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Rapidly deactivation of Cu/SiO2 catalysts at high liquid hour space velocity (LHSV) has been an important obstacle for scale-up application. Herein, silver modified copper phyllosilicate nanotubes were fabricated by different strategies, and implemented to the selective hydrogenation of ethylene carbonate (EC) to methanol and ethylene glycol (EG) as alternative route for the indirect utilization of CO2. The CuPs Ag–copre catalyst synthesized by the co–ammonia evaporation hydrothermal process achieved 79% methanol and 99% EG yield within various ranges of EC LHSV, which was attributed to the balanced Cu+/Cu0 ratio and the enhanced H2 dissociation ability. Inlaid silver species over copper phyllosilicate promoted the interaction between the metal and the support, which substantially regulated the reducibility and dispersion of copper species, meanwhile, increased the stability for long-term running of the catalyst.

Various Cu/CeO2 nanorod catalysts with different copper content were synthesized through a facile coprecipitation method for the hydrogenation of diethyl carbonate to methanol in a fixed-bed reactor. The methanol yield enhanced with increasing of copper loading, but excessive amount of copper would lead to the deactivation of catalyst at higher liquid hourly space velocity because of the active metal aggregation. The 20Cu/CeO2 and 30Cu/CeO2 catalyst displayed superior catalytic performance with the methanol space-time yield of 8.4 and 8.1 mmol·gcat−1·h−1, respectively. The remarkably enhanced catalytic performance was mainly ascribed to higher Cu0 surface area, appropriate ratio of Cu+/Cu0 and more surface oxygen vacancies associated with Ce3+, which stemmed from the strong interaction between Cu and the CeO2 support.

A plate-type anodic alumina support (γ-Al2O3/Fe–Cr–Ni alloy/γ-Al2O3) was used to prepare a series of Ru catalysts. The performance of these catalysts was investigated in the steam reforming of kerosene (SRK). Ethanol solution impregnation was used to enhance metal dispersion on the catalyst surface. The catalyst prepared by ethanol solution impregnation and dried at 120 °C (Ru/Al2O3-ED) gave a higher metal dispersion and more favorable activity and durability than that prepared in aqueous solution. However, owing to shrinking caused by the oxidation of ruthenium species, high temperature calcination in air after impregnation greatly decreased the metal dispersion on the catalyst surface, regardless of the impregnation solution type. In contrast to calcination in air, high temperature N2 treatment could decompose the reducible ruthenium species on the Ru/Al2O3-ED completely. This indicates that H2 pre-reduction is not an essential procedure for the SRK reactions over this catalyst. The experimental results also confirm this hypothesis. The effect of Ce addition was also investigated and was found to enhance significantly the catalyst tolerance to carbon deposition thereby improving the SRK durability of Ru/Al2O3-ED under a high space velocity. In addition, owing to the high electrical resistance of the Fe–Cr–Ni alloy, the anodic alumina catalyst itself can be used as a heater, when an electrical current is applied along the alloy layer. Under an electrical-heating pattern, the SRK reaction system reached stability within 15 min, offering a strong possibility for shortening the start-up time of conventional reformers from 1 to 2 h to a few minutes.

An anodic alumina supported silver catalyst (1.7 Ag/Al2O3) was synthesized to investigate the selective catalytic reduction (SCR) of NO under an electrically heating pattern. It was found that less than 1 min was required to heat the catalyst from room temperature to 450°C. Comparing with a common furnace heating pattern, similar de-NOx activity was achieved. According to the electrically heating tests, the NOx conversion of 1.7 Ag/Al2O3 remained above 80% for 15 h at 450°C (F/W = 65000 mL/(g · h)), which proved that it was commendable to apply this type of catalyst to C3H6-SCR of NO. Additionally, the promotional effect of hydrogen additive is also discussed under the electrically heating pattern. In the presence of 2000 ppm of hydrogen, the 1.7 Ag/Al2O3 reached 80% NOx conversion within a few seconds at 300°C, while the activity was very low at 300°C without hydrogen; such a high conversion was maintained for 15 h.

