No abstract

A techno-economic analysis of recombinant cellulase production from E. coli Eg-RK2 was conducted to support the fulfilling of Indonesia’s energy roadmap for ethanol production. The plant utilizes OPEFB as a primary substrate in cellulase production, with an expected lifetime of 12 years. The plant is assumed to be built in Indonesia and it will fulfill 1% of the total market demand. The effect of different pretreatment processes (alkaline, steam explosion, and sequential acid-alkaline) on the profitability parameter was also studied. A simulation using SuperPro Designer was used to calculate the mass and energy balance based on the kinetic parameters of E. coli EgRK2. A technology evaluation showed that alkaline pretreatment provides the highest yield with no known inhibitors formed. The steam explosion pretreatment offers the lowest rate of lignin and hemicellulose removal, and it is understood to form known fermentation inhibitors. The NPVs of the alkaline, steam explosion and sequential acid-alkaline pretreatments are USD 32,121,000, USD -36,841,000, and USD 384,000, respectively, which means the alkaline pretreatment is economically very feasible for the production of cellulase.

This study carried out the catalyst synthesis of calcium oxide (CaO) from chicken eggshells supported on activated carbon (C) and activated by KOH solution (CaO/C/KOH). The effects of variation of KOH concentration and the CaO:C mass ratio to catalyst performance were also investigated. The catalyst was used in the biodiesel production from off-grade palm oil. The catalyst with the highest catalytic activity was obtained at the CaO:C mass ratio of 12:6 and the KOH concentration of 25%. The transesterification that was performed under the conditions of the oil: methanol molar ratio of 1:10, the catalyst concentration of 1% -b oil, the reaction temperature of 65 °C, and reaction time of 3 hours produced a biodiesel yield of 85.74%. The catalyst characterization by using XRD, Hammet indicator, and Brunauer-Emmet-Teller (BET) showed the product was in the crystalline phase of CaO, K2CO3, K2O Ca(OH)2, and CaCO3, the base strength of H_> 12.2, and the specific surface area of 17.890 m2/g, respectively. The results showed that the KOH concentration in the catalyst activation process was directly proportional to the biodiesel yield. Several methyl esters such as methyl palmitate and methyl oleate were found in biodiesel through Gas Chromatography-Mass Spectrometry (GC-MS) analysis.