Rate Of Ozone Consumption Research Articles

Using green nanocomposite containing eggshell in the electroperoxone process in a baffled reactor to remove the emerging tetracycline pollutant

This study examined the eradication of Tetracycline hydrochloride (TCH) antibiotic, an emerging pollutant, by utilizing eggshell membrane activated carbon (EMAC) and magnetite (Fe3O4) nanocomposite in conjunction with the electroperoxone process employing the One Factor at a Time method (OFAT) in a baffled reactor. The nanocomposite was synthesized through the hydrothermal method using an autoclave, and its properties were assessed via XRD, FTIR, FESEM, EDAX Mapping, BET, and VSM analyses. The findings revealed that under optimal conditions (including a pollutant concentration of 300 mg/L, a natural pH of 6.2, an ozone consumption rate of 0.28 g/h, a nanocomposite concentration of 0.2 g/L, a flow intensity of 0.5 A, a wastewater recirculation flow rate of 8 L/h, and a 0.1 M Na2SO4 electrolyte concentration), 95.9%, 76.4%, and 53.4% of pollutants, COD, and TOC were respectively eliminated after 90 min. Additionally, the reusability of the nanocomposite was evaluated over five usage periods, during which the process efficiency decreased from 95.9% to 83.1%.In short, this study proved that EMAC/Fe3O4 nanocomposites are promising electroperoxone catalysts due to their low cost, excellent stability and reusability, environmental compatibility, and superior catalytic activity for TCH antibiotics removal.

Desulfurization of coal pyrite tailings with ozone

Mining is an important sector of the economy, and in the southern region of Brazil, coal mining stands out. This activity generates waste with a high pyritic content, which causes environmental problems such as acid mine drainage (AMD). Therefore, studies that aim to beneficiate or treat this waste are of high relevance. In this study, an alternative for desulfurizing pyritic waste using ozone was investigated. Ozone treatment of mining tailings suspension was evaluated as a new strategy for sulfur removal. Particle size analysis, sulfate content, ferrous ion concentration (and total iron), pH, Eh, conductivity, and X-ray fluorescence were performed. Furthermore, a kinetic analysis of ozone consumption was established. The behavior of sulfate and hydrogen ion concentrations indicates that sulfuric acid is the main reaction product, and conductivity suggests that ion release is continuous over the ozonation time. A reaction kinetics with ??1.2 was found for ozone depletion, which aids in predicting the dosage to be applied on a larger scale. This study represents a contribution to the search for alternatives for treating pyritic waste and contributes to the understanding of the reaction rate of ozone consumption in this type of reaction.

Электроозонная технология очистки навозных стоков: реализация математической модели

The disposal of animal waste products is especially urgent at large livestock facilities. In order to develop an effective technology of processing animal manure effluents, the authors have developed an effective method of their treatment and designed an experimental installation - a manure effluent treatment station including an electro-ozonizer. Cleaning is carried out in two stages: at the first stage, manure effluent is subjected to separation and flotation to remove large dispersed impurities, at the second stage, liquid fraction is treated with ozone. The technical result is achieved by fine atomization of manure effluents with a droplet diameter from 1.0 to 10.0 microns in the ozone-air mixture at an ozone concentration of 450 to 500 mg/m3 . Calculations based on the developed mathematical model have shown that fine atomization of manure effluents in a chamber with the ozone-air mixture increases the ozone concentration gradient and ozone mass transfer through the interface in 360 times as compared with barbotization of ozone into liquid. This makes it possible to increase significantly the rate of ozone consumption in chemical reactions, increase the efficiency factor, and reduce energy consumption for manure effluent treatment. The experiment was conducted at the pig-breeding farm of LLC “Novye Agrarnye Tekhnologii”, Beysuzhek Vtoroy, the Vyselki district, the Krasnodar region. The results of chemical, organoleptic and microbiological analyses confirm the high efficiency of the developed method and equipment for wastewater treatment of pig farms. The developed electro-ozonization technology and equipment improve the ecological situation on livestock farms by preventing the discharge of harmful emissions of ecologically toxic volatile compounds into the atmosphere.

