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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.

Two plate-type anodic alumina supported Ru catalysts, Ru/Al and Ru/Ce–Al, has been employed to investigate activities in the kerosene steam reforming reaction. H2 pre-reduction during the kerosene steam reforming was found not an essential procedure, in terms of activity and stability. In addition, the Ru/Ce–Al catalyst was more stable than Ru/Al without pre-reduction in the accelerated life test. In the 20 times of DSS operation over Ru/Ce–Al, no remarkable decline in kerosene conversion was observed, indicating that Ru/Ce–Al was tolerable to multiple cycles under such severe conditions without obvious deterioration. Under an electric heating pattern, the performance of catalyst Ru/Ce–Al was investigated. It showed that 100% of kerosene conversion would be obtained in just 15 min over the Ru/Ce–Al catalyst when the kerosene was introduced into the reactor. It also presented excellent stability during test and DSS operation, which indicates more promising lifetime for the Ru/Ce–Al catalyst in the wall-type reformer.

Plate-type metal monolithic anodic alumina supported Ru catalysts prepared by impregnation method has been employed for the kerosene steam reforming. The characteristics of the catalysts were analyzed by ICP, BET, TG and FESEM. We found that although plate-type Ru/Al2O3 catalyst displayed favorable activity in the long-term stability test, coke deposition resistance should be further improved. In order to inhibit the coking during the reforming reaction, ceria was added to Al2O3 support to synthesize Ru/Ceria-Al2O3 catalysts. The results showed that ceria addition to the Ru/Al2O3 catalyst enhanced the catalyst stability, resulting from the lower content of coke formation on the catalyst surface. Furthermore, it showed that the content of ceria had a greater impact on the content of coke formation on the catalyst surface. If more ceria were contained in Ru/Ceria-Al2O3 catalyst, less coke would be formed over the catalyst surface during the reaction.

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.