Preparation of Polyurethane Foams Based on Maltodextrin and Their Potential Use in Methyl Ester (Biodiesel) Purification

Biodiesel can be obtained by transesterification of the triglycerides present in the vegetable oil and animal fat. After the reaction it is necessary to purify the alkyl esters. One way to obtain this is making the dry wash. Thus, this study proposes the preparation of polyurethane foams with maltodextrin as sorbents for use in the biodiesel purification. The foams were prepared and characterized by ATR-FTIR, TGA, DSC and water absorption test (ASTM D570). The FTIR spectra showed typical bands of polyurethane, TGA curves showed weight loss in two stages, the DSC analysis of the foams based on maltodextrin revealed a Tg value higher than that observed for the control foam, moreover, the absorption test in water showed that the foams based on maltodextrin showed a more hydrophilic character. The efficiency of the foams as possible sorbents for biodiesel purification was monitored by two indicators: soap concentration (AOCS Cc 17-19) and acidity index (AOCS Ca 5a-40). The results indicated that the foams were promising candidates in the removal of contaminants.