In this study, a THC removal system was developed using an oxidation catalyst to solve the problems of the existing thermal oxidation methods, RTO and RCO. In addition, this system was applied to industrial sites to confirm the VOCs removal efficiency. As a result of testing to remove THC and VOCs by applying the reaction system for THC removal in industrial sites, the THC removal efficiency range is between 99.5% and 99.9%. The treatment efficiency of individual VOCs treated through this system was the lowest at 79.0% for methylethylketone and the highest at 91.3% for acetaldehyde, and the average treatment efficiency was about 85.4%. From these numbers, the performance was superior to the existing RTO and RCO systems that showed THC removal performance. This is due to the fact that the oxidation reaction of the oxidation catalyst is a very fast catalyst surface reaction, and the characteristics of the catalytic oxidation reaction are complete oxidation and oxidation reaction under rarefied conditions. In this study, the catalyst role in the reaction system for THC removal is to process THC simultaneously with the system heat source. This is believed to be because the reaction of the oxidation catalyst is a strongly exothermic reaction and can sufficiently provide the amount of heat necessary for the system. At the same time, an oxidation reaction that breaks the bonds of the THC component also occurs. This reaction is a strong exothermic reaction, which can help the system maintain a high temperature during the reaction, and is considered an effective system for processing high concentrations of THC in actual industrial sites where THC concentrations are high, as in this study.
This work reports the syntheses of an inexpensive and efficient asphalt-derived mesoporous carbon (AdMC) as an adsorbent. The adsorbent was activated with potassium hydroxide to increase its surface area and then characterized by SEM–EDS, FT-IR, and BET. The adsorption properties of AdMC were evaluated for the adsorptive removal of eleven Poly Aromatic Hydrocarbons (PAHs) and diesel from water samples. The prepared AdMC showed very high surface areas and high micropore volumes equal to 2316 m2/g and 1.2 cm3/g, respectively. Various experimental conditions influencing the adsorption capacity of eleven PAHs and diesel were investigated. At high concentrations, PAHs and diesel solubility in water is very low. Hence, samples were emulsified with a surfactant, and then maximum adsorption capacity was investigated. Adsorption profile of individual PAHs was examined using gas chromatography/mass spectrometry analysis followed by liquid–liquid extraction. Total hydrocarbon removal was studied using a total organic analyzer. Asphalt-derived mesoporous sorbent showed an extreme ability to remove PAHs and diesel (average adsorption capacity of 166 mg/g for individual PAHs and diesel (maximum capacity of 1600 mg/g). The experimental results fitted the Langmuir model with a correlation efficiency of 0.9853. The results obtained for both adsorbents also matched to pseudo-second-order kinetics, suggesting that the adsorption of PAHs and diesel is chemical, monolayer, and homogeneous process.
An efficient, quick and low-cost extraction and clean up method for the determination of 14 polycyclic aromatic hydrocarbons (PAHs) in the agricultural water samples was optimized using gas chromatography-tandem mass spectrometry (GC-MS/MS). The extraction of the target compounds in water sample was carried out with acetonitrile, followed by partitioning promoted by the addition of salt. As a clean-up procedure, dispersive solid phase extraction was employed to purify the analytes of interest for GC-MS/MS analysis. This method was successfully applied for the quantification of PAHs in real water samples collected for the purpose of monitoring from the waterways located in Chungbuk (15 sites) and Gyeongbuk (6 sites), S. Korea. Phenanthrene (0.54 to 2.53 μg L-1) was detected in all the water samples collected from both the sites. Fluoranthene was detected in the water samples collected from the two sites in Gyeongbuk province, but other PAHs were not determined in these water sampling sites. Based on these results, the determined PAHs were conducted using an environmental risk assessment. The risk characterization ratios (RCRs) for phenanthrene ranged from 0.37 to 3.21. These RCR values referred to as risk was not controlled because RCR values of some sites were greater than 1. In conclusion, it is proposed that the optimized method in combination with GC-MS/MS could be successfully employed for the determination of PAHs in any environmental samples including water samples.
