Green rusts (GRs), a group of layered Fe(II)-Fe(III) hydroxide salts, have been observed to be effective reductants for degrading organic and inorganic contaminants under suboxic conditions. Furthermore, the addition of a transition metal to GRs can produce high-activity modified green rusts (HMGRs) that demonstrate higher degradation rates. Methods of modifying GRs to obtain high reactivity for degradation of PCE and nitrate were developed and reduction kinetics of PCE and nitrate by HMGRs were characterized in this study. First, the most promising HMGRs were developed through screening tests. GRs modified with Pt, Cu, Ag, or Pb were found to be effective in improving degradation rates of PCE. GR-F(Pt) and GR-F(Cu) were chosen because they showed high reactivity and produced non-chlorinated by-products. Pt and Cu showed the capability of improving reduction kinetics of nitrate by GRs. GR-F(Pt) and GR-F(Cu) were selected for further study. Second, degradation of PCE by GR-F(Cu) and GR-F(Pt) was characterized using a batch reactor system. The reaction kinetics of PCE degradation by GR-F(Cu) and GR-F(Pt) was strongly dependent on pH over the range of pH 7.5-11, with the fastest rate at pH 11. Increasing concentrations of Cu(II) over the range of 0 to 5 mM resulted in improving the reduction kinetics by a factor of more than 400, although the rate at 7.5 mM of Cu(II) was unexpectedly lower than that at 5 mM. Surface saturation behavior was observed in the rates of dechlorination of PCE by GR-F(Cu). Finally, nitrate reduction by GR-F(Cu) and GR-F(Pt) was further studied to determine the effects on degradation rates of pH, Cu(II) addition, and initial nitrate concentration. A reaction model with four sequential steps was proposed to describe the process of nitrate being reduced to ammonium and GR being oxidized to magnetite. The reaction rates of nitrate reduction by GR-F(Cu) and GR-F(Pt) was highest at pH 9. The reaction rates of GR-NO3 were improved by three orders of magnitude when Cu(II) was added in the range of 0 to 2.5 mM, while reaction rate decreased at concentrations above 2.5 mM. Saturation behavior was also observed in nitrate reduction by GR-F(Cu).

Green rusts (GRs), a group of layered Fe(II)-Fe(III) hydroxide salts, have been observed to be effective reductants for degrading organic and inorganic contaminants under suboxic conditions. Furthermore, the addition of a transition metal to GRs can produce high-activity modified green rusts (HMGRs) that demonstrate higher degradation rates. Methods of modifying GRs to obtain high reactivity for degradation of PCE and nitrate were developed and reduction kinetics of PCE and nitrate by HMGRs were characterized in this study. First, the most promising HMGRs were developed through screening tests. GRs modified with Pt, Cu, Ag, or Pb were found to be effective in improving degradation rates of PCE. GR-F(Pt) and GR-F(Cu) were chosen because they showed high reactivity and produced non-chlorinated by-products. Pt and Cu showed the capability of improving reduction kinetics of nitrate by GRs. GR-F(Pt) and GR-F(Cu) were selected for further study. Second, degradation of PCE by GR-F(Cu) and GR-F(Pt) was characterized using a batch reactor system. The reaction kinetics of PCE degradation by GR-F(Cu) and GR-F(Pt) was strongly dependent on pH over the range of pH 7.5-11, with the fastest rate at pH 11. Increasing concentrations of Cu(II) over the range of 0 to 5 mM resulted in improving the reduction kinetics by a factor of more than 400, although the rate at 7.5 mM of Cu(II) was unexpectedly lower than that at 5 mM. Surface saturation behavior was observed in the rates of dechlorination of PCE by GR-F(Cu). Finally, nitrate reduction by GR-F(Cu) and GR-F(Pt) was further studied to determine the effects on degradation rates of pH, Cu(II) addition, and initial nitrate concentration. A reaction model with four sequential steps was proposed to describe the process of nitrate being reduced to ammonium and GR being oxidized to magnetite. The reaction rates of nitrate reduction by GR-F(Cu) and GR-F(Pt) was highest at pH 9. The reaction rates of GR-NO3 were improved by three orders of magnitude when Cu(II) was added in the range of 0 to 2.5 mM, while reaction rate decreased at concentrations above 2.5 mM. Saturation behavior was also observed in nitrate reduction by GR-F(Cu).

