Sulfonated and cross-linked polystyrene ultrafine fibers for the esterification of palmitic acid for biodiesel production

摘要

For the need of green and sustainable development, a fibrous solid acid catalyst was developed for the transformation of low cost oils to biodiesel in an efficient and green manner. Polystyrene was electrospun into ultrafine fibers with mean diameter of similar to 1.34 mu m, and then simultaneously cross-linked and sulfonated in sulfuric acid/acetic acid mixed solvent with paraformaldehyde as the external cross-linker. The cross-linking and sulfonation degrees were controllable by changing the ratio of sulfuric acid/acetic acid. After sulfonation and cross-linking, the solvent resistance, chemical structure, and composition of these fibers were separately characterized by scanning electron microscopy, infrared spectroscopy, and elemental analysis. At last, this novel fibrous solid acid catalyst was used to catalyze the esterification reaction of palmitic acid and methanol for biodiesel production. After optimizing the reaction conditions, this fibrous solid acid catalyst can catalyze the esterification of palmitic acid and methanol with the conversion up to 92% under mild reaction conditions. Moreover, due to the fibrous structure, this fibrous solid acid catalyst could be readily separated and reused.