Reduction of ozone dosage by using ozone in ultrafine bubbles to reduce sludge volume

Sludge ozonation, which promotes sludge disintegration and solubilization, is a promising technology for reducing waste sludge volume from biological wastewater treatment process. However, if this technology is to be widely adopted, reducing the energy consumption associated with ozone generation will be necessary. We used ultra-fine bubbles (UFBs) as ozone carriers to determine if their use could improve the efficiency of ozone treatment and reduce the ozone dose required. We used a spiral, liquid-type UFB generator, which can introduce UFBs directly into a sludge suspension. The death ratio of bacteria in sludge was used as an indicator of sludge reduction. The ozone requirement was reduced by UFBs. The ozone consumption required to achieve a death ratio of 80% was 15 mg-O3/g-MLSS in the sludge treated with ozone supplied by UFBs versus 25 and 45 mg-O3/g-MLSS in sludges treated with ozone supplied as a spiral, liquid-type microbubbles and by a diffuser, respectively. When mixing water ozonated with UFBs with sludge, the depth of the dead cell layer from the surface to the interior of the sludge floc was larger than that of ozonated water lacking UFBs at the same rate of ozone consumption. Ozone in UFBs kills bacteria inside the flocs. However, the fragmentation of sludge flocs by shear forces in the UFB generator made a larger contribution to the acceleration of bacterial death in sludge treated with ozone supplied by UFBs.

Patterns of the Ozone Pretreatment of Lignocellulosic Biomass for Subsequent Fermentation into Sugars

General patterns of ozone pretreatment for subsequent fermentation into sugars are found, based on samples of different types of plant biomass. It is shown that the reactivity of plant substrates pretreated with ozone is determined by the amount of consumed ozone, and the rate of ozone consumption depends on the content of water in a sample. Optimum values of moisture (~2FSP) and ozone consumption (2–3 mol O3/C9PPU lignin) are found.

Intensification of Sulfuric Acid Leaching of Copper from Sulfide Concentrates Using Ozone and Iron Ions

Studies have been conducted to establish the patterns of sulfuric acid dissolution of metal sulfides in the presence of environmentally friendly oxidizing agents, ozone and iron(III) ions; determine the parameters and modes of intensified extraction of metals into solution; reduce the consumption of oxidizing agents; and develop the least environmentally intense and most cost-effective methods for the extraction of nonferrous metals from sulfide ores, concentrates, and industrial wastes. A copper sulfide concentrate with a grain size of 0.074 mm (90%) and a copper content of 24.5% obtained by the flotation concentration of ore from the Udokan deposit and ozone with a concentration of 80–180 mg/L in a mixture with oxygen are used for the study. The concentrate is fed into a stirred reactor at a rate of 1–5 mL/s. Patterns are studied within the sulfuric acid concentration range 20–100 g/L and a Fe(III) ion concentration of 7.8–29.2 g/L at a solid phase to liquid phase ratio 1.1–1.5 at a temperature of 18–60°C. It has been established that the use of Fe(III) ions and ozone can significantly intensify the recovery of copper from sulfides in sulfuric acid solutions. The extraction of copper from sulfides increases in proportion to the 2.4-fold increase in the concentration of Fe(III) from 7.8 to 29.25 g/L. Ozone effectively oxidizes Fe(II) and regenerates the oxidizing agent, Fe(III) ions. With an increase in the temperature and iron concentration, the consumption of ozone for oxidation increases; namely, 0.22 mol of O3 is consumed per 1 mol of Fe, which is higher than a theoretical value of 0.17. An increase in the rate of the ozone-assisted extraction of copper from sulfides is achieved by increasing the temperature from 20 to 50°C (by 1.4 times), the concentration of ozone from 85 to 180 mg/L (3 times), the feed rate of the ozone–oxygen gas mixture from 1 to 5 mL/s (2.7 times at 20°C and 3.9 times at 50°C), and by the addition of Fe(III) ions by ~1.5 times at 50°C and [Fe(III)] = 10 g/L. The largest oxidizing activity in the sulfuric acid solution is provided by ozone decomposition products at a temperature of 50°C when the solubility of ozone decreases. The ozone utilization coefficient and specific ozone consumption rate for extracted copper decrease with an increase in the feed rate of the ozone–oxygen gas mixture from 1 to 5 mL/s by 1.42 times at 20°C and by 1.16 times at 50°C and increase with an increase in the temperature and concentration of Fe(III) due to the rapid decomposition of ozone and its unproductive use for the oxidation of iron.

