Dielectric barrier discharge based diesel exhaust treatment for THC removal through plasma catalysis

In this paper, an electrical discharge-based gas treatment technique for total hydrocarbon (THC) removal from diesel exhaust has been discussed, utilizing pellets made from wastes of different industrial sectors. This technique, referred to as plasma catalysis, involves activation of catalytic material placed inside the highly reactive non-thermal plasma environment generated in a dielectric barrier discharge (DBD) reactor. A wire-cylinder DBD reactor configuration was used for generating non-thermal plasma. The industrial wastes used in the present work were sourced from various sectors such as agriculture (bagasse, mulberry residue), mariculture (oyster shells) and aluminum industry (bauxite residue/red mud). Pellets were made from these wastes and were tested for possible catalytic activity under plasma activation. When compared to plasma-only treatment of the exhaust, the THC removal percentage obtained using the plasma catalysis approach was found to be higher, ranging between 40% (bagasse) to 50% (oyster shell) under plasma activation of the residue pellets. A discussion on the advantages of reusing such industrial wastes for plasma catalysis and the possible reaction pathways involved in THC removal have been discussed.