Non-thermal plasma for catalyst regeneration: A review

An alternative technology to the thermal regeneration of coked catalysts is non-thermal plasma (NTP). The main advantage of plasma is that it allows activation of the molecules at low temperature and atmospheric pressure. The species formed under oxygen plasma are able to oxidize coke from various catalysts: zeolite, metal supported over oxide. In the present review catalysts regeneration are discussed with a strong focus on the effect of the nature and location of coke into the porosity of catalyst. Two families of catalysts that differ in pore size have been considered (i) zeolites possessing well-defined, nanometer sized pores (<1 nm) and (ii) metal/support with mesopores (2-50 nm) and macropores (>50 nm). Moreover, the interest of NTP assisted by temperature for the regeneration of a coked material is also shown. The review ends with some concluding remarks and outlook in the field of catalyst regeneration.