbents presented high * Corresponding author.

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Phenol-formaldehyde resins and a low-cost biomass residue, olive stones (OS), were used to prepare five activated carbons for CO 2 separation at atmospheric pressure, i.e., in post-combustion processes or from biogas and bio-hydrogen streams. Two phenolformaldehyde resins were synthesized: Resol, obtained by using alkaline environment, and Novolac, synthesized in the presence of an acid catalyst. Carbon precursors were prepared by mixing both resins with KCl or by mixing the Novolac resin with OS. The precursors were carbonized under an inert atmosphere of N 2 at different temperatures.The last stage in the synthesis of the adsorbents involved physical activation with carbon dioxide, which was carried out at different temperatures and burn-off degrees.Response surface methodology (RSM) is proposed as a tool for rapidly optimizing the activation parameters in order to obtain the highest possible CO 2 capture capacity of activated carbons. The optimum values of activation temperature and burn-off degree that maximize CO 2 uptake by the activated carbons at 35 ºC and atmospheric pressure were obtained within the experimental region. A value of CO 2 adsorption capacity of 9.3 wt.% was achieved. Activated carbons derived from Novolac phenol-formaldehyde * Corresponding author. Tel.: +34 985 119 090; Fax: +34 985 297 662 E-mail address: cpevida@incar.csic.es (C. Pevida) 2 resin type and from OS showed great potential as adsorbents for CO 2 capture at atmospheric pressure.

Enantiomerically pure syn-2-amino alcohols 6 are prepared by addition of diethylzinc to chiral alpha-(dibenzylamino) aldehydes 4. The addition is highly stereoselective, leading to syn-2-(dibenzylamino) alcohols 5 with excellent diastereomeric excesses (76-98%). Debenzylation of 5 by hydrogenolysis on Pearlman's catalyst yields quantitatively the amino alcohols 6.