(509f) Synthesis and Evaluation of Mesoporous Carbons (Starbons®) from Colombian Cassava As Catalyst for Fatty Acids Esterification.

Fatty acid esters (FAEs) are important oleochemicals used in the manufacture of personal care, pharmaceutical and food products, and they have a global market of around $2.4 billion/yr. FAEs can be produced using mesoporous acid catalysts that enable large molecules to reach active sites, and increasing the reaction yields. In this regard, Starbons® (starch derived mesoporous activated carbons) are promising biobased mesoporous materials that can be activated to be used as catalyst in esterification. Advantageously, the hydrophilic-hydrophobic character of Starbon® can be tuned by mean of controlling the degree of carbonization, thus improving the catalytic properties and the water removal capacity. According to Colombian National Planning Department, nearly 5 Mton of roots and tubers are produced in the country, but nearly 30% are discarded during production stages as they do not meet quality standards. These waste products are still suitable for production of starches, that can be further used as raw material for Starbons®. In this regard, this work focused on the production of Starbon® materials using Colombian starches as feedstock. The material was activated by sulfonation and further evaluated as catalyst in the production of FAEs. Colombian cassava starch was gelated in water, retrograded and freeze-dried to obtain an aerogel structure. Subsequently, the material was carbonized, activated, and finally sulfonated. At each stage, the effect of different operating conditions were asses, such as gelation temperature, molar ratio, carbonization temperature, and sulfonation time. This enabled to define suitable operating conditions to obtain Starbon-type catalysts. The obtained material was characterized by measuring surface area, ion exchange capacity, and pore size distribution. Finally, the obtained catalyst was tested in the esterification of waste fatty acids. The catalyst exhibited better performance and stability than traditional heterogeneous catalysts (e.g. ion exchange resins), with higher yields after several reuse cycles.