LIQUID-PHASE HYDROGENATION OF m-DINITROBENZENE OVER PLATINUM CATALYSTS

Abstract

The m-dinitrobenzene hydrogenation to m-phenylenediamine in liquid phase was studied with platinum supported on SiO 2 , TiO 2 , Al 2 O 3 and Nb 2 O 5 catalysts. Incipient impregnation method was used to prepare the catalysts with 1wt% of Pt. The effect of the support and the reduction temperature (473 K or 773 K) were analyzed. The materials were characterized by X-ray diffraction (XRD), nitrogen physisorption (77 K), hydrogen chemisorption (298 K), transmission electron microscopy (TEM), temperature programmed reduction (H 2 -TPR) and temperature programmed desorption of ammonia (NH 3 -TPD). The results showed that Pt/ TiO 2 (HT) catalyst had a higher yield (60%) toward m-phenylenediamine and conversion level (98.2%) of m-dinitrobenzene. This behavior can be attributed to the reduction of PtO x crystallites to metallic Pt, small particle size and the strong metal-support interaction due to the migration of TiO x species on the Pt crystallites.

Steady‐State, Scalable Production of Mesoporous Rutile and Brookite Particles and Their Use in Energy Conversion and Storage Cells

“…This was confirmed by BET analysis; for powders obtained at steady‐state at 0.1 m and 0.5 m TiCl 4 solutions (Figure S4) the BET adsorption/desorption isotherms show hysteresis loops and thus are classified as IUPAC Type IV, typical of mesoporous adsorbents . Figure S4 b) shows type H2 hysteresis loop indicating presence of small spherical particles and bottleneck pores …”

Acidic ionic liquid immobilized on nanoporous Na+-montmorillonite as an efficient and reusable catalyst for the formylation of amines and alcohols

“…5a. Both samples exhibited a type V isotherm with H 3 hysteresis loop categories according to the literature [32], which indicates the micro-and mesopore structures of samples with slit-like pores [33]. These results also prove that the textural properties of Na ?…”

One-pot synthesis of 4,4ʹ-(arylmethylene)-bis-(3-methyl-1-phenyl-1H-pyrazol-5-ols) catalyzed by Brönsted acidic ionic liquid supported on nanoporous Na+-montmorillonite

“…6a. Both samples exhibited type V isotherm with H 3 hysteresis loop categories according to the literature [34], which indicates the micro and mesopore structures of samples with slit-like pores [35]. These results also prove that the textural properties of Na + -MMT were substantially maintained over immobilization of ionic liquid.…”