Overview on utilization of biodiesel by-product for biohydrogen production

Abstract

The booming of biodiesel production has led to the increase in biodiesel by-product or crude glycerol, which has been proven to be a potential raw material or feedstock to be adopted in green technologies for conversion into valuable products. Its versatility and sustainable nature make it a good candidate to replace petroleum based products. Efforts have been carried out to utilize crude glycerol into biohydrogen via glycerol fermentation. Biotransformation of crude glycerol is promising because the capital investment and operation is cheaper, and it can help in reducing waste thus making the process itself a clean process. This paper reviews on the latest development of biohydrogen production from biodiesel by-product with the main focus on glycerol fermentation. It also sheds light on the challenges, effects of operating parameters on biohydrogen yield, the microorganisms and their pathways, and the possible technologies that can be derived from this bioconversion of biodiesel waste.