Energy efficient biohydrogen production from a sea weed Ulva reticulate

Abstract

Marine macroalgae (Ulva reticulate) also known as seaweeds are widely available in coastal region and are considered as a potential feedstock for bioenergy production. It gains more attention towards biofuel production due to some advantages such as ease available, high productivity, and high conversion rate. Hydrogen is considered as clean fuel because during combustion water vapour is the only by product with no emission of carbon dioxide. Biohydrogen is used as main alternative fuel source for other fossil fuels and considered as sustainable energy with high energy yield. Biohydrogen production can be performed through anaerobic fermentation which mainly consists of hydrolysis and acidogenesis. Due to the intact algal cell membrane, hydrolysis process becomes slow thus seriously constrains consequent acidogenesis for hydrogen production. Thus, pretreatment is necessary step to disintegrate the algal cell and enhances the hydrogen production. Various pretreatment such as physical (microwave, thermal), chemical (acid, alkali, and surfactant), mechanical (sonication, dispersion) and biological (enzyme, bacteria) methods are being employed to disintegrate the cell wall, to hydrolyze the complex components into simple substances. Microwave irradiation is effective pretreatment method to disintegrate the algal biomass. Although, it is an effective method and has a limitation of high-power consumption. Therefore, by combining with chemicals, the energy input can be significantly reduced and algal solubilisation can be greatly enhanced simultaneously newline