<p>Chlorinated solvents are common contaminants in soil and water. Under anaerobic conditions microbes are capable of transforming chlorinated solvents into ethylene which would result in a remediation of the contaminated area. In order to use natural attenuation as a remediation method evidence of continuous degradation is required. Furthermore, the degradation must occur at a sufficient rate and continuous monitoring of the site is needed until the demanded levels are achieved. A field study was performed on the basis of data from a dry-cleaning facility contaminated mainly by perchloroethylene. The purpose of the study was to define the existing situation regarding distribution and transformation of contaminant in order to evaluate the possibilities of using natural attenuation as a method of remediation. Degradation of perchloroethylene proceeds through successive removal of chlorine, with the formation of trichloroethylene, dichloroethylene, vinyl chloride and ethylene. There exists evidence of degradation as far as vinyl chloride on the site but whether transformation continues to ethylene is not established. The computer model Biochlor was used to simulate distribution and degradation of the contaminants. The site possesses a complex hydrogeology and the existing data are not sufficient to distinguish the effect of degradation from other factors such as spreading of contaminant between different layers of soil. Since degradation failed to be quantified, natural attenuation can not be recommended as a safe remediation method at the considered site without further investigations.</p> / <p>Klorerade lösningsmedel är vanligt förekommande föroreningar i mark och vatten. Under anaeroba förhållanden kan mikrober omvandla klorerade kolväten till eten vilket leder till rening av det förorenade området. För att kunna använda denna naturliga nedbrytning som saneringsmetod krävs bevis för att nedbrytning fortskrider i tillräcklig utsträckning för att rena området och därefter krävs kontinuerlig provtagning till dess målen för saneringen har uppnåtts. En fallstudie utfördes utifrån data från en kemtvättsfastighet förorenad av i första hand perkloreten. Syftet var att kartlägga föroreningssituationen med avseende på spridning och nedbrytning av de klorerade föreningarna för att undersöka om naturlig nedbrytning var en möjlig framtida saneringsmetod. Nedbrytning av perkloreten sker stegvis genom att klor avspjälkas, under bildande av produkterna trikloreten, dikloreten, vinylklorid och etengas. Nedbrytning av förorening har konstaterats ske på fastigheten fram till vinylklorid men huruvida nedbrytning avstannat där eller fullföljts till etengas är ej klarlagt. Datormodellen Biochlor användes för att simulera spridning och nedbrytning av utsläppet. Fältplatsen har en komplex hydrogeologi och befintliga fältdata var inte tillräckliga för att särskilja nedbrytningens effekt från faktorer såsom spridning av förorening mellan olika jordlager. Eftersom nedbrytningen inte kunde kvantifieras kan naturlig nedbrytning inte rekommenderas som säker saneringsmetod på denna fältplats utan kompletterande analyser.</p>

O objetivo principal desta pesquisa foi desenvolver um aparato e procedimento experimental para estudar a oxidação química de organoclorados por injeção de ozônio em escala de laboratório. A concepção do ensaio desenvolvido permite realizar ensaios de coluna em meio aquoso ou em meio poroso, saturado ou não saturado, com monitoramento da concentração e da pressão absoluta de ozônio na entrada e na saída da coluna, do pH, da temperatura do meio, da temperatura ambiente e controle da vazão. Nesta pesquisa foram realizados ensaios para verificar a degradação de PCE em fase dissolvida em concentração de saturação em diversos meios: água ultrapura, águas subterrâneas coletadas em um poço cacimba e em um poço tubular profundo, e soluções de bicarbonato de sódio. A investigação experimental compreendeu ensaios de saturação e decaimento de ozônio, ensaios batch e ensaios de coluna em meios com valores de pH variados. Os resultados indicaram que o ozônio em fase dissolvida atinge a saturação após aproximadamente 15 minutos de injeção, com concentrações saturadas variando entre 90 e 170 µmol/L, dependendo