Physicochemical patterns of ozone absorption by wood

Results from studying aspen and pine wood ozonation are presented. The effect the concentration of ozone, the reagent residence time, and the content of water in a sample of wood has on ozone consumption rate and ozone demand are analyzed. The residence time is shown to determine the degree of ozone conversion degree and the depth of substrate destruction. The main patterns of ozone absorption by wood with different moisture content are found. Ways of optimizing the ozonation of plant biomass are outlined.

Post-Treatment of Composting Leachate by Ozonation

The post-treatment of composting leachate via an ozonation process in laboratory scale was studied in batch mode. According to the experiments, the COD removal was 47% after 30 min of ozonation via 0.4 g/h ozone (equivalent to 2.8 mg O3/mg COD removed) at pH 9. In this circumstance, the removal of color and turbidity was also 86% and 89%, respectively. Increasing the ozone mass flow rate higher than 0.4 g/h had no considerable effect on the process variables. However, increasing the reaction time had a significant effect on both the removal of color and on COD of the leachate. Experimental data indicated that complete removal of color and 51% removal of COD were achieved after about 40 min of ozonation via 0.4 g/h ozone (equivalent to 3.3 mg O3/mg COD removed). The ozone consumption rate increased as the reaction progressed and reached 4.1 mg O3/mg COD removed after 60 min.

Reaction rates of ozone and terpenes adsorbed to model indoor surfaces

Reaction rates and reaction probabilities have been quantified on model indoor surfaces for the reaction of ozone with two monoterpenes (Δ(3) -carene and d-limonene). Molar surface loadings were obtained by performing breakthrough experiments in a plug-flow reactor (PFR) packed with beads of glass, polyvinylchloride or zirconium silicate. Reaction rates and probabilities were determined by equilibrating the PFR with both the terpene and the ozone and measuring the ozone consumption rate. To mimic typical indoor conditions, temperatures of 20, 25, and 30°C were used in both types of experiments along with a relative humidity ranging from 10% to 80%. The molar surface loading decreased with increased relative humidity, especially on glass, suggesting that water competed with the terpenes for adsorption sites. The ozone reactivity experiments indicate that higher surface loadings correspond with higher ozone uptake. The reaction probability for Δ(3) -carene with ozone ranged from 2.9 × 10(-6) to 3.0 × 10(-5) while reaction probabilities for d-limonene ranged from 2.8 × 10(-5) to 3.0 × 10(-4) . These surface reaction probabilities are roughly 10-100 times greater than the corresponding gas-phase values. Extrapolation of these results to typical indoor conditions suggests that surface conversion rates may be substantial relative to gas-phase rates, especially for lower volatility terpenoids. At present, it is unclear how important heterogeneous reactions will be in influencing indoor concentrations of terpenes, ozone and their reaction products. We observe that surface reaction probabilities were 10 to 100 times greater than their corresponding gas-phase values. Thus indoor surfaces do enhance effective reaction rates and adsorption of terpenes will increase ozone flux to otherwise low-reactivity surfaces. Extrapolation of these results to typical indoor conditions suggests that surface conversion rates may be substantial relative to gas-phase rates, especially for lower volatility terpenoids.

Removal of Toluene Using UV-Irradiated and Nonthermal Plasma–Driven Photocatalyst System

The removal of toluene using ultraviolet (UV)-irradiated and nonthermal plasma (NTP)-driven photocatalysts system was investigated. Results indicated that the combination of photocatalyst with NTP (NTP-driven photocatalyst) had much higher toluene removal efficiency (TRE) and better photocatalyst durability, compared with UV-irradiated photocatalysis. The TRE was proportional to ozone consumption rate in the NTP-driven photocatalyst system, in which catalytic ozonation played a vital role in toluene decomposition. Its mechanism of toluene destruction differed from that of photocatalytic oxidation. The active oxygen from catalytic ozone decomposition was the dominant active species in the NTP-driven photocatalyst system.

