(337a) Biodiesel Produced from Soybean Oil with the Two Flow Reactors in Series

Authors: 
Baah, D. - Presenter, Tuskegee University
Vahdat, N., Tuskegee University

Viscous vegetable oils
containing triglycerides of various fatty acids and free fatty acids are mostly
converted to less viscous fatty acid methyl esters (FAME) through the methanol
trans-esterification process, using homogeneous catalysts in batch reactors. FAME
biofuels produced with homogeneous alkali catalysts through transesterifcation
processes contain undesirable substances such as soap and homogeneous catalysts
in addition to glycerol and water.  Additional
refining and purification processes are needed to remove these undesirable
substances from FAME biofuels, generating wastewater.  In our research, viscous soybean oil is
converted to less viscous FAME biofuels with methanol and honeycomb monolithic catalysts
in a two-flow reactor assembly in series at moderate temperatures and pressures
to develop monolithic catalysts for efficient methanol transesterification
processes.

Reaction mixtures from
the first catalytic flow reactor consist of biodiesel (fatty methyl esters),
glycerol, unreacted soybean oil, and excess methanol.  Glycerol is removed from reaction mixtures
from the first catalytic flow reactor to feed the second catalytic flow reactor.  Reaction mixtures of biodiesel and unreacted
soybean oil produced from the first catalytic flow reactor are fed into the
second catalytic flow reactor to increase yields of biodiesel by shifting
equilibrium conversion of soybean oil in favor of increasing conversion of
soybean oil into biodiesel.  Active and
stable monolithic catalysts are formulated with various active metals and
honeycomb monolithic catalyst supports to produce FAME biofuels from soybean
oil.