Biogas production from alkaline pretreated cocoa pod husk as an alternative energy source
Cocoa beans, as the raw material of chocolate production, are one of the biggest export commodity in Indonesia. The beans are retrieved from the cocoa fruit removing the cocoa pod husk (CPH). CPH is rich in lignocellulosic and has potential to become a substrate for biogas production through anaerobic digestion (AD). Microorganism produces useful enzymes for AD reaction can be obtained from addition of inoculum, whereby cattle manure are commonly used. However, the lignin content in CPH is quite high, leads to low ability of CPH digestion. Hence, a pre-treatment is necessary to be done to enhance the biogas production. The research objectives of this study were to investigate the potential of goat manure as an inoculum and also to determine the bestrnchemical (alkaline) pre-treatment conditions to achieve optimum biogas production. Prior to alkaline pre-treatment, the CPH was mechanically pre-treated by drying and chopping. Four samples were given alkaline pre-treatment with varied concentration of NaOH (4% and 7%), temperature (27oC and 70oC), and residence time (100 minutes and 24 hours). The optimum biogas volume produced from alkaline pre-treated sample could reach as high as 1057 mL, with 187.2 mL of methane produced, from CPH soaked in 4% NaOH solution at 70oC for 100 minutes.
B03090 | (Rack Thesis) | Available |
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