No description available.

Indiana University-Purdue University Indianapolis (IUPUI) / Researchers have shown links between various hydrocarbons and carbonyl compounds and diseases, such as cancer using exhaled breath analysis through gas chromatography/mass spectroscopy (GC/MS) analysis of volatile organic compounds (VOCs). Trained canines can detect these VOCs and can differentiate a patient suffering from cancer from a healthy control patient. In this project, an attempt has been made to develop highly sensitive sensors for the detection of low concentrations of aldehyde VOCs, such as nonanal, using conductive polymer composites (CPCs) and functionalized gold nanoparticles (f-GNPs). Facile methods have been used to enhance the sensitivity and cross-selectivity of the fabricated sensors towards nonanal. Interdigitated electrodes (IDEs) are fabricated through a photolithography process. Sensors of PEI/carbon black (CB) composite were developed via spin-coating of the material followed by the heat treatment process. Sensors of 1-Mercapto-(triethylene glycol) methyl ether functionalized GNPs are developed via drop-casting of nanomaterial and f-GNP/PEI sensors are fabricated by spin casting PEI film on top of f-GNPs. Fourier Transform Infrared (FTIR) analysis, X-Ray Diffraction (XRD) analysis, contact angle measurement, and Field Emission Scanning Electron Microscopy (FESEM) analysis was conducted to characterize the fabricated devices. The fabricated sensors have been tested with a low concentration of nonanal, nonanone, dodecane, and 1-octanol in dry air. Multiple sensors are fabricated to ensure sensors reproducibility. The sensors have been exposed repeatedly to the targeting VOC toxiv assess the repeatability of the sensors. PEI/CB sensor degradation was studied over a period of 36 days. The fabricated PEI/CB film could detect (1-80 ppm) of nonanal with higher selectivity, than the f-GNPs. The sensor0s sensitivity to nonanal was over fourteen times higher than 2-nonanone, 1-octanol, and dodecane. This shows the high selectivity of the fabricated sensor toward nonanal. In addition, the proposed sensor maintained its sensitivity to nonanal over time showing minimal degradation. The sensor response to nonanal at a relative humidity (RH) of 50% and 85% dropped less than 13% and 32% respectively. The Response of f-GNP sensors to nonanal (400 ppb - 15 ppm), dodecane (5 - 15 ppm), 1-octanol (5 - 15 ppm), and 2-nonanone (5 - 15 ppm) presented a sensitivity (∆R=R0) of 0.217%, 0.08%, 0.192% and 0.182% per ppm of the VOCs respectively. Despite the high sensitivity to the targeting VOCs, the fabricated sensors were damaged in an environment with relative humidity (RH) at 45%. A thin layer of PEI over the film was developed to ensure the sensor could tolerate longtime exposure to water vapor in an environment with RH up to 85% and enhance the sensor selectivity towards nonanal. The f-GNP/PEI sensors with nonanal (400 ppb- 15 ppm), dodecane (100 -200 ppm), 1-octanol (5 - 15 ppm) and 2-nonanone (5 - 15 ppm) presented sensitivity (∆R=R0) of 0.21%, 0.017%, 0.0438% and 0.0035% per ppm of the VOCs respectively. / 2021-04-24

Volatile organic compounds (VOCs) are emitted into the atmosphere from biogenic and anthropogenic sources with atmospheric lifetimes ranging from minutes to months, depending on the specific VOC compound considered. It is estimated that biogenic VOCs (BVOCs) (e.g. isoprenes, terpenes) make up 90% of the global atmospheric VOC budget. However, in highly industrialised regions, anthropogenic VOCs (e.g. benzene, toluene, ethylbenzene and xylene, combined abbreviated as BTEX) might dominate. VOCs have various reversible and irreversible effects on human health. They also have environmental impacts that range from changes in the population of terrestrial and aquatic ecosystems to the extinction of vulnerable species. VOCs are precursors for the formation of ozone (O3) during solar radiation initiated reactions in the presence of NOx. Tropospheric O3 is considered a pollutant, with negative impacts on human health, ecosystems and food security. O3 is also a short-lived greenhouse gas. Through reactions with radical species, VOCs lead to the formation of higher molecular weight organic compounds, which produce carbon monoxide (CO), peroxyacytyl nitrate (PAN) and ultimately secondary organic aerosol (SOA) particles. SOA particles impact directly on air quality and visibility, as well as directly and indirectly on the radiation balance of the earth that contributes to the regulation of climate. Notwithstanding the importance of atmospheric VOCs, limited data is available for VOCs in South Africa. In this study, a comprehensive dataset of BVOC and anthropogenic VOC species was obtained at the Welgegund measurement station in the North West Province, South Africa. Measurements were conducted from 9 February 2011 to 4 February 2012. Samples were collected on Tenax-TA and Carbopack-B adsorption tubes twice a week for two hours during day time and two hours during night time. The first 1.25m of the stainless steel sampling inlet was heated to 120ºC to remove O3 that could lead to sample