Bio-hydrogen production through dark fermentation of corn wastes / Mohamad Hidayat Haider

The objective of this study was to investigate biohydrogen production under parameters such as pH, temperature, and catalyst using corn wastes as substrate and cow dung as inoculum. The sample of inoculum and substrate was collected at corn farm near Tanjung Karang, Kuala Selangor. The collected sample was clean with tap water, air dry for 1-2 days. After drying process, the corn wastes were chopped down into smaller parts and stored at room temperature prior to experimental works. The substrate and inoculum were characterized using CHNS analysis, then optimized under parameter such as pH, temperature and substrate, and up-scale hydrogen production operating under optimized parameters. The characterization of inoculum and substrate was recorded in percentage of total solids, volatile solids, with carbon, hydrogen, and nitrogen content. During characterization, the total solid (TS) and volatile solids (VS) in cow dung were 16.93% and 74.9%, respectively. In comparison, corn waste consisted of more TS and VS, which were 98.95% and 93.09, respectively. Information such as cumulative biohydrogen production, lag-phase, hydraulic retention duration, and hydrogen production rate was achieved by optimizing and scaling up biohydrogen production. It was discovered that pH 5.5 yielded 13.8 ml/g H2 with the rate of 8.6 ml/h, while temperature 35°C yielded 11.7 ml/g H2 corn wastes with the rate production of 6.9 ml/h and addition of CoCl2 yielded 8.2 ml/g H2 corn wastes with the rate of production of 1.0 ml/H2. 5L up-scale biohydrogen digester at pH 5.5 produced 70.5 ml/g H2 with 7.6 ml/h production rate; temperature 35 °C produced 53.4 ml/g hydrogen with the production rate of 14.2 ml/h; and addition of CoCl2 17.6 ml/g H2 with 2.6 ml/h of production rate. Thus, corn wastes have great potential to be used as one of the energy sources to produce hydrogen and potential for agricultural wastes management.