do meio aquoso de estudo. O decaimento biexponencial do ozônio dissolvido mostrou tempos de meia vida t1 e t2, que variaram conforme o meio de estudo, entre 4 e 26 minutos, e 14 e 193 minutos, respectivamente. O decaimento monoexponencial resultou em tempos de meia vida entre 12 e 76 minutos. Os ensaios batch em meio aquoso mostraram degradação significativa do PCE por ozônio dissolvido comparativamente à degradação em água ultrapura não ozonizada. A adição de bicarbonato de sódio diminuiu os tempos de meia vida do ozônio em água, mas não intensificou a degradação do PCE em sistema fechado (ensaios batch). Os ensaios de coluna em meio aquoso indicaram que a volatilização e o arraste são os principais mecanismos de remoção de PCE por injeção de ozônio. As concentrações de PCE em fase dissolvida observadas no início do ensaio de coluna foram quase completamente volatilizadas e recuperadas no trap, tanto nos ensaios com a injeção de oxigênio quanto nos ensaios com injeção de ozônio. As concentrações de PCE na coluna no final dos ensaios foram inferiores ou ligeiramente superiores ao valor de intervenção estabelecido pela CETESB em 2014. Os ensaios de coluna em meio sólido (microesferas de vidro e areia) indicaram que ocorre degradação do PCE, com remoção quase total na coluna, porém com menor recuperação no trap. Possivelmente, o maior tempo de residência na coluna favorece as reações do ozônio com o PCE. / The aim of this research was to develop experimental apparatus and procedure to investigate chemical oxidation of chlorinated organic compounds by ozone injection at laboratory scale, in aqueous media and in saturated or unsaturated porous media. The test allows control of ozone inlet and outlet pressures and concentrations, pH, room and column temperature, and ozone flow. In this research, tests were performed to investigate degradation of PCE dissolved at maximum solubility concentration in several media: ultrapure water, groundwater collected in a shallow well and in a deep well, and sodium bicarbonate solutions. The experimental investigation comprised ozone saturation and decay tests, batch tests, and column tests in aqueous media with several pH values. Results indicated that dissolved ozone reaches saturation after approximately 15 minutes of injection, at saturated concentrations between 90 and 170 µmol/L, depending on the aqueous medium. Second order ozone decay half lives t1 and t2 vary, respectively, between 4-26 minutes and 14-193 minutes depending on the aqueous medium. First order decay half lives varied between 12-76 minutes. Batch tests in aqueous media showed significant PCE degradation by dissolved ozone as compared to degradation in non ozonized ultrapure water. Addiction of sodium bicarbonate decreased ozone half-lives in water but did not intensify PCE degradation as observed in the results of batch tests. Column tests in aqueous media evinced that stripping and volatilization are the mains mechanisms of PCE removal by ozone injection. Initial concentrations of dissolved PCE in the column were almost completely volatilized and recovered in the trap, for ozone injection as well as for oxygen injection. Final concentrations of dissolved PCE in the column were in the order of ppb and very near the limit allowable value according to the environmental agency of the state of São Paulo. Column tests in solid media indicate that PCE degrades and is removed from the column, but not totally recovered in the trap; probably, the more extended residence time in the column enhances reactions of ozone and PCE

Volatile chlorinated solvents such as trichloroethylene (TCE), 1,2 dichloroethane (1,2 DCA), and perchloroethylene (PCE) have been identified in the indoor air of residences located near Hill Air Force Base (AFB), Utah. These vapors can originate from either volatilization of contaminates from shallow contaminated groundwater and transport into residences or from sources within the residence. The focus of the thesis was the development of a testing strategy for determining sources of TCE, 1,2 DCA, and PCE in the indoor air of residences near Hill AFB. Eight residences were selected for this study by Hill AFB based on prior detections of TCE, 1,2 DCA, and PCE in indoor