The production of polyhydroxyalkanoates using volatile fatty acids derived from the acidogenic biohydrogen effluents: An overview

Biohydrogen production is regarded as the cleanest process of producing H2 due to its non-polluting features and its ability to valorize wastes. However, its industrialization remains stagnant due to the process barriers facing this technology. Research is now geared towards the beneficiation of acidogenic-derived metabolites to improve its competitiveness. The acidogenic effluents consist of chemical precursors known as volatile fatty acids (VFAs), which can serve as cheap substrates for polyhydroxyalkanoates (PHAs). PHAs are emerging as a potential replacement for petroleum-based plastics due to their environmental friendliness, biodegradability, and costeffectiveness. This overview discusses the synthesis of PHAs using acidogenic-derived VFAs as a carbon source. It examines the setpoint parameters that affect the recovery of PHAs using VFAs that are obtained from acidogenic effluents. Furthermore, the challenges that hinder the industrialization of PHAs are elucidated. The paper concludes by providing suggestions that could fast-track the development of PHAs using waste effluents.