degradation. Analyses of the sampled adsorption tubes were conducted by thermal desorption, cryofocusing, re-desorption, followed by gas chromatography separation and analysis with a mass selective detector (GC-MS). The results indicated that toluene was the most abundant aromatic hydrocarbon and heptane the most abundant alkane. Benzene is currently the only VOC listed as a criteria pollutant in the South African Air Quality Act with an annual average standard of 1.6ppb. The annual median benzene concentration was 0.13 ppb, while the highest daily benzene concentration measured was 8.7 ppb. No distinct seasonal cycles were identified for anthropogenic VOC species measured, i.e. aromatic hydrocarbons and alkanes. However, air mass history analysis indicated that air masses that passed over the Mpumalanga Highveld, the Vaal Triangle and the Johannesburg-Pretoria conurbation (collectively referred to as Area I) had significantly higher concentrations of these anthropogenic VOCs compared to air masses that passed over the western and eastern Bushveld Igneous Complex, and a region over which air masses typically followed an anti-cyclonic movement pattern (collectively referred to as Area II). Anthropogenic VOC levels in air masses that passed over the regional background (areas with no large point sources) had levels similar to air masses that had passed over Area II. Relatively good interspecies correlations (r > 0.8) between most of the aromatic hydrocarbons in air masses that had passed over Area I, with the exception of benzene, indicated that these species had common sources. Benzene, however, correlated well with CO, indicating that sources associated with incomplete combustion were most likely the origin of benzene in air masses that had passed over Area I. The interspecies concentration ratios for plumes passing over Area I indicated that this source region is relatively close to the Welgegund monitoring station and air masses that passed over this source region were substantially influenced by anthropogenic activities. The concentration ratios for plumes that passed over Area II and the Regional Background indicated that these were aged air masses. Furthermore, the concentration ratios of toluene, ethylbenzene and o,m,p-xylene (TEX) to the total aromatic concentration for air masses that passed over the various source regions showed a greater contribution to the total VOC concentration during periods of higher temperature, i.e. summer. This proved that the evaporation of solvents contributes significantly to VOC levels during the months with higher temperatures. The relative contribution of aromatic hydrocarbons to photochemical O3 formation in air masses that passed over the various source regions indicated the highest contribution was observed for air masses that passed over Area I, with Area II and the Regional Background in the same order of magnitude. The annual temporal variations of the measured BVOCs indicated that 2-methyl-3-buten-2-ol (MBO) and isoprene exhibited distinct seasonal patterns, i.e. higher values in summer and lower values in winter. The monoterpenes (MT) and the sesquiterpenes (SQT) did not follow distinct seasonal patterns. BVOC concentrations correlated relatively well to seasonal variations in temperature, photosynthetically active radiation (PAR), rainfall, relative humidity (RH) and CO2 flux. This proved that biogenic activity is responsible for BVOCs emitted. The most abundant MT was -pinene, while -caryophyllene was the most abundant SQT with annual median concentrations of 0.468 ppb and 0.022 ppb, respectively. Pollution roses for isoprene showed a dominance of sources from the north-west to the north-east, as well as the south-east. These directions correlated to areas where pockets of the savannah biome are located. / Thesis (MSc (Environmental Sciences))--North-West University, Potchefstroom Campus, 2013

Volatile organic compounds (VOCs) are emitted into the atmosphere from biogenic and anthropogenic sources with atmospheric lifetimes ranging from minutes to months, depending on the specific VOC compound considered. It is estimated that biogenic VOCs (BVOCs) (e.g. isoprenes, terpenes) make up 90% of the global atmospheric VOC budget. However, in highly industrialised regions, anthropogenic VOCs (e.g. benzene, toluene, ethylbenzene and xylene, combined abbreviated as BTEX) might dominate. VOCs have various reversible and irreversible effects on human health. They also have environmental impacts that range from changes in the population of terrestrial and aquatic ecosystems to the extinction of vulnerable species. VOCs are precursors for the formation of ozone (O3) during solar radiation initiated reactions in the presence of NOx. Tropospheric O3 is considered a pollutant, with negative impacts on human health, ecosystems and food security. O3 is also a short-lived greenhouse gas. Through reactions with radical species, VOCs lead to the formation of higher molecular weight organic compounds, which produce carbon monoxide (CO), peroxyacytyl nitrate (PAN) and ultimately secondary organic aerosol (SOA) particles. SOA particles impact directly on air