High pressure processing of vegetable oils and derivatives to obtain value-added products

COTABARREN, N.; SOTO, G.; HEGEL, P.; PEREDA, S.

Rosario

Congreso; World congress on oils and fats; 2015

ASAGA

High pressure technology has been emerged in the last years as an interesting alternative to transform the concept of chemical plants and lead to compact, safe, energy-efficient, environment-friendly sustainable processes. The supercritical fluid extraction for example has been commercially proven for the processing of natural products in order to obtain value-added products. The continuous non-catalytic supercritical alcohol transesterification technology is another interesting high pressure process useful to obtain biodiesel and acylglycerol derivatives from non-edible vegetable oil, waste cooking oils, and oil by-products. This technology has several advantages including high production efficiency and environmentally friendliness. Second generation oil-based biorefineries are aimed to enrich any residue with oil content. For example, the great increase of worldwide production of soybean and sunflower oil, impacted not only in the oil market but also in the oil refining by-products (phospholipids sludge and distillates of the deodorizer), which prices are rapidly changing, and because of the high production volume of vegetable oils this by-products are becoming a waste with disposal-associated problems. An alternative sustainable technology for this by-product is the direct alcoholysis of phospholipids and vegetable oil (triglycerides) occluded in the wet gum using high pressure supercritical ethanol to produce fatty acids ethyl esters (FAEE) and derivatives. On the other hand, acylglycerols are high added-value products derived from vegetable oil. They are common food emulsifiers and surface active agents in many industrial cleaning products. Commercial MG is obtained via an alcoholysis pathway in which either fatty acids or a fat are reacted with an excess of glycerol. The conventional process is expensive and recovers only part of the produced MGs, in addition high purity cannot be reached due to thermal degradation of products and raw materials. An alternative pathway of synthesis is needed to improve the atomic efficiency of the purification process. Acylglycerols can be economically produced in biodiesel processing plants, carrying out an incomplete transesterification of vegetable oil. Moreover, the purification of MG from a mixture of biodiesel can be carried out with pure CO2 as a green solvent. Additionally, high purity fatty esters free of tinctures can be obtained also in the CO2 separation process.In this presentation, sustainable technologies for residues processing and vegetable oil recycling will be discussed. Moreover, also a high pressure technology for high purity fatty esters and monoglycerides recovery will be presented. Integration of the discussed technologies may contribute to pave the way towards oil-based second generation biorefinery development.