Ozone fumigation of stored grain; closed-loop recirculation and the rate of ozone consumption

Research using ozone gas as a fumigant has shown promise in controlling stored-grain insect pests. In addition to being toxic to insects, ozone gas is unstable and decays naturally into diatomic oxygen and must be continually replenished to maintain entomologically lethal concentrations in the grain mass. This two-part study quantifies the rate of ozone gas decay encountered in typical grain storage environments. From this, ozone generation capacity can be modeled. A pilot study was conducted in a commercial steel grain bin filled with 13.6 tonnes of hard red winter wheat. The bin was equipped with a closed-loop recirculation system to capture and reuse ozone gas that had passed through the grain. A second laboratory study was conducted on 55 kg samples of wheat and corn to determine the rate of ozone decay in different grains at different fumigation temperatures. With previously untreated grain samples, initial ozone decay is high. After a passivation period that ranged from 53.5 to 84.7 h, the decay rate reached a steady state. The half-life of ozone ranged from 122 s in grade 4 wheat with high foreign matter content, to 242 s in grade 2 wheat. Results show that the rate of ozone decay in wheat and corn was not significantly affected by temperature in the range in which fumigations are typically undertaken.

Treatment of winery wastewater by ozone-based advanced oxidation processes (O 3, O 3/UV and O 3/UV/H 2O 2) in a pilot-scale bubble column reactor and process economics

The effectiveness of different ozone-based advanced oxidation processes (O 3, O 3/UV and O 3/UV/H 2O 2) on the treatment of winery wastewater was investigated in a pilot-scale, bubble column reactor. At the natural pH of the wastewater (pH 4) the effectiveness of each AOP followed the sequence: O 3/UV/H 2O 2 > O 3/UV > O 3 > UV-C. The rate of chemical oxygen demand (COD) and total organic carbon (TOC) removal were enhanced by operation at neutral (pH 7) and at alkaline pH (pH 10). The underlying chemistry involved in each of the AOPs is discussed and correlated with the observed reactivity. The rate of ozone consumption in the reactor with the O 3/UV and O 3/UV/H 2O 2 processes was in the range of 70–95% during the experiments, suggesting an effective use of the ozone supplied to the system. In all the experiments the disappearance of the winery wastewater organic load was described by pseudo-first-order apparent reaction kinetics. The fastest rate constant (6.5 × 10 −3 min −1), at the natural pH of the wastewater, was observed with the O 3/UV/H 2O 2 process under optimised oxidant dose (COD/H 2O 2 = 2). An economic analysis of the operating costs of the AOPs processes investigated revealed the O 3/UV/H 2O 2 to be the most economical process (1.31 Euro m −3 g −1 of TOC mineralised under optimised conditions) to treat the winery wastewater.

Ozonation of Wastewater: Rate of Ozone Consumption and Hydroxyl Radical Yield

For the prediction of the elimination efficiency of micropollutants from wastewater by ozone, the ozone rate constants of the micropollutants and the kinetics of the reaction of ozone with wastewater must be known. The latter is multiphasic with k = 0.071 (mg DOC)(-1) s(-1) for the first mg/L ozone (at a DOC of 7.2 mg/L) followed by 0.011 (mg DOC)(-1) s(-1) the next 5 mg/L ozone and the k = 0.0019 (mg DOC)(-1) s(-1) for subsequent 4 mg/L ozone as determined by stopped-flow and batch-quench methods. An analysis of gel permeation and UV absorption data indicates that the wastewater DOC is largely polymeric, and at 12 mg/L the concentration of its subunits must be near 100 microM with epsilon(254 nm) approximately 3000 M(-1) cm(-1). The *OH radical yield as determined by the tertiary butanol assay is approximately 13%. From its dose dependence, it follows that new *OH-generating sites are formed during ozonation. The *OH scavenging capacity of the wastewater DOC has been determined at 3 x 10(4) (mg DOC)(-1) s(-1). The contribution of bicarbonate to the OH scavenging capacity is small in comparison, approximately 10% of DOC. Simulations indicate that at 5 mg/L ozone only the most reactive (k > 3 x 10(30 M(-1) s(-1)) micropollutants are fully eliminated but at 10 mg/L ozone the slow ozone decay starts to contribute and even the much less reactive ones (k = 300 M(-1) s(-1)) are oxidized (25% remaining).

