THE EFFECT OF ADDITION OF METAL IONS ON THE PRODUCTION PROCESS OF BIOETHANOL FROM SWEET SORGUM

• Main Author: Kezia Pasolang Betram, Andini
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/83620
• Institution: Institut Teknologi Bandung

Indonesia's need for fuel sources continues to increase every year. This is evidenced by the increase in oil consumption in Indonesia in 2020, from 1,398,496 barrels per day to 1,471,498 barrels per day. This data reflects the increase in demand and changes in oil market dynamics during the period. This increase in oil demand and consumption is not directly proportional to the declining petroleum stocks every year. This problem can be slowly solved with Indonesia's abundant biodiversity and many alternatives to help support energy needs, especially fuel. One alternative type of fuel that can be developed to the maximum is bioethanol. Bioethanol can be produced from three categories of raw materials, namely sucrose materials such as sorghum and cane sugar, starchy materials such as corn and potatoes, and cellulose materials such as pineapple peel and wood. These three categories of raw materials are easy to find and grow in Indonesia. Based on the examples of plants in the three categories, it is known that sorghum (sweet sorghum) has great potential to be processed into bioethanol but has not been developed optimally. Its main advantages are its high brix content and short harvest life when compared to other crops such as corn, cassava, and sugarcane. In this study, an experiment was carried out on bioethanol production using the sorghum sugar fermentation method with the help of Saccharomyces cerevisiae. The fermentation process is carried out for 24 hours at a temperature of 30 °C, pH 5, and the initial Brix level of sorghum sugar is 25 °Brix with the addition of a variety of metal ions, namely Fe2+, Mg2+, and Zn2+ metal ions. The metal content used was 0.01 g/L, 0.025 g/L, and 0.05 g/L. The overall results showed that the Fe2+ variation (0.025 g/L content) produced the highest ethanol concentration of 31.2 g/L. The next results if analyzed by rate, the levels of 0.01 g/L, 0.025 g/L, and 0.05 g/L respectively produced the highest ethanol in Mg2+ metal (20.6 g/L), Fe2+ (31.2 g/L), and Zn2+ (18 g/L).