air. Residents were asked to turn off the heating, ventilation, and air conditioning (HVAC) system and keep windows and doors closed for at least 3 hours prior to the sampling visit to reduce mixing of residence air. Indoor air samples were collected on Tenax© sorbent tubes from various locations within the residences to determine the location of the potential source(s). Sampling tubes were analyzed by thermal desorption gas chromatography/mass spectrometry (GC/MS). Results from a tracer experiment using sulfur hexafluoride gas confirmed the effectiveness of sampling approach. In cases where elevated levels of chlorinated solvents were found, the suspected source materials(s) were removed and the room air was re-sampled. If removal of the materials reduced or eliminated indoor air contamination, an emission chamber was used to determine contaminant emission from the materials. Sources were identified in three of the sampled residences. Sampling in two of the residences was discontinued due to scheduling problems. Sources were not located in the remaining residences. The emission of contaminants from items identified as sources in two of the residences was measured using an emission chamber developed for this project. An ornament from residence U8-8452 emitted 36.4 ng/min/cm2 of 1,2 DCA. The emission of 1,2 DCA from a wedding dress located at residence U8-8211 was below the method detection limit of 1.99 pg/min/cm2 but the emission of PCE was 18.9 ng/min/cm2 and decreased by a factor of 7 during repeated measurements.

O objetivo principal desta pesquisa foi desenvolver um aparato e procedimento experimental para estudar a oxidação química de organoclorados por injeção de ozônio em escala de laboratório. A concepção do ensaio desenvolvido permite realizar ensaios de coluna em meio aquoso ou em meio poroso, saturado ou não saturado, com monitoramento da concentração e da pressão absoluta de ozônio na entrada e na saída da coluna, do pH, da temperatura do meio, da temperatura ambiente e controle da vazão. Nesta pesquisa foram realizados ensaios para verificar a degradação de PCE em fase dissolvida em concentração de saturação em diversos meios: água ultrapura, águas subterrâneas coletadas em um poço cacimba e em um poço tubular profundo, e soluções de bicarbonato de sódio. A investigação experimental compreendeu ensaios de saturação e decaimento de ozônio, ensaios batch e ensaios de coluna em meios com valores de pH variados. Os resultados indicaram que o ozônio em fase dissolvida atinge a saturação após aproximadamente 15 minutos de injeção, com concentrações saturadas variando entre 90 e 170 µmol/L, dependendo do meio aquoso de estudo. O decaimento biexponencial do ozônio dissolvido mostrou tempos de meia vida t1 e t2, que variaram conforme o meio de estudo, entre 4 e 26 minutos, e 14 e 193 minutos, respectivamente. O decaimento monoexponencial resultou em tempos de meia vida entre 12 e 76 minutos. Os ensaios batch em meio aquoso mostraram degradação significativa do PCE por ozônio dissolvido comparativamente à degradação em água ultrapura não ozonizada. A adição de bicarbonato de sódio diminuiu os tempos de meia vida do ozônio em água, mas não intensificou a degradação do PCE em sistema fechado (ensaios batch). Os ensaios de coluna em meio aquoso indicaram que a volatilização e o arraste são os principais mecanismos de remoção de PCE por injeção de ozônio. As concentrações de PCE em fase dissolvida observadas no início do ensaio de coluna foram quase completamente volatilizadas e recuperadas no trap, tanto nos ensaios com a injeção de oxigênio quanto nos ensaios com injeção de ozônio. As concentrações de PCE na coluna no final dos ensaios foram inferiores ou ligeiramente superiores ao valor de intervenção estabelecido pela CETESB em 2014. Os ensaios de coluna em meio sólido (microesferas de vidro e areia) indicaram que ocorre degradação do PCE, com remoção quase total na coluna, porém com menor recuperação no trap. Possivelmente, o maior tempo de residência na coluna favorece as reações do ozônio com o PCE. / The aim of this research was to develop experimental apparatus and procedure to investigate chemical oxidation of chlorinated organic compounds by ozone injection at laboratory