One‐Pot Synthesis of Potassium‐Functionalized Mesoporous γ‐Alumina: A Solid Superbase

Abstract

In einem Arbeitsgang: Mesoporöse Kalium‐γ‐aluminiumoxid‐Superbasen, die sich durch eine hohe Basestärke von 27.0 und eine gut ausgeprägte mesoporöse Struktur auszeichnen, sind effiziente Katalysatoren in der Isomerisierung von 1‐Hexen. Ihre einfache Synthese in einem Eintopfprozess beruht auf der flexiblen Verwendung von K2CO3 zur pH‐Justierung und einer kontrollierten Kalzinierung (siehe Bild).

Significant Decrease in Activation Temperature for the Generation of Strong Basicity: A Strategy of Endowing Supports with Reducibility

“…45 All samples containing KNO 3 give an obvious IR band at 1384 cm −1 attributed to N−O vibration. 46,47 After activation at 400 °C, the sample 30KCA(1)-400 still has a strong vibration band of nitrate, which indicates that KNO 3 is only partially converted. 48,49 For the KCA(2)-400 series samples, the band of nitrate drops sharply, and there is only a peak left at 1384 cm −1 derived from the support, which indicates the entire conversion of KNO 3 in the presence of sufficient Cr in the supports (Figure S11).…”

Efficient Transformation of Waste Bone Oil into High Quality Biodiesel via a Synergistic Catalysis of Porous Organic Polymer Solid Acid and Porous γ-Al2O3-K2O Solid Base

“…In general, the increasing of the concentration of active sites usually results in the decreased BET surface areas in the samples. [27][28][29][30][31]33 Figure 1C showed the FT-IR data for the H-PDVB-SO 3 H. The peaks near 620 and 1092 cm −1 are related to the SO and SO bonds. 21 Also, the weak peak at 1042 cm −1 was assigned to the formation of the CS bond.…”

“…Notably, the peaks associated with the cubic structure of γ-Al 2 O 3 -K 2 O could be clearly observed (Figure 2A), in good agreement with the literature results. 29,30 After treatment with KF, and a second calcination, a weak peak at around 2θ = 42.7°w as observed, which was assigned to the presence of K 2 O, indicating the transformation of KF into K 2 O during the calcination process. 30,31,33 The above results demonstrated that the K 2 O active site has been successfully loaded into mesoporous γ-Al 2 O 3 .…”

“…The recyclability results are comparable with a previously reported study for γ-Al 2 O 3 -K 2 O catalyzed transesterification of pure triglycerides, where the catalyst was prepared with a more difficult procedure with the sol−gel method. 29 Verziu et al used γ-Al 2 O 3 -K 2 O solid base for transestrification of sunflower oil and with microwave heating. 31 The oil conversion decreases from 98 to 57% after 6 runs at a temperature of 75 °C and 120 min reaction time.…”

Low-cost and effective phenol and basic dyes trapper derived from the porous silica coated with hydrotalcite gel

“…The basic strength of sample was measured by means of Hammett indicator as described previously [22], while the total basicity was determined by conventional titration [23]. In a typical NH 3 -TPD or CO 2 -TPD experiment, the sample was activated at 873 K for 2 h prior to adsorption of NH 3 or CO 2 at 298 K. After the physical adsorbed CO 2 was purged by carrier gas flow at 298 K for 1-2 h, the sample was heated to 773 K at a rate of 8 K min À1 , meanwhile the liberated NH 3 or CO 2 was detected by an on-line Varian 3380 gas chromatograph [24].…”