Ochratoxin A, which is frequently detected in cereals and infant diets worldwidely, is a mycotoxin to damage mainly the kidney and liver. Because ochratoxin A is highly thermostable compound. it is necessary to study ways of reducing level of ochratoxin A by controling processing steps. However, food processes, including extrusion, expansion, roasting, and steam cooking, which are used in order to mitigate the contents of ochratoxin A, are known to produce polycyclic aromatic hydrocarbons, which are generated from radicals decomposed by pyrolysis. Therefore, this study analyzed the levels of 4 polycyclic aromatic hydrocarbons, benz (a) anthracene, chrysene, benzo (b) fluoranthene and benzo (a) pyrene in rice-based products made in high pressure and heating process. Rice samples were finely ground, and homogenized samples were alkaline treatement with 1 M KOH/EtOH and extracted with liquid-liquid extraction method using n-hexane. The extracted solution was pretreated with a silica cartridge. The purified solution was dried with nitrogen gas and dissolved in 1 mL of dichloromethane and injected into GC/MSD. We had overall recoveries for 4 polycyclic aromatic hydrocarbons spiked into rice samples ranging from 92.8 to 110.2%. The limit of quantitations of benz (a) anthracene, chrysene, benzo (b) fluoranthene and benzo (a) pyrene in rice-based product were 0.19 ng/g, 0.38 ng/g, 0.51 ng/g, and 0.31 ng/g, respectively. However, these 4 polycyclic aromatic hydrocarbons in all processed rice samples were not detected.
Honey bee swarming is a natural phenomenon that occurs by changes of colony (i.e. population size and queen condition) and environment conditions. As cuticular hydrocarbons (CHCs) are known to be involved in the communication between honey bee nest-mates, we investigated and compared the CHC profiles of worker bees from individual colonies of 9-days before swarming (PPSC), a day before swarming (PSC), swarming (SG) and remaining (non-swarming) (RG). A total of 53 CHCs were identified by GC-MS, among which 11 compounds showed significantly differential expression patterns between swarming states. Before swarming (between PPSC and PSC), detection levels of 4 CHCs were significantly different, suggesting that production of some CHCs changed prior to swarming for swarming preparation. Six CHCs were deferentially produced between PSC and RG. The differential profiles of CHCs with respect to different swarming states are currently under investigation.
The hazards associated with the polycyclic aromatic hydrocarbons (PAHs) are known to be recalcitrant by their structure, but white rot fungi are capable of degrading recalcitrant organic compounds. Phlebia brevispora KUC9045 isolated from Korea was investigated its efficiency of degradation of four PAHs, such as phenanthrene, anthracne, fluoranthene, and pyrene. And the species secreted extracellular laccase and MnP (Manganese dependent peroxidase) during degradation. P. brevispora KUC9045 demonstrated effective degradation rates of phenanthrene (66.3%), anthracene (67.4%), fluoranthene (61.6%), and pyrene (63.3%), respectively. For enhancement of degradation rates of PAHs by the species, Remazol Brilliant Blue R (RBBR) was preferentially supplemented to induce ligninolytic enzymes. The biodegradation rates of the three PAHs including phenanthrene, fluoranthene, and pyrene were improved as higher concentration of Remazol Brilliant Blue R was supplemented. However, anthracene was degraded with the highest rate among four PAHs after two weeks of the incubation without RBBR addition. According to the previous study, RBBR can be clearly decolorized by P. brevispora KUC9045. Hence, the present study demonstrates simultaneous degradation of dye and PAHs by the white rot fungus. And it is considered that the ligninolytic enzymes are closely related with the degradation. In addition, it indicated that dye waste water might be used to induce ligninolytic enzymes for effective degradation of PAHs.
Level and distribution of fourteen polycyclic aromatic hydrocarbons (PAHs) in the agricultural water samples collected in the waterways located in Gyeonggi and Gangwon, Korea were determined for monitoring and risk assessment. A simplified, fast but effective extraction and clean-up methods combined with gas chromatography tandem mass spectrometry (GC-MS/ MS) was employed to measure the concentration of the target compounds. The extraction of the analytes of interest in water sample (10 mL) was performed with acetonitrile (10 mL) and the salt. To purify the target PAHs, the clean-up procedure was employed with 2 mL tubes of dispersive solid phase extraction. The optimized method was validated with recoveries, method detection limit (MDL), accuracy and precision. Good recoveries for each PAHs at 10 and 25 μg L-1 were achieved (60 to 110%, with RSD <20%) with linearity (>0.99). MDL for all the analytes was achieved with 0.2 μg L-1. GC-MS/MS results showed that concentration of phenanthrene in the water samples from Gyeonggi (20 sites) ranged from 0.82 to 2.56 μg L-1 and from Gangwon (15 sites) ranged from 0.83 to 1.62 μg L-1. Other PAHs were not found in the water samples but the continuous monitoring for these areas were required.
