A PROCESS FOR REDUCING CHLORONITROBENZENE CATALYZED BY PLATINUM-NANOPARTICLES STABILIZED ON MODIFIED MONTMORILLONITE CLAY

摘要

Pt^o-nanoparticles of in the size range 0 - 10 nm were prepared in-situ by impregnation of H₂PtCl₆.6H₂O into the nanopores of modified montmorillonite followed by reduction with different reducing agents like ethylene glycol, sodium citrate, hydrogen, hydrazine and sodium borohydrate. The montmorillonite was modified by activation with mineral acids under controlled condition for generating desired nanopores. XRD pattern of Pt^o-nanoparticles revealed the formation of face centered cubic (fcc) lattice. These supported Pt^o-nanoparticles show efficient catalytic activity for the selective reduction of chloronitrobenzenes. As a typical example, at a H₂ pressure of 10 bars, temperature 45 °C for a period of 15 min, the Pt^o-nanoparticles (prepared by reduction with hydrazine) exhibit conversion of o-chloronitrobenzene upto 100 % and selectivity 99 % to o-chloroanilines with very negligible amount of C-Cl bond cleavage.