Production of bioethanol from a mixture of agricultural feedstocks: Biofuels characterization

Bioethanol production from a mixture of agricultural feedstock was carried out in a batch fermenter. To study the effect of optimal mixture ratio of fruit juices (100% dates; 70% dates + 30% grapes, 50% dates + 50% grapes, 30% dates + 70% grapes, 100% grapes) on ethanol yield (g ethanol/g sugar), different parameters have been monitored such as ethanol yield, total sugar, ammoniacal nitrogen, pH. It was found that the mixture of Mech Degla dates and grapes juices has the higher bioethanol concentration than that obtained from a single juice from one kind of fruit. Higher bioethanol production 155.5 g/L at 72 h was obtained when 30% dates juice was blended with 70% grapes juice. In such case, the higher initial sugar concentration is close to 228.34 g/L, and the pH droped from 4.5 to 3.87. The Luedeking-Piret model was used to describe the bioethanol production. A good agreement was found between simulated and experimental data. The influence of some physical properties on the addition of ethanol to lead-free gasoline has been studied. It was found that the addition of 5% of ethanol, to lead-free gasoline raises the RON to around 96.4, that can improve its octane number by 2 points.