quality and visibility, as well as directly and indirectly on the radiation balance of the earth that contributes to the regulation of climate. Notwithstanding the importance of atmospheric VOCs, limited data is available for VOCs in South Africa. In this study, a comprehensive dataset of BVOC and anthropogenic VOC species was obtained at the Welgegund measurement station in the North West Province, South Africa. Measurements were conducted from 9 February 2011 to 4 February 2012. Samples were collected on Tenax-TA and Carbopack-B adsorption tubes twice a week for two hours during day time and two hours during night time. The first 1.25m of the stainless steel sampling inlet was heated to 120ºC to remove O3 that could lead to sample degradation. Analyses of the sampled adsorption tubes were conducted by thermal desorption, cryofocusing, re-desorption, followed by gas chromatography separation and analysis with a mass selective detector (GC-MS). The results indicated that toluene was the most abundant aromatic hydrocarbon and heptane the most abundant alkane. Benzene is currently the only VOC listed as a criteria pollutant in the South African Air Quality Act with an annual average standard of 1.6ppb. The annual median benzene concentration was 0.13 ppb, while the highest daily benzene concentration measured was 8.7 ppb. No distinct seasonal cycles were identified for anthropogenic VOC species measured, i.e. aromatic hydrocarbons and alkanes. However, air mass history analysis indicated that air masses that passed over the Mpumalanga Highveld, the Vaal Triangle and the Johannesburg-Pretoria conurbation (collectively referred to as Area I) had significantly higher concentrations of these anthropogenic VOCs compared to air masses that passed over the western and eastern Bushveld Igneous Complex, and a region over which air masses typically followed an anti-cyclonic movement pattern (collectively referred to as Area II). Anthropogenic VOC levels in air masses that passed over the regional background (areas with no large point sources) had levels similar to air masses that had passed over Area II. Relatively good interspecies correlations (r > 0.8) between most of the aromatic hydrocarbons in air masses that had passed over Area I, with the exception of benzene, indicated that these species had common sources. Benzene, however, correlated well with CO, indicating that sources associated with incomplete combustion were most likely the origin of benzene in air masses that had passed over Area I. The interspecies concentration ratios for plumes passing over Area I indicated that this source region is relatively close to the Welgegund monitoring station and air masses that passed over this source region were substantially influenced by anthropogenic activities. The concentration ratios for plumes that passed over Area II and the Regional Background indicated that these were aged air masses. Furthermore, the concentration ratios of toluene, ethylbenzene and o,m,p-xylene (TEX) to the total aromatic concentration for air masses that passed over the various source regions showed a greater contribution to the total VOC concentration during periods of higher temperature, i.e. summer. This proved that the evaporation of solvents contributes significantly to VOC levels during the months with higher temperatures. The relative contribution of aromatic hydrocarbons to photochemical O3 formation in air masses that passed over the various source regions indicated the highest contribution was observed for air masses that passed over Area I, with Area II and the Regional Background in the same order of magnitude. The annual temporal variations of the measured BVOCs indicated that 2-methyl-3-buten-2-ol (MBO) and isoprene exhibited distinct seasonal patterns, i.e. higher values in summer and lower values in winter. The monoterpenes (MT) and the sesquiterpenes (SQT) did not follow distinct seasonal patterns. BVOC concentrations correlated relatively well to seasonal variations in temperature, photosynthetically active radiation (PAR), rainfall, relative humidity (RH) and CO2 flux. This proved that biogenic activity is responsible for BVOCs emitted. The most abundant MT was -pinene, while -caryophyllene was the most abundant SQT with annual median concentrations of 0.468 ppb and 0.022 ppb, respectively. Pollution roses for isoprene showed a dominance of sources from the north-west to the north-east, as well as the south-east. These directions correlated to areas where pockets of the savannah biome are located. / Thesis (MSc (Environmental Sciences))--North-West University, Potchefstroom Campus, 2013

Please read the abstract in the section 00front of this document / Dissertation (MSc)--University of Pretoria, 2010. / Chemistry / unrestricted

