Optimization of Hydrolysis of Acha Grain and Cassava Peels to Produce Bioethanol Using Sulfuric Acid

Peels of cassava and acha grains were converted to glucose using sulfuric acid hydrolysis. The peels of cassava were washed to remove adhering dirt and oven dried(50℃c)for 12hours and powered using motorized blender (model:CB-8231-J) to form powered cassava peels (PCP).The acha grains were also powdered to powdered acha grains (PAG). The process of hydrolysis was optimized using Taguchi method. An orthogonal array varying the parameters used for the study (Temperature acid concentration and time of hydrolysis) into low, medium and high was used. For temperature, and 100℃were used, for sulfuric acid concentration; 1M, 3M and 5M were used, while for duration of hydrolysis, 1,3and 5 hours were used. The result showed that as the concentration of sulfuric acid, there was an increase in the glucose content of the hydrolysates. Also, higher glucose content was observed as temperature of hydrolysis increased. The effect of duration of hydrolysis on glucose yield also indicated an increase in glucose yield with time. The highest gucose your of 602mg/g was observed at 1M sulfuric acid concentration during hydrolysis of PCP at 100°c. For acha grain,442mg/g of glucose was also observed with 1M sulfuric acid concentration at 100°. The result of the effects of duration of hydrolysis recorded highest glucose yield of 761mg/g and 582 mg/g for PCP and PAG at 5 hours of hydrolysis using 1m sulfuric acid at 100. The result of the optimization process, therefore indicate for higher and more efficient hydrolysis, low acid concentration of 1m, high hydrolysis temperature of 100c and longer duration of hydrolysis (5 hours)will give better glucose yield.