Removal of volatile organic compounds by heterogeneous ozonation on microporous synthetic alumina silicate

Abstract

A hybrid process combining adsorption and ozonation was examined as an alternative treatment for odorous volatile organic compounds (VOCs). Methyl ethyl ketone (MEK) was chosen to study the influence of operating parameters. Two synthetic aluminosilicates (faujasite-Y and ZSM-5) were tested for adsorption and reactivity with ozone. The adsorption equilibrium measurement on both adsorbents showed that adsorption performance depends on temperature but is not sensitive to relative humidity, due to the hydrophobic properties of the materials. Adsorbed VOCs were oxidized at low temperature when ozonated flow was sent to the reactor. Regeneration of the fixed bed was achieved at the same time, releasing mainly CO(2) and H(2)O. Intermediates of oxidation, such as 2,3-butanedione and acetic acid, were identified, leading to incomplete mineralization. The influence of concentration and humidity are discussed. Four successive cycles were tested: after the first adsorption/ozonation cycle, the adsorption efficiency was not affected during subsequent cycles. These results show that the same sample of adsorbent can be used in the treatment process for a long time. Ozonation regeneration is a promising process for VOC removal.

Catalytic Ozonation of Toluene Using Chilean Natural Zeolite: The Key Role of Brønsted and Lewis Acid Sites

“…Synthetic zeolites have been used to eliminate low concentrations of VOCs (butan-2-one and toluene) from contaminated streams, using a combined procedure (adsorption and ozonation) as alternative treatment. Regeneration of VOC-saturated zeolites was conducted by ozonation in order to achieve a complete mineralization of adsorbed organic compounds [7,8]. The use of magnesium-exchanged zeolites (Mn-Y, Mn-MOR, and Mn-ZSM-5) has been reported in the catalytic ozonation of benzene.…”

Role of Lewis acid sites of ZSM-5 zeolite on gaseous ozone abatement

“…Synthetic zeolites appear as alternative materials for gaseous ozone removal from contaminated streams, due to their high thermal and chemical stability. They have been applied as catalysts in advanced oxidation processes in combination with ozone for the oxidation of volatile organic compounds from industrial emissions [5][6][7]. Concerning to gaseous ozone abatement over zeolites at ambient conditions, there are only few reported investigations [8][9][10][11].…”

Abatement of VOCs with Alternate Adsorption and Plasma-Assisted Regeneration: A Review

“…VOC molecules tend to adsorb most strongly in areas where the pore diameter of the adsorbent is close to the molecular diameter of the VOCs. For instance, in a silicalite ZSM-5 with narrow pores of 5.5 Å diameter, the methyl ethyl ketone (MEK) molecules with a kinetic diameter of 5.2 Å interact strongly with the channel walls, whereas this interaction is much smaller in large pores of aluminosilicates such as de-aluminated faujasite Y (Fau-Y-7.4 Å) [69]. The effect of the porosity and the surface chemistry of ACs on the adsorption capacity of low concentrated VOCs (benzene and toluene) has been investigated by Lillo-Rodenas et al [70,71].…”

“…For instance, Song et al demonstrated that the breakthrough time for the adsorption process was significantly reduced at elevated temperatures compared to room temperature indicating lower adsorption capacity [32]. Brodu et al have reported the influence of temperature on MEK adsorption capacity of two aluminosilicates (Fau-Y, ZSM-5) [69]. The quantity of adsorbed MEK on both Fau-Y and ZSM-5 decreased with increasing temperature.…”