In this thesis, I combined field observations and lab experiments to explore the ecological significance of floral signals in a North American wildflower, Penstemon digitalis. More specifically, to determine the potential mechanisms driving selection on floral scent, I studied how scent mediates interactions with pollinators and antagonists by (1) observing spatiotemporal variation in scent emission (2), floral volatile ability to suppress microbes (3) the honest advertisement of nectar, and (4) if scent could aid pollinator learning by reinforcing visual signals. Scent sampling of flower development, flower tissues, rewards and inflorescence day/night emission, revealed a complexity in floral scent composition and emission that could reflect several ecological functions. The floral bouquet of P. digitalis was strongest when flowers opened, primarily emitted from flower nectaries and was strongest during the day when pollinators are most active, suggesting a role in plant-pollinator interactions. Because linalool was one of the few floral compounds found in nectar where microbe growth can degrade the pollinator reward, I studied its role in plant-microbe interactions. Bacteria strains isolated from floral and vegetative tissues were exposed to varying concentrations of nectar volatiles: linalool and methyl nicotinate. Linalool inhibited bacteria growth rate from all tissue origins whereas methyl nicotinate had little effect, suggesting that microbes could drive selection on linalool emission strength.    To determine the extent that linalool could honestly signal nectar availability, linalool-nectar associations were measured for inflorescences and flowers. Linalool predicted inflorescence nectar availability but not flower, exposing a limit to its honesty. Pollinator Bombus impatiens could use linalool as a foraging signal at varying concentrations, suggesting linalool could be learned and used to choose the most rewarding plants.    Measurement and comparison of signal-reward associations for both olfactory and visual signals/cues of P. digitalis displays found display size and linalool honest indicators of nectar. Lab behaviour experiments showed multiple signals correlated with reward could increase bumblebee foraging efficiency and promote learning, providing an explanation for why floral displays are complex and consist of multiple signals.    Together my results show that an integrated approach is required to understand the mechanisms driving the evolution of the floral phenotype.

Organic solvent production plants emit waste gases containing volatile organic compounds (VOCs) which are usually harmful to the environments and public healths. Plant managers are obligated to control the VOC emission to meet regulations at reasonable costs. A solvent plant located in southern Taiwan emits VOC-containing gas streams from some distillation columns and storage vessels with a total ventilation gas flow rate of 2.6-3.6 m3/min which contains VOCs with concentrations of less than 1,000 mg C/m3. Due to a concern of plant¡¦s safety, the plant managers constructed a full-scale biofilter for eliminating a part of the VOCs and the associated odors in the waste gas. This study aimed to investigate the effects of operation parameters such as EBRT (empty bed retention time) of the gas through the biofiltration media and organic loading to the media on the VOC removal efficiency. The biofilter is constructed of RC (reinforced concrete) with outer dimensions of 8.45 mL ¡Ñ 3.30 mW ¡Ñ 3.00 mH. The filter was also instrumented with inverters for control of speed of induced fans, and with thermometers, hygrometers, and wind speed meters. Fern chips with a total packing volume of 36 m3 was used as the biofiltration media. After inoculation with suitable microorganisms, the waste gas was introduced to the filter for VOC elimination. Nutrients (urea, milk, and a phosphate salt) and water were supplemented to the media on a daily basis. The investigation period is July, 2008 to May, 2010. In the period, THC (total hydrocarbon) concentrations for the influent and effluent gases to and from the reactor were daily measured. In addition, on a weekly basis, compositions of the VOCs in gas samples were detected by a gas chromatography equipped with a flame ionization dector (FID). On the same time basis, pH, COD (chemical oxygen demand), SS (suspended solids) in a sample of the trickled liquid from the media was analyzed. Media pH and moisture content were also analyzed for understanding the environmental conditions around the microorganisms for the VOC degradation. Results indicated that the media was in conditions of pH = 4.5-7.0, moisture = 11-61 % in the experimental phase. Trickled liquid had low COD and SS contents which can be easily treated by the existing wastewater unit in the plant, or be recycled to the media. Avarage THC, NMHC (nonmethane hydrocarbon), and VOCs were 71, 73, and 79%, respectively, with gas EBRTs of 4.2-6.3 min. With media pH of 4-5 and moisture contents 51-57%, over 90% of the influent VOCs coulb be eliminated. However, nearly dried media (moisture around 10%) had VOC removal efficiencies of lower than 30%. Nutrition tests indicate that the VOC removal efficiency was nearly proportional to milk supplementation rate. Removal of ethnaol and acetic could easily be removed with an efficiency of over 97% while 2-pentane was only 74%. Odor intensities of the treated gas could be controlled to <1,000 (dilutions to threshold) according to 3 test data.

