Insight in the Alginate Pd-IonogelsApplication to the Tsuji–Trost Reaction

A new class of catalytic ionogels based on the entrapment of an ionic liquid phase within a sodium alginate matrix was applied to the Pd-catalyzed allylic substitution reaction. High activity and promising recyclability were obtained in C–N bond formation. Scanning electron microscopy, scanning transmission electron microscopy, and solid-state NMR studies provided a better insight into the catalytic behavior, and the stability of the catalytic ionogels was studied through a recycling process

Inhibition of Palm Oil Oxidation by Zeolite Nanocrystals

The efficiency of zeolite X nanocrystals (FAU-type framework structure) containing different extra-framework cations (Li⁺, Na⁺, K⁺, and Ca²⁺) in slowing the thermal oxidation of palm oil is reported. The oxidation study of palm oil is conducted in the presence of zeolite nanocrystals (0.5 wt %) at 150 °C. Several characterization techniques such as visual analysis, colorimetry, rheometry, total acid number (TAN), FT-IR spectroscopy, ¹H NMR spectroscopy, and Karl Fischer analyses are applied to follow the oxidative evolution of the oil. It was found that zeolite nanocrystals decelerate the oxidation of palm oil through stabilization of hydroperoxides, which are the primary oxidation product, and concurrently via adsorption of the secondary oxidation products (alcohols, aldehydes, ketones, carboxylic acids, and esters). In addition to the experimental results, periodic density functional theory (DFT) calculations are performed to elucidate further the oxidation process of the palm oil in the presence of zeolite nanocrystals. The DFT calculations show that the metal complexes formed with peroxides are more stable than the complexes with alkenes with the same ions. The peroxides captured in the zeolite X nanocrystals consequently decelerate further oxidation toward formation of acids. Unlike the monovalent alkali metal cations in the zeolite X nanocrystals (K⁺, Na⁺, and Li⁺), Ca²⁺ reduced the acidity of the oil by neutralizing the acidic carboxylate compounds to COO^–(Ca²⁺)_1/2 species