scale, in aqueous media and in saturated or unsaturated porous media. The test allows control of ozone inlet and outlet pressures and concentrations, pH, room and column temperature, and ozone flow. In this research, tests were performed to investigate degradation of PCE dissolved at maximum solubility concentration in several media: ultrapure water, groundwater collected in a shallow well and in a deep well, and sodium bicarbonate solutions. The experimental investigation comprised ozone saturation and decay tests, batch tests, and column tests in aqueous media with several pH values. Results indicated that dissolved ozone reaches saturation after approximately 15 minutes of injection, at saturated concentrations between 90 and 170 µmol/L, depending on the aqueous medium. Second order ozone decay half lives t1 and t2 vary, respectively, between 4-26 minutes and 14-193 minutes depending on the aqueous medium. First order decay half lives varied between 12-76 minutes. Batch tests in aqueous media showed significant PCE degradation by dissolved ozone as compared to degradation in non ozonized ultrapure water. Addiction of sodium bicarbonate decreased ozone half-lives in water but did not intensify PCE degradation as observed in the results of batch tests. Column tests in aqueous media evinced that stripping and volatilization are the mains mechanisms of PCE removal by ozone injection. Initial concentrations of dissolved PCE in the column were almost completely volatilized and recovered in the trap, for ozone injection as well as for oxygen injection. Final concentrations of dissolved PCE in the column were in the order of ppb and very near the limit allowable value according to the environmental agency of the state of São Paulo. Column tests in solid media indicate that PCE degrades and is removed from the column, but not totally recovered in the trap; probably, the more extended residence time in the column enhances reactions of ozone and PCE

This work focused on using a microbubble dispersion to deliver hydrogen and carbon dioxide to anaerobic consortia to stimulate their ability to reductively dehalogenate tetrachloroethylene all the way to ethene and ethane. A continuous flow system, consisting of six anaerobic soil column bioreactors, inoculated with sediments from Virginia Tech's Duck Pond, was used for this study. Two columns received microbubbles containing hydrogen and carbon dioxide, two received sodium propionate, and two were not fed a substrate. A 30 micromolar PCE solution was delivered to the consortia at 3 ml/min. Microbubbles containing a mixture of 90% hydrogen and 10% carbon dioxide were effectively produced in a closed spinning disk generator, and were acceptable for delivering the gases to the columns. After the biodegradation study was completed, the microbubbles were found to have a pH of 4.4, due to the carbon dioxide. Microbubbles amended with NaOH to 0.01 molar yielded pH neutral microbubbles with improved stability. Methane was measured in all six columns throughout the experiment, verifying that methanogens were present. Methane levels were highest in the propionate columns, showing the the methanogens there were more active. Methane levels in the microbubble columns were similar to those in the control columns. Propionate and acetate were not detected in the columns where propionate was fed, showing that proton reducers and acetoclastic methanogens were both active. Recovery of PCE and the degradation products was almost 90% in the microbubble and control columns where most of the PCE was recovered in the effluent. The predominant product in both systems was TCE, although some ethene was detected in all four columns. The control consortia produced TCE averaging about five micromolar while the microbubble columns averaged about two micromolar TCE. One of the components of the microbubbles probably caused the lowered amounts of PCE reduction. That some ethene was seen in the microbubble columns suggests different conditions can be found to stimulate the further reduction of PCE with hydrogen and carbon dioxide microbubbles. The product recovery in the propionate columns was about 64%. Over half of the injected PCE was dechlorinated to ethene and ethane. / Ph. D.

