Sulfonation of the surface of cordierite monoliths through a novel multi-step wet chemical process

A new reactivation method towards deactivation of honeycomb ceramic monolith supported cobalt–molybdenum–boron catalyst in hydrolysis of sodium borohydride

“…ICP analysis of the supernatant after each cycle and washing demonstrated that neither Co nor Mo was detected, indicating no leaching of active components over the course of reaction or washing. Based on the results reported by Akdim et al in their study of the Co-based catalyzed NaBH 4 system [26], the reactivity deterioration could be attributed to the precipitation/adsorption of borate species on the surface of catalyst. The deactivation also occurs when dipping an asprepared catalyst in a 5 wt% NaBO 2 solution for 30 s. This may be seen as an evidence of adsorption of the boron-contained species on the catalyst surface.…”

“…In the present study, the selected HCM, which is composed of Al 2 O 3 $2MgO$5SiO 2 , has about 400 channels per square inch. Before usage, a piece of HCM of 25 mm in diameter and 10 mm in length was etched via acidic and alkaline treatments according to the procedure described by Galindo et al [26]. The appropriate acidic/alkaline treatments induced a selective leaching of a portion of Mg, Al and Si oxides from the support surface, building a rough and porous surface, and promoting the stability of ceramic support in alkaline medium.…”

Catalytic Esterification Using Solid Acid Carbon Catalysts Synthesized by Sustainable Hydrothermal and Plasma Sulfonation Techniques

“…The band between 1000 and 1300 cm –1 is characteristic of phosphorylated carbons and attributed to stretching vibrations of hydrogen bonded PO, OC stretching in POC linkage, and to POOH. , The hydrothermal (cACM-HT-2M) and plasma treated ACM (cACM-PT-Ar/H 2 O-10 min) show a distinct peak at 1059 cm –1 attributed to SO stretching vibrations of −SO 3 H groups; OS stretching at 1042 cm –1 is reported in a sulfonated graphene oxide monolith . Peaks at 1030 and 1210 cm –1 are attributed to symmetric and asymmetric stretching vibrations of the SO 3 –1 group, respectively . The peak at 1188 cm –1 has also been assigned to SO symmetric stretching vibration and the peaks at 1036 cm –1 assigned to SO and SO 3 2– stretching vibrations, respectively. , …”

“…35 Peaks at 1030 and 1210 cm −1 are attributed to symmetric and asymmetric stretching vibrations of the SO 3 −1 group, respectively. 36 The peak at 1188 cm −1 has also been assigned to SO symmetric stretching vibration and the peaks at 1036 cm −1 assigned to SO and SO 3 2− stretching vibrations, respectively. 37,38 Because −SO 3 H signatures, especially in the sulfonated GAC catalysts, were not clear, XPS analysis was performed (Figure 5, Table S2).…”

“…Similar results were observed with a carbon catalyst synthesized using concentrated sulfuric acid under reflux (150 °C, glycerol conversion of 76% after 5 h). 36 For all reactions, the carbon recovery was above 90%. About 5−10% of the recovered carbon in terms of percent peak area were two unknowns (retention times of 1.76 and 7.1 min).…”