Non-thermal plasma as a promising route for the removal of tar from the product gas of biomass gasification – A critical review

•Various tar removal methods are summarized.•Non-thermal plasma treatments are affective for decomposing tar compounds.•Different non-thermal plasma techniques are reviewed for degrading tar. Biomass gasification has the potential to be employed as a source of renewable energy, the process produces gaseous fuel named syngas, which could be a sustainable alternative to environmentally harming, and finite, fossil fuels. However, the feasibility of commercial scale application of biomass gasifiers is hindered by the production of tars in the gasification process. Tars incur operating issues such as fouling and clogging of piping, catalyst degradation, and tar polymerisation (potentially forming soot). Most problematically, the presence of tars can render syngas unsuitable for the use in conventional combustion engines, and gas turbines; which utilise the energy from syngas. In this review, we briefly discussed the available literature about the tar reduction techniques from biomass gasification. Then, novel non thermal plasma treatments of tars are discussed in detail.