Oxidation and ozonation of waste activated sludge

In this bench-scale study, the treatment of waste activated sludge (WAS) was evaluated using aerobic digestion and ozonation. Two, 2-L batch digesters, one aerated and the other one ozonated, were operated for 30 days in each phase of the study. The aerated digester simulated the aerobic digestion process and served as control to the ozonated digester. In Phase I, the aerated digester was supplied 810 mg O2 min− 1, whereas, the ozonated digester was supplied 0.88 mg O3 min− 1. In Phase II, the oxygenation rate to the aerobic digester was increased to 1,200 mg O2 min− 1 while the ozonation rate was reduced to 0.44 mg O3 min− 1. Ozone was more effective than air at oxidizing and reducing both total solids (TS) and volatile solids (VS) in the WAS. TS removals of 50% and 56% were observed for the ozonated digester versus TS removals of 23% and 35% for the aerated digester. VS removals of 40% and 42% were observed for the aerobic digester versus 57% and 74% for the ozonated digester. Aerobic digestion barely met the 38% reduction in VS required by the U.S. Environmental Protection Agency (EPA). The degradation rate constant (K d ) based on degradable TS for the ozonated digester varied from 0.082 to 0.11 days− 1 and from 0.067 to 0.09 days− 1 for the aerobic digester. Total chemical oxygen demand (TCOD) removal in the aerobic digester increased from 30% to 40% from Phase I to Phase II. TCOD removal increased slightly from 57% to 58% in the ozonated digester from Phase I to Phase II. Soluble chemical oxygen demand (SCOD) concentrations in the sludge supernatant increased with digestion time, especially in the ozonated digester. Approximately 0.12 to 0.22 mg SCOD was produced per mg of TS destroyed during ozonation. The specific oxygen uptake rate (SOUR) was consistently below the EPA standard of 1.5 mg O2 per hr per g TS, indicating that the sludge was well stabilized. The average quantity of oxygen required during aerobic digestion was 1.53 g O2 per g of TS destroyed. Actual ozone consumption rates were 0.57 mg O3 per mg TS destroyed and 1.09 mg O3 per mg TS destroyed for Phase II and Phase I, respectively.

Ozone interactions with human hair: Ozone uptake rates and product formation

In this study, the cumulative ozone uptake, the ozone reaction probability and product yields of volatile aldehydes and ketones were quantified for human scalp hair. Hair was chosen because ozone reacts readily with skin oils and the personal-care products that coat hair. Due to their proximity to the breathing zone, these reactions can influence personal exposure to ozone and its volatile reaction products. Hair samples were collected before and after washing and/or application of personal hair-care products. Samples were exposed to ozone for 24 h in a tubular Teflon reactor; ozone consumption rates and product emission rates were quantified. The mean values of integrated ozone uptake, initial and final follicle reaction probability values for eight washed and unwashed samples were, respectively, 5.1±4.4 μmol O 3 g −1, (13±8)×10 −5, and (1.0±1.3)×10 −5. Unwashed hair taken close to the scalp exhibited the highest integrated ozone uptake and reaction probability, indicating that scalp oils are responsible for much of the ozone reactivity. Otherwise there was no significant difference between washed and unwashed hair. Compounds (geranyl acetone, 6-methyl-5-hepten-2-one, and decanal) associated with ozone reacting with sebum were observed as secondary products more frequently from unwashed hair than for washed hair and the summed yield of aldehydes ranged from 0.00 to 0.86. Based on reaction probabilities, cumulative ozone uptake and typical sebum generation rates, ozone flux to skin and hair is anticipated to be nearly transport limited, reducing personal exposure to ozone and increasing exposure to reaction products.

Study of catalyzed ozonation for advanced treatment of pulp and paper mill effluents

Ozonation and catalytic ozonation (TOCCATA ® process) were used as tertiary treatments of wastewaters from three different pulp and paper mills. Laboratory batch experiments were conducted to assess the efficiency of each oxidation system for removal of organic matter. The investigations measured ozone consumption rate, variations in chemical oxygen demand (COD), total organic carbon (TOC), suspended solids (SS) and molecular weight distribution with contact time. For conventional ozonation, ozone consumption rate was dependent on the nature of the effluent. Organic matter elimination occurred both by oxidation and precipitation. Precipitation played a major role on TOC removal varying with the effluent, and was responsible for production of high final SS concentrations. However, the effluent type did not affect the ozone consumption rate for TOCCATA ®-catalyzed reactions. Using TOCCATA ®, it was shown that organic matter was removed through steady conversion of organic carbon to carbon dioxide. Finally the two oxidation systems were compared with respect to their impact on molecular weight distribution. A total removal of the two initial fractions of compounds (high and low molecular weights) was observed with two effluents. With the third effluent, only the initial fraction of low molecular weight compounds was removed by the two oxidizing systems. The results showed that ozonation and TOCCATA ®-catalyzed ozonation could achieve removals of COD of 36–76%. Depending on the effluent type, the amount of ozone consumed per gram of COD removed was lower for conventional or for catalytic ozonation.