In this study, the changes in collection efficiencies due to the time changes of activated carbons were ascertained, and in order to identify the magnitude of adsorption, the before-use and after-use iodine adsorption values were analyzed. In addition, as a result of examining the characteristics of continuous process and non-continuous process and as a result of investigating whether the emission standards would be maintained, the continuous process and printing facilities were seen as not being able to maintain the emission standards. Also were found, in the case of non-continuous process,–taking into consideration the special nature of the job –for 4Ø palletized charcoal, a collection efficiency near 50% was shown even after 96 hours. Also, when the inlet concentration was about 300ppm, it is thought that the emission standards would be maintained if the activated carbons are replaced within at least 96 hours in the case of 4Ø palletized charcoal and the use was deemed pointless in the case of carbon. The results of this study are expected to provide assistance in selecting replacement periods for activated carbons and in selecting absorbents at the project sites, and are expected to be of significant help in the selection of precipitators that can collect total hydrocarbons for compliance of the emission standards.
지질 함량이 많은 식품에 방사선 조사여부 판별방법으로 적용가능한 hydrocarbons법의 전처리 추출공정을 개선하고자, 추출시간을 효율화 하고 추출용매의 사용을 줄일 수 있는 마이크로웨이브 추출법을 적용하였다. 국제 교역량이 가장 높은 농산물중 대두를 대상으로 방사선 조사(4 kGy)를 하여 hydrocarbons 분석에 대한 전처리 조건을 최적화하고자 하였다. 예측된 대두의 최적 추출범위는 extraction time 1.3-3.2분, microwave power 61-133 W로 나타났고, 예측된 범위에서 임의점을 설정하여 회귀식에 대입하여 최적값을 예측하였을 때 값은 microwave power와 extraction time이 각각 97W과 2.2 분으로 확인되었다. 방사선조사 허가식품에 대해서 검지법의 분석결과의 정확성과 더불어 신속성이 요구되는 상황에서 hydrocarbons검지법 적용이 가능한 대두를 대상으로 MAE (micarowave-assisted extraction) 추출법을 적용한다면, 식품공전상의 현행 추출전처리(12-24시간)에 따른 분석시간을 줄이고 추출공정 개선이 가능할 것으로 본다.
PAHs(다환방향족탄화수소) 화합물은 연안역과 하구역에서 도시화와 산업활동 중 연소에 의하여 발생되어 주로 대기와 하천을 통하여 유입된다. 본 연구는 울산만으로 유입되는 하천과 하수처리장 배출수에서 PAHs 화합물의 분포특성을 평가하기 위해 2008년 갈수기인 6월과 풍수기인 8월에 수행되었다. 분석하기 위한 수시료는 울산만으로 유입되는 주요 8개 하천과 용연 하수처리장에서 채취하였다. 용존 PAHs 화합물의 농도범위와 평균값은 갈수기에 10.30~87.88(평균 39.39) ng/L, 풍수기에 10.30~69.57(평균 24.37) ng/L를 나타내었다. 용존 PAHs 화합물의 농도분포는 도심과 산업지역을 흐르는 궁천천에서 높은 값을 나타내었다. 용존 PAHs 화합물의 유입부하량 범위와 평균은 갈수기에 0.04~8.27(평균 2.05) g/day, 풍수기에는 0.03~4.77(평균 1.61) g/day로 산정되었다. 유입부하량은 많은 유량과 도시 활동의 영향을 크게 받는 태화강에서 가장 많은 양을 나타내었다. PAHs 화합물의 조성 형태는 고분자량 PAHs 화합물보다는 저분자량 PAHs 화합물이 대부분을 차지하는 경향을 보였다. 이러한 결과는 PAHs 화합물의 물리화학적 성질에 의한 것으로 다른 연구와 유사하게 나타났다. 본 연구에서 용존 PAHs 화합물의 농도는 다른 연구들의 결과보다 낮은 농도로 나타나 울산연안의 하천에서 PAHs 화합물의 오염정도가 심각하지 않은 것으로 나타났다.
