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Recently, salt-assisted pyrolyzation has been deemed an emerging and efficient method for the preparation of biochars due to its facile operation as well as its good structural and chemical properties. In this work, biochars (MBCx) are prepared by heating bamboo powders in eutectic salts (Li2CO3 + K2CO3) at 500–600 °C in the air. Multiple technologies are employed to examine the physiochemical properties of bamboo biochars. Correlations between heating temperature and structural features and carbon dioxide uptakes of bamboo biochars have been investigated. The results show that heating temperature has a significant influence on the physicochemical properties of bamboo biochars. With the elevation of the heating temperature, the defect structures of bamboo biochars gradually ascend, especially when the heating temperature reaches 600 °C. MBCx biochars visibly exceed conventional bamboo biochar prepared via pyrolyzation in a nitrogen stream free of salt addition. Pyrolysis of bamboo in eutectic salts endows biochars with higher oxygen content and more carbon defects, which likely accounts for their better CO2 capture activities. [ABSTRACT FROM AUTHOR]

Steam-CO2 reforming of biomass derived synthesis gas (bio-syngas) was investigated with regard to the steam concentration in the feed using Rh-loaded alumina foam monolith catalysts, which was also accompanied by thermodynamic equilibrium calculation. With 40 vol % steam addition, steam methane reforming and water gas shift reaction were prevailed at the temperature below 640 °C, above which methane dry reforming and reverse-water gas shift reaction were intensified. Substantial change of activation energy based on the methane conversion was observed at 640 °C, where the reaction seemed to be shifted from the kinetic controlled region to the mass transfer controlled region. At the reduced steam of 20 vol %, the increase in the gas velocity led to the increase in the contribution of steam reforming. Comparing to the absence of steam, the addition of steam (40 vol %) resulted in the increase in the production of H2 and CO2, which in turn increased the H2/CO ratio by 95% and decreased the CO/CO2 ratio by 60%. Rh-loaded alumina monolith was revealed to have a good stability in upgrading of the raw bio-syngas. [ABSTRACT FROM AUTHOR]