(509d) Optimization of Reaction Conditions in the Epoxidation and Hydroxylation of High-Oleic Palm Oil

Colombia is a major producer of palm oil with a current annual production of around 1.6 million tons, which is mostly used in the food industry (58%) and in the manufacture of biodiesel (33%). However, during last years this agricultural sector has been suffering by large crop losses caused by the bud rot disease. As a result, growers associations started to develop and implement a more resistant hybrid specie obtained by crossing Elaeis guineensis y Elaeis oleifera. This hybrid exhibits a higher productivity, and the obtained vegetable oil has a higher content of oleic acid within the trialcyl glycerides.

The higher content of unsaturated fatty acid chains confers this oil suitable properties for further valorization, in particular, it could be used as feedstock in the production of epoxides and polyols, which have a large demand in the manufacture of polymers and resins.

Polyols are produced from vegetable oils by epoxidation of the double bounds in the unsaturated fatty acid chains, followed by hydroxylation with a proton donor. Epoxidation is generally carried out by mean of reaction with H₂O₂, with acid catalysts. Under these conditions, water can drive oxirane ring opening resulting in polyols with less reactive secondary hydroxyl groups. Generally, polyols with primary hydroxyl groups are commercially referred, so there is need to reduce the simultaneous ring opening reaction and to improve selectivity towards the epoxide. In this regard, a simplex algorithm was experimentally implemented to identify the operating conditions that improve conversion and that maximize the oxygen oxirane content.

In a subsequent stage, and to assess the main characteristics of natural oil polyols (hydroxyl value, molecular weight, viscosity, functionality), different ring opening agents were used during hydroxylation, namely diethylene glycol, ethylene glycol and glycerol. Simplex algorithm was used to enhance the reaction yield and the hydroxyl value.