This study aimed to develop a biofilter packed only with fern chips for the removal of air-borne low concentration VOCs (volatile organic compounds) emitted from various industries such as semiconductor manufacturing and electronic ones. The fern chip biofilters could avoid the shortcomings of traditional media, such as compaction, drying, and breakdown, which lead to the performance failure of the biofilters. The study contains two topics. The first is a performance test on the elimination of mixed VOCs used in semiconductor manufacturing industries in an air stream. The second is the one on the elimination of a single VOC (methyl ethyl ketone) in a waste gas drawn from a CCL (copper clad laminate) plant. Two pilot-scale biofilters consisted of two columns (0.40 mW¡Ñ0.40 mL¡Ñ0.70 mH acrylic column) arranged in series were used for the performance tests. Each of the two columns was packed with fern chips to a packing volume of around 56 L (0.40 mW¡Ñ0.40 mL¡Ñ0.35 mH). A sprinkler was set over the packed fern chips for providing them with water and nutrition solutions. Liquid leached from both layers of chips were collected in the bottom container of the column. In the first topic, tests were performed for biofiltration removal of VOCs in simulated semiconductor manufacturing emitted gases which consisted of IPA (isopropyl alcohol), acetone, HMDS (hexamethylene disilazane), PGME (propylene glycol monomethyl ether), and PGMEA (propylene glycol monomethyl ether acetate). From the results, it could be proposed that for achieving over 94% of the VOC removal, appropriate operation conditions are media moisture content = 52-68%, media pH = 7-8, influent VOC concentration = 150-450 mg/Am3, empty bed residence time (EBRT) = 0.75 min, and volumetric organic loading L to the whole media = 11.4-34.1 g/m3.h. In the second topic, performances of biofiltration for the removal of methyl ethyl ketone (MEK) in a gas stream from a copper clad laminate (CCL) manufacturing process were tested. Experimental results indicate that with L of <115 g /m3.h., EBRT = 0.5-1.28 min , media pH = 5.3-6.8, influent MEK concentration = 215-1,670 mg/Am3, MEK removal efficiencies of over 91% were obtained. Instant milk powder was essential to the good and stable performance of the biofilter for MEK removal.

Recently, restaurant employees exposing to cooking oil fume with potential lung cancer was highly concerned, indicating cooking oil fume emitted from restaurants might cause tremendous hazard to human health. This study combined photocatalytic oxidation and ozone oxidation technology to decompose VOCs from the exhaust of cooking oil fume from restaurants. Firstly, this study selected three different types of restaurants to implement air pollutant measurements in the indoor dinning room and stack emission. Indoor TVOCs continuous monitoring data showed that the highest TVOCs concentration was generally observed in the dining peak time. In this study, photocatalyst coated fiberglass filter was prepared by impregnation procedure and its characteristics was analyzed by SEM and XRD. Experimental results showed that the particle size of photocatalyst ranged from 25 to 50 nm and had high percentage of Anatase, suggesting that it had high photocatalytic reactivity. This study designed a continuous-flow reaction system combined nano-sized TiO2 photocatalysis with ozone oxidation technology to decompose VOCs from cooking oil fume. After passing through a fiberglass filter to remove oil droplets, the cooking oil fume then coated with nano-sized titanium oxide (UV/TiO2) fiberglass filter purification system, and then injected ozone into the system to decompose residual VOCs. This study further investigated the influences of operating parameters, including TVOCs initial concentration, O3 injection concentration, and reaction temperature on the decomposition efficiency of TVOCs by using the UV/TiO2/O3 technology. When the photocatalytic reaction temperature was 35~50¢J, the TVOC decomposition efficiency slightly increased with reaction temperature, however, when the reaction temperature went up to 55¢J, the TVOC decomposition efficiency increased only slightly, but did not increased linearly. Combination of photocatalysis and ozone oxidation system performance