The Catalytic Total Oxidation of Polycyclic Aromatic Hydrocarbons

Abstract

Polycyclic Aromatic Hydrocarbons (PAHs) are a group of Volatile Organic Compounds (VOCs), which have serious health problems associated with their emission into the atmosphere. Catalytic oxidation is an effective abatement process to control PAH emissions, and the types of catalysts investigated have been reviewed. The majority of studies have used naphthalene as a model PAH, and in particular, catalysts containing palladium and platinum have demonstrated high activity for total oxidation. Catalysts based on the precious metals include those supported on high surface area supports, which have also been modified by adding further components, and metal exchanged zeolites. Metal oxide catalysts have also been employed and the most active for total oxidation are ceriabased. Studies of PAH total oxidation have largely been reported only in the last 10 years, and there still remains wide scope to develop improved catalysts and understand their catalytic mechanisms.

Ceria–Zirconia Mixed Metal Oxides Prepared via Mechanochemical Grinding of Carbonates for the Total Oxidation of Propane and Naphthalene

“…It has been reported previously that the relative concentrations of O β in copper-modified ceria catalysts correlate with its naphthalene total oxidation ability [44]. For both propane [45] and naphthalene [46], the process of catalytic total oxidation occurs via a Mars-van Krevelen mechanism, and the ease and extent of the oxygen removal from the lattice, i.e., its mobility, is key to catalyst activity [47]. These are controlled by surface oxygen species, oxygen vacancies, and other defect sites on the surface of the mixed metal oxide.…”

Total oxidation of naphthalene at low temperatures using palladium nanoparticles supported on inorganic oxide-coated cordierite honeycomb monoliths

“…Naphthalene is considered the least toxic and simplest molecule of the PAHs, and thus it is used as a model compound for this group of pollutants. In the literature, a range of different technologies have been studied to reduce PAH emissions [6][7][8][9][10][11][12][13]. 25 Among them, catalytic combustion is the most promising for the removal of PAHs from polluted air streams, due to its lower operating temperature and higher selectivity towards CO 2 [2].…”

Silica Supported Platinum Catalysts for Total Oxidation of the Polyaromatic Hydrocarbon Naphthalene: An Investigation of Metal Loading and Calcination Temperature

“…Both metal oxide and noble metal-based catalysts have been widely investigated for total oxidation of VOCs. However, more specifically the total oxidation of PAHs have not been studied so extensively, but there are a number of studies in the literature, which have investigated the total oxidation of naphthalene as a model PAH [5]. Naphthalene is recognised as a suitable model PAH as it is the major PAH produced in many combustion processes and it is easy to handle due to its relatively low toxicity.…”