Characterization of Gaseous Ozone Decomposition in Soil

Laboratory scale batch experiments were performed to investigate the decomposition characteristics of gaseous ozone in porous media. The decomposition rates of gaseous ozone in several solid media were determined, and the relationship of moisture content with sorbed ozone molecules was evaluated. Ozone decomposition in control and glass beads packed columns followed second-order reaction kinetics, while ozone consumption in a sand-packed column demonstrated first-order kinetics with a rate constant of 0.0109 min−1 and half-life of 1.0 h. The presence of typical metal oxides in the soil resulted in ozone consumption rates in the following order: hematite (Fe2O3) > silica-alumina (SiO2Al2O3) > alumina (Al2O3) > silica (SiO2). Ozone decomposition was highly dependent upon soil moisture content. Over 90% of the total ozone mass decomposed in the field soil with moisture content at less than 1 wt%, whereas as low as 5–15% of the total ozone mass degraded with moisture content at more than 2 wt%. In conclusion, ozone decomposition in soils was primarily controlled not only by soil organic matter but also by reactive metal oxides on the soil surface. These two factors were shown to be highly dependent upon soil moisture content.

Oxidation of Organic Pollutants of Water to Mineralization by Catalytic Ozonation

The oxidation of various organic compounds in aqueous solution was studied using catalytic ozonation (TOCCATA process) and conventional ozonation. The aim of the work is to assess catalytic ozonation efficiency for the mineralization of various organic compounds in order to envisage its application on real effluents. The selected organic compounds (about 30) are commonly found in industrial wastewaters. Comparative experiments were performed in batch mode at laboratory scale. Investigations were focused on ozone consumption rate, variations of total organic carbon, oxidation by-products and oxidation rate. Catalytic and conventional ozonation treatments were compared considering kinetic data, mineralization extent, and effect of organic functionalities. Catalytic ozonation system according to the TOCCATA process was able to convert organic compounds which were totally inert to ozone treatment and permitted considerably enhanced reaction rates when compounds were reactive to ozonation.

Characterization of raw water for the ozone application measuring ozone consumption rate

This study was conducted to illustrate an ideal method for characterizing natural waters for ozonation processes in drinking water treatment plants. A specific instrument designed with the flow injection analysis (FIA) technique enabled us to measure accurately the ozone decomposition rate, which was found to consist of two stages: the instantaneous ozone consumption stage and the slower ozone decay stage. The ozone consumption rate was measured at the initial and secondary stages by determining certain parameters called the instantaneous ozone demand (ID) and the pseudo first-order decay rate constant ( k c). Using the OH ·-probe, the yield of OH · per consumed ozone was also measured to determine its potential to produce OH · for the oxidation of micropollutants during the ozonation process. The ozone consumption of the ID values was significant in most natural waters, and substantial amounts of OH · were found to generate during the instantaneous ozone consumption stage. This study also investigated the effects of particulates, ozone doses, and sequential ozone injection on ozone decomposition kinetics and OH · formation yield.

Oxidation of polycyclic aromatic hydrocarbons by ozone in the presence of sand

A series of soil slurry experiments was performed to investigate the characteristics of PAHs removal by ozone in various conditions. Gaseous ozone was bottled into the aqueous phase in the presence of soil contaminated by PAHs. The effects of soil media, OH radical scavengers, ozone dosage, and humic acid were examined at the given experimental conditions. There exists a substantial difference in the removal of PAH according to the types of soil media tested. Baked sand showed the highest removal efficiency compared to the others. The descending order of removal rate was: BS > S > GB. This is considered to be due to the OH radical effect produced by catalytic reactions of ozone with the reactive site on the and. This is qualitatively proved by the experiment of scavenging OH radicals using tert-butanol. The comparison of half-lives of ozone in sand and glass bead columns further supports this hypothesis. It was found that about 22% of enhancement of phenanthrene destruction was accomplished by OH radicals produced by the catalytic ozone decomposition. The rate of ozone consumption for the phenanthrene oxidation was obtained as 1.88 mg/mgO3/min.