test results showed that ozone could decompose approximately 34% VOCs, and followed by the photocatalytical reaction of residual pollutants, achieving an overall decomposition efficiency of about 75%; while photocatalytic reaction can remove 64% of TVOCs and followed by O3 for the decomposition of residual pollutants, achieving an overall decomposition efficiency up to 94%. It showed that the combined UV/TiO2+O3 system could effectively remove VOCs in the cooking oil fume from the exhaust of restaurants. By using GC/MS to qualitatively analyze the speciation of TVOCs from cooking oil fume before and after UV/TiO2/O3, the results showed that the composition of VOCs had a decreasing trend. The peak area and dilution factor were applied to estimate the decomposition efficiency of different VOCs species. The decomposition efficiencies of pentane, 2-acrolein, acrolein, heptane, pentanal, hexanal, 2-hexenal, heptanal, heptenal and ethylhexenal were 56.21%, 72.88%, 51.33%, 32.23%, 59.04%, 69.22%, 73.53%, 41.37%, 92.57%, and 96.02%. Finally, a Langmuir-Hinshelwood kinetic model was applied to simulate the photocatalytic decomposition efficiency with the initial concentration of cooking oil fume. Model simulation results showed that the reaction rate increased with the initial TVOCs concentration. However, when TVOCs concentration increased gradually, the reaction rate became constant since the activated sites on the photocatalyst¡¦s surface was limited and cannot allow more VOC molecules diffuse to the activated sites for further photocatalytic reaction.

This research focuses on the performance study of a full-scale biofilter for treating a stream of vent gas with airborne VOCs generated from a chemical plant wastewater treatment facility. The biofilter consists of two parallel 20-ft standard containers in each a space of 5.98 m in length, 2.35 m in width and 0.50 m in height were filled with biofiltering media prepared by blending swine-manure compost and fern chips in a certain proportion. The vent gas contains methane, methanol, ethanol, acetone, dichloromethane, methyl ethyl ketone, ethyl acetate and toluene as major components and has an average flow rate of 1,320 m3/h (22 m3/min) and a temperature of 16-40oC. The purposes of this research were to confirm the VOC removal efficiency and to evaluate the elimination capacity for each VOC by monitoring operating parameters, including gas flow rate, system temperature, influent and effluent VOC concentrations of the biofilter. Experimental results show the system has a volumetric influent gas flow rate 1,153-1,470 m3/h which resulted in an average gas empty bed retention time (EBRT) of 0.64 min through the bed, a moisture of 25-70% and a pH of 2.4-6.9 for the media. Removal efficiencies of methane, methanol, ethanol, acetone, dichloromethane, MEK, ethyl acetate, toluene, NMHC and THC were 23.1, 79.3, 95.2, 82.9, 53.5, 63.7, 83.9, 41.2, 76.2 and 50.5%, respectively. Results also indicate that the VOC removal efficiency for each compound was not directly related to such important operating parameters of the biofilter as influent gas flow rate, media temperature, media pH, and the VOC concentration of the influent gas. However, the volumetric elimination rate (K) was approximately linearly varied with the corresponding loading (L) for the biodegradable VOCs in the influent gas. An average removal efficiency (K/L) of 24.5% was obtained with loadings of L < 70 g/m3h for methane. K/L of 91 and 54% were obtained for methanol with L = 0-7 and 15-22 g/m3h, respectively. Average K/L of 95% was obtained for both ethanol and acetone with L < 40 g/m3h. Removal efficiencies of 48 and 76% were obtained for methanol with L = 0-10 and 18-35 g/m3h, respectively. For MEK, an average removal of 89% was obtained with L = 0.5-4 g/m3h. Removal efficiencies of 84, 37, 48, 76 and 51% were obtained with L < 20, 0-0.2, 0.3-0.8 <60 and <120 g/m3h for ethyl acetate, toluene, NMHC and THC, respectively. This full-scale biofilter is effective in removing ethanol, ethyl acetate, acetone, methanol, and MEK. There is no significant removal efficiency for dichloromethane, toluene and methane. The performance can hopefully be improved by controlling the media in suitable conditions of moisture 50-60% and pH 7-8.