Formulation of Honeycomb Heterogeneous Monolithic Catalysts for the Production of Biodiesel Fuels From Vegetable Oils

Crude vegetable oils containing triglycerides of various fatty acids and free fatty acids are very viscous and have low heating values. Transesterification techniques are used to reduce viscosity of crude vegetable oils and increase their heating values compatible with petroleum diesel fuel.  Biodiesel fuels produced via transesterifcation processes with homogeneous alkali catalysts contain undesirable substances such as soap and homogeneous catalysts in addition to glycerol and water.  Various unit operations are needed to remove these undesirable substances from biodiesel so that production costs of biodiesel are incompatible with those of petroleum diesel.  Biodiesel is produced with feedstocks such as methanol and canola oil chosen as a representative vegetable oil, using honeycomb monolithic heterogeneous catalysts at moderate temperatures and pressures.

Production of biodiesel from vegetable oils has renewed interest in growing canola as a energy crop. The canola seed yields 40 percent oil and the leftover meal is used in poultry and livestock feed.  Canola is an excellent rotation crop because it has deep root systems that scavenge well for water and nutrients. Canola crop uses planting and harvesting equipment similar to what is used for the production of small rotational crops such as soybean, wheat, and cotton.

Triglycerides in vegetable oils should be processed economically via transesterification to improve their properties as biodiesel fuels compatible with petroleum diesel. Crude canola oil is transesterified with methanol and formulated monolithic catalysts, using a honeycomb monolithic catalyst flow reactor.  Efficient monolithic catalysts are proposed to be formulated with various active metals and honeycomb monolithic catalyst supports to reduce viscosity and improve heating values of biodiesel from crude canola oil via a transesterification process.

Flow reactors with honeycomb monolithic catalysts have some advantages over flow reactors packed/fluidized with catalyst pellets for the transesterification of vegetable oils.  Pressure drops will be lower over flow reactors with monolithic catalysts than those packed with pellet catalysts.  High mass transfer rates of methanol and vegetable oils to porous surface of solid catalysts will occur in channels of monolithic catalysts in comparison with packed catalyst pellets.

The objective of this proposed research is to formulate heterogeneous honeycomb monolithic catalysts for the production of biodiesel via efficient transesterification of vegetable oils with the following specific aims:

1. Formulate honeycomb monolith catalysts for the conversion of vegetable oils to biodiesel.

2. Design and fabricate a small-scale honeycomb monolithic catalyst flow reactor assembly for the conversion of vegetable oils to biodiesel.

3. Produce biodiesel in a fabricated small-scale honeycomb monolithic catalyst flow reactor at various operation conditions, and generate transesterification data for the evaluation of formulated monolithic catalysts.

4. Regenerate deactivated honeycomb monolithic catalysts for the production of biodiesel.