Types and variations of buffer concentrations effect on biohydrogen productivity from sago dregs with fermentation method

Abstract

Biohydrogen has energy potential because of its minimal CO2 emissions, high hydrogen combustion point (120.1 MJ/kg), high energy density (142 kJ/g), and energy conversion efficiency. Biohydrogen can be created using organic waste such as sago dregs, offering a solution for waste management and for energy production. Only 25-30 % of sago stalks are used for making sago flour, while the remaining 70-75 %, the sago dreg, is a waste product. The majority of waste is disposed of in landfills without treatment, resulting in environmental issues. However, sago dregs consist of 44 % cellulose, 14.5 % hemicellulose, and 4.9 % lignin. It can therefore be used as a raw material for the production of biohydrogen gas. The purpose of this study is to investigate the influence that different solution concentrations (0.5 M, 1 M, 1.5 M, and 2 M) of buffer variables (NaHCO3, phosphate, acetate) have on biohydrogen gas yields during the anaerobic fermentation process. The sago dregs were pre-treated initially with a 0.4 M H2SO4 solution. This study also employed glucose at a 10 g/L concentration as a substrate for comparing outcomes. Gas chromatography research revealed that studies with a 2 M NaHCO3 buffer produced 0.665 % H2 with sago dregs as the raw material, whereas a 0.5 M NaHCO3 buffer produced 1.549 % H2 with glucose as the raw material. Sago dregs can be combined with inoculum to produce biohydrogen through batch anaerobic digestion at mesophilic (30 °C) and atmospheric pressure (1 atm) with a pH of 4.8-5.5.