In-depth analysis of the effect of catalysts on plasma technologies for treatment of various wastes.

Energy security and waste management are gaining global attention. The modern world is producing a large amount of liquid and solid waste as a result of the increasing population and industrialization. A circular economy encourages the conversion of waste to energy and other value-added products. Waste processing requires a sustainable route for a healthy society and clean environment. One of the emerging solutions for waste treatment is plasma technology. It converts waste into syngas, oil, and char/slag depending on the thermal/non-thermal processes. Most of all the types of carbonaceous wastes can be treated by plasma processes. The addition of a catalyst to the plasma process is a developing field as plasma processes are energy intensive. This paper covers the detailed concept of plasma and catalysis. It comprises various types of plasma (non-thermal and thermal) and catalysts (zeolites, oxides, and salts) which have been used for waste treatment. Catalyst addition improves gas yield and hydrogen selectivity at moderate temperatures. Depending on the properties of the catalyst and type of plasma, comprehensive points are listed for the selection of the right catalyst for a plasma process. This review offers an in-depth analysis of the research in the field of waste-to-energy using plasma-catalytic processes. [Display omitted] • Sustainable approach towards waste valorization is highly imperative worldwide. • Synergistic effect of various catalysts and plasma has been reported. • Catalyst plasma technology gives up to 68% gas yield at 500 °C temperature. • This technology appears to be considerable alternative for waste conversion. • Limited information is available in literature on catalytic thermal plasma system. [ABSTRACT FROM AUTHOR]