Synthesis of bioethanol from mixed vegetable wastes: Experimental methodology and characterization

Bioethanol has been identified as a renewable product with high potential for application as biofuel. On the other hand, high volumes of agri-food residues are generated daily. Such residues have potential as raw materials for industrial bioethanol production. There is a significant advance in the synthesis of biofuels from fruit and vegetable residues; however, most of the studies are focused on the conversion of a single type of raw material, limiting the application of the synthesis routes. This work presents a conversion methodology to produce bioethanol from carrot and broccoli residues and from their mixture; the samples of vegetable wastes has been collected in the municipality of Guanajuato, Mexico. Using the ¹H NMR technique, the characteristic signals of bioethanol are identified. On the other hand, using the UV–VIS spectrophotometry technique, a maximum of 25.63 mg of total sugar content has been determined for the mixture. Likewise, a maximum bioethanol concentration of 60.6 g/L is obtained. From a refractometry and HPLC study, a conversion to bioethanol of 34.8% is determined for the mixture of residues. This work analyses the potential of broccoli and carrot residues for bioethanol production, either as isolated or as mixed wastes.