Catalytic esterification via silica immobilized p-phenylenediamine and dithiooxamide solid catalysts

Abstract

The p-phenylenediamine (PDA) and dithiooxamide (DTO) were immobilized onto silica from rice husk ash (RHA) using 3-chloropropyltriethoxyilane (CPTES) to form a solid catalyst denoted as RHAPDA and RHADTO, respectively. BET measurements of the catalysts showed the surface area to be 145 and 9.7 m2 g−1 with an average pore diameter of 9.8 and 10.9 nm, respectively. The catalytic performance of RHAPDA and RHADTO was tested in the esterification of ethyl alcohol with acetic acid. A conversion of 48% and 69% was achieved, respectively with 100% selectivity toward ethyl acetate.

Keywords

• Rice husk ash
• Surface modification
• Dithiooxamide
• p-Phenylenediamine
• Esterification