Zeozymes: Sn‐Beta zeolite is found to be a highly active catalyst for the conversion of triose sugars. If the solvent is water, isomerization of the triose sugars takes place to form lactic acid in 90 % yield at 125 °C. If methanol is used as the solvent, an overall isomerization–esterification reaction takes place and methyl lactate is formed in quantitative yields at 80 °C. This represents one of the most selective zeolite‐catalyzed biomass transformation reactions.

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The cobalt carbide (Co 2 C) species was formed in some activated carbon supported cobalt-based (Co/AC) catalysts during the activation of catalysts. It was found that the activity of Fischer-Tropsch reaction over Co-based catalysts decreased due to the formation of cobalt carbide species. Some promoters and pretreatment of activated carbon with steam could restrain the formation of cobalt carbide.

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Nitrogen-incorporated SAPO-11 molecular sieves were synthesized by a secondary synthesis technique at low nitridation temperature (400 °C) with a starting material of SAPO-11 zeolite doped with 2 wt % Ru. The obtained powder samples showed high activity in Knoevenagel condensation, which acts as a probing reaction for base catalysis. The changes in structure of the nitrogen-incorporated samples were investigated by means of 27 Al-MAS NMR and 31 P-MAS NMR spectra, X-ray diffraction, and BET surface area measurements. It was found that nitrogen-containing species had incorporated into the framework of SAPO-11 zeolite, in which some N atoms directly bonded to Al and P atoms and formed AlN 4 , AlN 2 O 2 , and PN 4 groups. These species with terminal -NH 2 groups on the surface together were responsible for the basicity of nitrogen-incorporated SAPO-11 zeolite.

The effect of vanadium promotion on activated carbon (AC)-supported cobalt catalysts in Fischer-Tropsch synthesis has been studied by means of XRD, TPR, CO-TPD, H 2 -TPSR of chemisorbed CO and F-T reaction. It was found that the CO conversion could be significantly increased from 38.9 to 87.4% when 4 wt.% V was added into Co/AC catalyst. Small amount of vanadium promoter could improve the selectivity toward C 10 -C 20 fraction and suppress the formation of light hydrocarbon. The results of CO-TPD and H 2 -TPSR of adsorbed CO showed that the addition of vanadium increased the concentration of surface-active carbon species by enhancing CO dissociation and further improved the selectivity of long chain hydrocarbons. However, excess of vanadium increased methane selectivity and decreased C þ 5 selectivity.

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