Chlorinated solvents are common contaminants in soil and water. Under anaerobic conditions microbes are capable of transforming chlorinated solvents into ethylene which would result in a remediation of the contaminated area. In order to use natural attenuation as a remediation method evidence of continuous degradation is required. Furthermore, the degradation must occur at a sufficient rate and continuous monitoring of the site is needed until the demanded levels are achieved. A field study was performed on the basis of data from a dry-cleaning facility contaminated mainly by perchloroethylene. The purpose of the study was to define the existing situation regarding distribution and transformation of contaminant in order to evaluate the possibilities of using natural attenuation as a method of remediation. Degradation of perchloroethylene proceeds through successive removal of chlorine, with the formation of trichloroethylene, dichloroethylene, vinyl chloride and ethylene. There exists evidence of degradation as far as vinyl chloride on the site but whether transformation continues to ethylene is not established. The computer model Biochlor was used to simulate distribution and degradation of the contaminants. The site possesses a complex hydrogeology and the existing data are not sufficient to distinguish the effect of degradation from other factors such as spreading of contaminant between different layers of soil. Since degradation failed to be quantified, natural attenuation can not be recommended as a safe remediation method at the considered site without further investigations. / Klorerade lösningsmedel är vanligt förekommande föroreningar i mark och vatten. Under anaeroba förhållanden kan mikrober omvandla klorerade kolväten till eten vilket leder till rening av det förorenade området. För att kunna använda denna naturliga nedbrytning som saneringsmetod krävs bevis för att nedbrytning fortskrider i tillräcklig utsträckning för att rena området och därefter krävs kontinuerlig provtagning till dess målen för saneringen har uppnåtts. En fallstudie utfördes utifrån data från en kemtvättsfastighet förorenad av i första hand perkloreten. Syftet var att kartlägga föroreningssituationen med avseende på spridning och nedbrytning av de klorerade föreningarna för att undersöka om naturlig nedbrytning var en möjlig framtida saneringsmetod. Nedbrytning av perkloreten sker stegvis genom att klor avspjälkas, under bildande av produkterna trikloreten, dikloreten, vinylklorid och etengas. Nedbrytning av förorening har konstaterats ske på fastigheten fram till vinylklorid men huruvida nedbrytning avstannat där eller fullföljts till etengas är ej klarlagt. Datormodellen Biochlor användes för att simulera spridning och nedbrytning av utsläppet. Fältplatsen har en komplex hydrogeologi och befintliga fältdata var inte tillräckliga för att särskilja nedbrytningens effekt från faktorer såsom spridning av förorening mellan olika jordlager. Eftersom nedbrytningen inte kunde kvantifieras kan naturlig nedbrytning inte rekommenderas som säker saneringsmetod på denna fältplats utan kompletterande analyser.

No description available.

Abstract The releases of chlorinated volatile organic compounds (CVOCs) are controlled by strict regulations setting high demands for the abatement systems. Low temperature catalytic oxidation is a viable technology to economically destroy these often refractory emissions. Catalysts applied in the oxidation of CVOCs should be highly active and selective but also maintain a high resistance towards deactivation. In this study, a total of 33 different γ-Al2O3 containing metallic monoliths were studied in dichloromethane (DCM) and 25 of them in perchloroethylene (PCE) oxidation. The active compounds used were Pt, Pd, Rh or V2O5 alone or as mixtures. The catalysts were divided into three different testing sets: industrial, CVOC and research catalysts. ICP-OES, physisorption, chemisorption, XRD, UV-vis DRS, isotopic oxygen exchange, IC, NH3-TPD, H2-TPR and FESEM-EDS were used to characterise the catalysts. Screening of the industrial catalysts revealed that the addition of