Phase equilibria fenomena in fatty oil transesterification with supercritical alcohols

PABLO HEGEL; GUILLERMO MABE; SELVA PEREDA; ESTEBAN A. BRIGNOLE

Iguassu Falls

Congreso; I IBEROAMERICAN CONGRESS ON SUPERCRITICAL FLUIDS; 2007

Recent experimental studies on non-catalytic transesterification, have shown tha high reaction rates, which justify the comercial applications of this process, can be obtained if the operating conditions are above the critical temperature and pressure of metanol. Even thogh that is generally agreed that temperatures above 550K and high metanol/oil ratios are required to obtain high convertions and high reactions rates, there is disagreement among the differents authors regarding the operating pressure, the assumed phase conditions, the use of co-solvents and the justification of sudden increase of rate of reaction with temperature. In the present work, the reaction process and its phase transitions characteristics are directly observed in a double window cylindrical reactor and the convertion in methyl esters is measured. From direct observations and the modelling of the phase behavior, a better understanding of the supercritical metanol transesterification process is obtained.