Effects of Structured Solids on Regioselectivity of Dibromination of Naphthalene

The influence of structured solids (amorphous, lamellar and 3D crystalline) on the regioselectivity of the dibromination of naphthalene using bromine at room temperature has been investigated. The more acidic amorphous catalysts and an acidic clay give rapid reactions and lead to a large preponderance of 1,4-dibromonaphthalene over the 1,5-dibromo compound, while calcined KSF clay, a bentonite material, after a short reaction time gives a small predominance of the 1,5-isomer. Longer reaction times lead to the equilibration of reaction mixtures, which means that the 1,4-isomer eventually predominates in all cases. Based on these observations, it has been possible to devise synthetically useful preparative procedures, involving direct room temperature reactions of bromine with naphthalene, for either 1,4-dibromonaphthalene or 1,5-dibromonaphthalene based on the use of different solids, namely Synclyst 13 and KSF clay, respectively.

Epoxidation of 1-octene under harsh tail-end conditions in a flow reactor I: a comparative study of crystalline vs. amorphous catalysts

The crystalline Ti-UCB-4 epoxidation catalyst is more active, selective, and stable than the amorphous Ti–SiO2.

Mapping the performance of amorphous ternary metal oxide water oxidation catalysts containing aluminium

Ternary amorphous catalysts containing varying stoichiometries of aluminium, iron, nickel and/or cobalt for the oxygen evolution reaction (OER) were mapped out to define the optimal composition for mediating oxygen evolution from water.

Highly selective catalytic hydrodeoxygenation of Caromatic–OH in bio-oil to cycloalkanes on a Ce–Ni–W–B amorphous catalyst

Ce–Ni–W–B amorphous catalysts exhibited high activity in the hydrodeoxygenation (HDO) of Caromatic–OH. The deoxygenation degree was up to 98.1% with low aromatics selectivity at 498 K. Both the aromatics content and reaction temperature were decreased, which realized the energy saving and consumption reduction in the HDO process.