V2O5 improved the performance of the catalyst. DCM abatement was easily affected by the addition of VOC or water, but the effect on the PCE oxidation was only minor. Based on these screening tests, a set of CVOC catalysts were developed and installed into an industrial incinerator. The comparison between the laboratory and industrial scale studies showed that DCM oxidation in an industrial incinerator could be predicted relatively well. Instead, PCE was always seen to be oxidised far better in an industrial unit indicating that the transient oxidation conditions are beneficial for the PCE oxidation. Before starting the experiments with research catalysts, the water feed was optimised to 1.5 wt.%. Besides enhancing the HCl yields, water improved the DCM and PCE conversions. In the absence of oxygen, i.e. during destructive adsorption, the presence of water was seen to have an even more pronounced effect on the HCl formation and on the catalysts’ stability. In the DCM oxidation, the addition of the active compound on the catalyst support improved the selectivity, while the enhancing effect on the DCM conversion was only small. The high acidity together with the increased reducibility was seen to lead to an active catalyst. Among the research catalysts Pt/Al2O3 was the most active in the DCM oxidation. With PCE the addition of the active compound proved to be very beneficial also for the PCE conversion. Now Pt and Pd supported on Al2O3-CeO2 were the most active. The enhanced reducibility was seen to be the key feature of the catalyst in PCE oxidation. / Tiivistelmä Klooratuille orgaanisille hiilivedyille (CVOC) on asetettu tiukat päästörajoitukset niiden haitallisten vaikutusten takia. Tästä johtuen myös puhdistusmenetelmien tulee olla tehokkaita. Katalyyttinen puhdistus on teknologia, jolla nämä usein vaikeasti käsiteltävät yhdisteet voidaan taloudellisesti tuhota. Käytettävien katalyyttien tulee olla aktiivisia ja selektiivisiä sekä hyvin kestäviä. Tässä työssä tutkittiin yhteensä 33 erilaista γ-Al2O3-pohjaista hapetuskatalyyttiä metyleenikloridin (DCM) käsittelyssä, niistä 25 testattiin myös perkloorietyleenin (PCE) hapetuksessa. Aktiivisina metalleina katalyyteissä käytettiin platinaa, palladiumia, rhodiumia ja vanadiinia yksin tai seoksina. Katalyytit jaettiin kolmeen ryhmään: teolliset-, CVOC- ja tutkimuskatalyytit. Aktiivisuuskokeiden lisäksi katalyyttejä karakterisoitiin ICP-OES-, fysiorptio-, kemisorptio-, XRD-, UV-vis DRS-, isotooppivaihto-, IC-, NH3-TPD-, H2-TPR- ja FESEM-EDS-pintatutkimusmenetelmillä. Koetulokset osoittivat, että vanadiini paransi teollisuuskatalyyttien aktiivisuutta ja selektiivisyyttä. VOC-yhdisteen tai veden lisäys paransi DCM:n hapettumista, mutta PCE:n hapettumiseen niillä ei ollut vaikutusta. Testien perusteella kehitettiin CVOC-katalyytit, jotka asennettiin teolliseen polttolaitokseen. Laboratoriossa ja teollisuudessa tehdyissä testeissä havaittiin, että DCM:n hapettuminen oli laboratoriokokeiden perusteella ennustettavissa. Sen sijaan PCE hapettui teollisuudessa aina paljon paremmin kuin laboratorio-olosuhteissa. Tämä osoittaa, että muuttuvat hapettumisolosuhteet vaikuttivat positiivisesti PCE:n hapettumiseen. Veden määrä syöttövirrassa optimoitiin 1,5&#160;%:iin ennen tutkimuskatalyyttien testausta. Selektiivisyyden lisäksi vesi paransi DCM:n ja PCE:n konversiota. Hapettomissa olosuhteissa, ts. tuhoavien adsorptiokokeiden aikana, vesi paransi reaktion selektiivisyyttä HCl:ksi ja CO2:ksi vielä entisestään. Tämän lisäksi vesi lisäsi katalyytin stabiilisuutta. DCM:n hapetuksessa aktiivisen metallin lisäys paransi selektiivisyyttä, mutta sen sijaan vaikutus DCM:n konversioon oli hyvin pieni. Tulokset osoittivat, että aktiivisella DCM:n hapetuskatalyytillä tulee olla korkea happamuus ja hyvä pelkistyvyys. Pt/Al2O3 oli testatuista tutkimuskatalyyteistä aktiivisin. PCE:n hapetuksessa aktiivisen metallin lisäys paransi selektiivisyyden lisäksi huomattavasti myös konversiota. Katalyytin lisääntyneen pelkistymiskyvyn todettiin olevan keskeisin ominaisuus PCE:n hapettumisessa. Pt/Al2O3-CeO2 ja Pd/Al2O3-CeO2 olivat tutkimuskatalyyteistä aktiivisimpia.