A Mini-Review on Hydrogen-Rich Syngas Production by Thermo-Catalytic and Bioconversion of Biomass and Its Environmental Implications

Abstract

The thermo-catalytic and biochemical conversion of biomass to hydrogen-rich syngas has been widely reported with less emphasis on the environmental implications of the processes. This mini-review presents an overview of different thermo-catalytic route of converting biomass to hydrogen-rich syngas as well as their environmental impact investigated using life cycle assessment methodology. The review revealed that most of the authors employed, biomass gasification, biomass pyrolysis, reforming and fermentative processes for the hydrogen-rich syngas production. Global warming potential was observed as the most significant environmental impact reported in the reviewed articles. The CO 2 equivalent emissions were found to varies with each of the processes and the type of feedstock used. Trends from literature shows that both thermo-catalytic and biochemical processes have competitive advantages and potential to compete favorable with the existing technology used for hydrogen production. Nevertheless, it cannot be ascertained that these technologies should be excluded from environmental burdens. This mini-review could be a quick guide to future research interest in environmental impact of hydrogen-rich syngas production by thermo-catalytic and biochemical conversion of biomass.

Catalytic Production of Renewable Hydrogen for Use in Fuel Cells: A Review Study

“…SR can be also applied to other renewable derived substrates, such as glycerol obtained as by-product of biodiesel production by transesterification of vegetable oils. For instance, the steam reforming of glycerol at 400 °C and 4.5 bar was performed over Rh/Al 2 O 3 catalyst, with maximum hydrogen yield of 2.6 mol/mol glycerol fed [57] or over transition metal catalysts at relatively higher temperature [58][59][60].…”

Dynamic model of isothermal moving bed reducer for chemical looping hydrogen production

“…Eventually in the 1930s, SMR overtook this approach as the SMR could demonstrate a higher conversion (up to 75%). But, the SMR process is expensive and inefficient from a thermodynamic perspective, along with increased production cost (up to 22%) through the addition of CCS systems can increase production costs by up to 22%, leading to high prices of H2 compared to fossil fuels [12]. Consequently, the high fuel prices drive the majority of the H2 productions towards non-renewable resources [12].…”

A critical review on emerging photocatalysts for syngas generation via CO2 reduction under aqueous media: a sustainable paradigm

“…13 Currently, the production of syngas predominantly relies on the conventional reforming of non-renewable sources, including fossil fuels such as natural gas, oil, and coal, generally at high temperatures and pressures. 13,58–60 Typical methods involved in syngas production include steam reforming, 61 partial oxidation, 62 and autothermal reforming or oxidative steam reforming. 63 For the first time ever, the syngas mixture (CO + H 2 ) was manufactured via the reaction between steam and incandescent coke at 1000 °C (eqn (1)).…”

“…Nevertheless, the different methods that are discussed here have shown progressive advancements in syngas production, although derived from non-renewable carbon sources such as fossil fuels or natural gases, which have limited reservoirs on Earth. 60,68 Moreover, excessive utilization of fossil fuels has already led to global warming across the world. Therefore, over the last few years, significant efforts have been made towards the development of clean and alternative routes for sustainable syngas or energy production and purification technology.…”