A series of anodic alumina supported silver/titanium catalysts (Ag/Ti/Al2O3) were synthesized to investigate the effect of Ti on the selective catalytic reduction of NO with propene. In the low temperature region, the SCR activity was greatly enhanced on Ag/Ti/Al2O3 compared to Ag/Al2O3, and this promotion became more significant with increasing Ti loading. Adding Ti to an anodic alumina support did not cause obvious improvement of activity, indicating that the presence of Ti acted as a catalytic promoter of Ag, but did not directly participate in the SCR reaction. The result of NOx-TPD in flowing He showed that no obvious difference in the desorption performance of ads-NOx species was found between Ag/Al2O3 and Ag/Ti/Al2O3. However, in flowing O2/C3H6/He the desorption peak of nitrate species was decreased by about 50°C when Ti was present. The promoted partial oxidation of the reducing agent was believed to be a main reason. The result of H2-TPR suggested that besides Ag+ ion and metallic Ag another type of silver existed in Ag/Ti/Al2O3, possibly a moderately agglomerated Agnδ+ cluster. Additionally, in comparison with the SO2-aged Ag/Al2O3 catalyst, the SO2-aged Ag/Ti/Al2O3 catalyst provided a favorable tolerance to SO2 poisoning, and led to higher activity. A relatively lower SO2 adsorption amount and a faster reduction rate of sulfate species by propene were considered to be a reasonable interpretation.

A novel metal monolithic anodic γ-Al2O3 support was prepared by anodization using a clad aluminum plate. The catalytic combustion of methane on Pt/Al2O3/Alloy, Pd/Al2O3/Alloy and Pd–Pt/Al2O3/Alloy catalysts prepared by the impregnation method was studied. The catalysts were characterized by ICP, BET, and temperature-programmed oxidation (TPO). The results showed that at low temperatures ( 700°C), Pd–Pt/Al2O3/Alloy showed the best activity among these three catalysts, whereas the activity of Pd/Al2O3/Alloy decreased gradually. Therefore, it was concluded that the co-existence of Pd and Pt in the Al2O3/Alloy support in Pd–Pt/Al2O3/Alloy made its activity the best among that of all the catalysts studied over the entire temperature range (400–800°C) considered for methane combustion.

An anodic alumina supported 17.9 wt% Ni catalyst shows an excellent catalytic performance during steam reforming of methane at 700°C under W/F = 6.33 × 10–3 g-cat·h/L, even when compared with some commercial Ni and Ru reforming catalysts. This is considered to be the result of the existence of an interfacial NiAl2O4 layer, which could anchor the top metallic nickel particles to prevent them from reacting with the alumina support and sintering, thereby, effectively suppressing carbon deposition. Nevertheless, for the industrialization of anodic nickel catalysts, some effort should be made to alleviate the deterioration of anodic supports, because when subjected to a higher W/F as 1.27 × 10–3 g-cat·h/L, the catalyst shows irreversible deactivation, and little improvement is seen by increasing nickel spinel content and metal loading or modifying the impregnation solution pH.

A 17.9 wt.% Ni/Al 2 O 3 /alloy catalyst with porous anodic alumina support was subjected to steam reforming of methane after 700 °C steam purging and no reactivity was shown because of surface oxidation of sintered Ni particles. When 0.05 wt.% Ru doped on this catalyst, it exhibited self-activation and self-regenerative activity, resulted from the hydrogen spillover over Ru and/or Ru–Ni alloy. Moreover, a 97% CH 4 conversion was kept for 20 h over the catalyst under electrical heating pattern.

A series of plate-type metal-monolithic anodic alumina supported nickel catalysts were employed to investigate their reactivity in the steam reforming of methane reactions. After H2 reduction, a fresh 4.7 wt% Ni/γ-Al2O3/alloy catalyst provided only a short-term activity, and then deactivated quickly. By the temperature programmed reaction technologies, the oxidation of surface sintered metallic Ni particles in the SRM test was suggested to be the main reason for the catalyst deactivation. As a result, a 17.9 wt% Ni/NiAl2O4/γ-Al2O3/alloy catalyst with an interfacial NiAl2O4 layer was synthesized, which showed excellent SRM reactivity at 700 °C and this was believed to be resulted from the existence of interfacial NiAl2O4 layer which anchored the top metallic nickel particles and effectively suppressed catalyst sintering. Moreover, no unfavorable effect was evidenced over the SRM reactivity of anodic Ni catalysts when applying the electrically heated pattern. Nevertheless, for the industrialization of anodic nickel catalysts, some efforts should be made to alleviate the deterioration of anodic supports and the catalysts sintering under the SRM reactions.