Fundamental and applied research on clay minerals: From climate and environment to nanotechnology

Silica coated magnetic Fe3O4 nanoparticles supported phosphotungstic acid: a novel environmentally friendly catalyst for the synthesis of 5-ethoxymethylfurfural from 5-hydroxymethylfurfural and fructose

A nanocomposite able to function as a hydrogenation catalyst under strongly acidic conditions without the presence of noble metals is synthesized and thoroughly studied. This specially designed catalyst possesses a unique structure composed of carbon nitride (CN) with underlying nickel, in which the nickel endows the CN with new active sites for hydrogen adsorption and activation while it itself is physically isolated from the reactive environment and protected from poisoning or loss. The CN is inert for hydrogenation without the help of nickel. The catalyst shows good performance for hydrogenation of nitro compounds under strong acidic conditions, including the one-step hydrogenation of nitrobenzene in 1.5 M H2SO4 to produce p-amoniophenol, for which the acid in the reaction system has restricted the catalyst only to noble metals in previous studies. Further characterization has demonstrated that the nickel in the catalyst is in an electron-deficient state because some of its electron has been donated to...

Acid-Resistant Catalysis without Use of Noble Metals: Carbon Nitride with Underlying Nickel

Superparamagnetic γ-Fe2O3 nanoparticles as an easily recoverable catalyst for the chemical recycling of PET

Conversion of cellulose to lactic acid catalyzed by erbium-exchanged montmorillonite K10

Metal cation-exchanged montmorillonite clay as catalysts for hydroxyalkylation reaction

Acidity tuning of montmorillonite K10 by impregnation with dodecatungstophosphoric acid and hydroxyalkylation of phenol

A novel application of phosphotungstic acid, H3PW12O40 (PWA) supported on MCM-41 molecular sieve as a solid acid catalyst has been demonstrated for the synthesis of phenolphthalein by hydroxyalkyla...

MCM-41 Supported Phosphotungstic Acid for the Hydroxyalkylation of Phenol to Phenolphthalein

The catalyst activity of various solid acids, such as fumed silica (SiO 2 ), dodecatungstophosphoric acid (DTP), DTP impregnated on SiO 2 , amberlyst-15 and montmorillonite KSF/0, was studied for the hydroxyalkylation of phenol to bisphenol F. A well-dispersed DTP on SiO 2 catalyst was prepared by the wet impregnation method. The effect of DTP loading on SiO 2 was also compared with bulk DTP and other solid acid catalysts. 20% DTP/SiO 2 catalyst gave the highest products yield of 34.2% and selectivity of 90.1% to bisphenol F, at 353 K and with a phenol-to-formaldehyde mole ratio of 5:1. Ammonia TPD studies of various catalysts showed that an appropriate combination of both strong and weak acid sites of DTP/SiO 2 was mainly responsible, rather than only the stronger acidity of bulk DTP, for its highest catalytic activity and selectivity. The effect of various reaction parameters like mole ratio, catalyst concentration, temperature and reaction time on product yield and bisphenol F selectivity was also investigated. The catalyst recycle was established by catalyst activity testing.

A.C. Garade

Papers

Metal cation-exchanged montmorillonite clay as catalysts for hydroxyalkylation reaction

Acidity tuning of montmorillonite K10 by impregnation with dodecatungstophosphoric acid and hydroxyalkylation of phenol

MCM-41 Supported Phosphotungstic Acid for the Hydroxyalkylation of Phenol to Phenolphthalein

Selective hydroxyalkylation of phenol to bisphenol F over dodecatungstophosphoric acid (DTP) impregnated on fumed silica

Αn efficient γ-Fe2O3 catalyst for liquid phase air oxidation of p-hydroxybenzyl alcohol under mild conditions