Catalytic liquid phase oxidation of 1,4-dioxane over a Pt/CeO2-ZrO2-Bi2O3/SBA-16 catalyst

Abstract

Abstract:A Pt/CeO 2 -ZrO 2 -Bi 2 O 3 /SBA-16 (Santa Barbara Amorphous No. 16) catalyst was prepared by hydrothermal and wet impregnation methods for catalytic purification of 1,4-dioxane in water. SBA-16 has a number of mesopores and the average size of the pores is 9.4 nm. In the present catalyst, platinum and CeO 2 -ZrO 2 -Bi 2 O 3 were successfully dispersed in the pores of the SBA-16 support, and the temperature dependence of the liquid phase oxidation of 1,4-dioxane was examined. The oxidation reaction proceeded effectively in the air atmosphere in the temperature range of 40-80 ℃.

High catalytic efficiency in liquid‐phase oxidation of 1,4‐dioxane using a Pt/CeO2‐ZrO2‐SnO2/SBA‐16 catalyst

“…The results are shown in Fig. for comparison with those for Pt/CeO 2 –ZrO 2 –Bi 2 O 3 /SBA‐16 (Pt/CZBi/SBA) and SBA with only Pt loaded as the catalyst (Pt/SBA), which were reported previously . A comparison between Pt/CZSn/SBA, Pt/CZBi/SBA, and Pt/SBA reveals that Pt/CZSn/SBA exhibited the highest catalytic activity for the removal of 1,4‐dioxane.…”

“…The results are shown in Figure 8 for comparison with those for Pt/ CeO 2 -ZrO 2 -Bi 2 O 3 /SBA-16 (Pt/CZBi/SBA) and SBA with only Pt loaded as the catalyst (Pt/SBA), which were reported previously. 16 A comparison between Pt/CZSn/ SBA, Pt/CZBi/SBA, and Pt/SBA reveals that Pt/CZSn/SBA exhibited the highest catalytic activity for the removal of 1,4-dioxane. From the TPR profiles of the Pt/CZSn/SBA and Pt/CZBi/SBA catalysts as shown in Figure 9, the oxygen release peak for Pt/CZSn/SBA appeared at lower temperatures than that for Pt/CZBi/SBA.…”

“…By inserting a Pt catalyst and the CeO 2 –ZrO 2 –Bi 2 O 3 promoter into a pore of the mesoporous silica SBA‐16 (Santa Barbara Amorphous No. 16) with a large surface area, Pt/CeO 2 –ZrO 2 –Bi 2 O 3 /SBA‐16 exhibited a rate of net decrease of 34% after reaction under moderate conditions, i.e., at 80°C for 4 h in an air atmosphere without the supply of any additives or irradiation by UV or ultrasound …”

“…15 exhibited a rate of net decrease of 34% after reaction under moderate conditions, ie at 80°C for 4 h in an air atmosphere without the supply of any additives or irradiation by UV or ultrasound. 16 In this study, to increase the catalytic efficiency for the removal of 1,4-dioxane, we selected a CeO 2 -ZrO 2 -SnO 2 solid solution as the promoter instead of CeO 2 -ZrO 2 -Bi 2 O 3 . In the case of CeO 2 -ZrO 2 -SnO 2 /Al 2 O 3 , high oxygen release and storage abilities were reported owing to a redox reaction between Sn 4+ and Sn 2+ ions at lower temperatures, compared with CeO 2 -ZrO 2 -Bi 2 O 3 /Al 2 O 3 .…”

An NMR study on the mechanisms of freezing and melting of water confined in spherically mesoporous silicas SBA-16

“…These spherical pores are large enough for an ice crystallite to grow from the smallest embryo stage of ~4.0 nm (10,34). Although there have been a number of studies on the utility of chemical reactions as a catalyst (35)(36)(37)(38)(39)(40)(41), it is rare to find detailed studies on the nature of the liquid (42).…”