This study was performed in the 48 selected public facilities in three metropolitan cities (Seoul, Daejeon, and Kwangjoo) and three general cities (Suncheon, Gwangyang, and Yeosu) to measure of the characteristics from May to October 2011. Air samples (PM2.5) were collected at the indoor and outdoor places for 24-hrs using the mini volume air sampler and analyzed 24 gaseous and particulate polycyclic aromatic hydrocarbons (PAHs) through the GC/MS. The recoveries of gaseous and particulate PAHs ranged between 60.7% to 127.2% and 57.7% to 132.5% respectively and its relative standard deviation (RSD) was 11.1%. This QA/QC results about the were adequate for the Korean national standards. The concentration levels of the PAHs in present study were acenaphthene 〉dibenz(a,h)anthracene 〉benzo(g,h,i)perylene 〉3-methylcholanthrene 〉 indeno[1,2,3-cd]pyrene for the particulate PAHs in the 48 selected public facilities. In the case of acenaphthene, the mean concentration showed the highest levels of 22.42 ng/㎥ and 34.57 ng/㎥ in the level of gaseous and particulate phase, respectively. The total PAHs concentration for the PC room is the highest in surveyed public facilities of this study and the smoking/non smoking ratio in the PC room was 3.45. This results indicated that smoking in the PC room is seemed to play a major source and the effective risk management strategies were needed to minimize or eliminate the public health effect for customers in the PC room.
Aliphatic cuticular hydrocarbons (CHCs) of different developmental stages of the spot clothing wax cicada, Lycorma delicatula (Hemiptera: Fulgoridae) were analyzed using GC and GC-MS. The numbers of carbons in the major CHCs of each developmental stage 32, 33, 28, 38, 37 in the egg, 1st, 2nd, 3rd, and 4th ins tar nymphal stages, and adults, respectively. The cuticle of Lycorma delicatula contains mainly methyl-branched 9-methylheptacosane (15.11%) in the egg stage, and a high proportion of n-heptacosane in nymphal stages (15.75, 22.42, 25.04, and 23.11 % in the 1st, 2nd, 3rd and 4th instars, respectively). In contrast, male and female adults had high proportions of n-nonacosane (13.42 and 16.55%). The chemical constituents of CHCs were classified into five groups (n-alkanes, monomethylalkanes, dimethylalkanes, trimethylalkanes, olefins) and group profiles of each developmental stage were compared. Egg surface was composed mainly monomethylalkanes (45.39%), a saturated hydrocar-bon. Nymph CHCs consisted primarily of n-alkanes (37.63 to 46.12%). There was a difference between adult male and female CHCs_ However, both contained n-alkanes and monomethylalkanes. CHCs with trimethyl or double bonded structure were rare in all stages.
The aim of study was to investigate polluted amounts 16 PAHs in railroad(waste railway ties) area, factory area and land-fill area. All of the samples were analyzed by GC-MSD(SIM mode), and the recovery range, detection limit and standard deviation obtained by this experiment were 73.88 ~ 94.75%, 0.009 ~ 2.252 μg/kg and 1.861 ~ 12.373, respectively. The concentrations of total PAHs(t-PAHs) and total carcinogenic PAHs(t-PAHcarc) in soils of three area were in the range of 12.54 ~ 3274.95 μg/kg on a wet weight basis with a mean value of 499.8 μg/kg and 0 ~122.77 μg/kg with a mean value of 20.16 μg/kg, respectively. The correlation between t-PAHs and t-PAHcarc appeared very high in railroad(waste railway ties) area (R2 = 0.8301), factory area (R2 = 0.9217) except land-fill area(R2 = 0.3782), indicated that t-PAHcarc concentration increases in proportion with t-PAHs.
Cuticular hydrocarbons (CHCs) were analyzed using GC and GC-MS, and compared with developmental stages of the Lycorma delicatula. Total Carbon numbers on all developmental stages are 21-36, and composition numbers are 51. On the whole, Carbon numbers increased as passed times on developmental stages. Except for eggs, Lycorma delicatula consisted of n-heptacosane on almost all developmental stages, and followed by n-nonacosane. Eggs, however, consisted of 9-; 11-; 13- methylheptacosane. From the above results, CHCs on developmental stages of the Lycorma delicatula consisted of n-alkane with saturated hydrocarbons (36%), followed mono- (34%) or di- (21%) methylalkanes. Above this, CHCs consisted of tri- methylalkanes (3.9%) and olefines (2.3%) that have double bond. The major constituents of CHCs on the developmental stages of Lycorma delicatula is differently proportioned, but hardly showed the difference in their composition.
Cuticular hydrocarbons (CHCs) of the pine sawyer (Monochamus saltuarius), Japanese pine sawyer (M. alternatus) and oak longicorn beetle (Moechotypa diphysis) were analyzed by GC, GC-MS and compared. Monochamus beetles are typical vectors of pine wilt disease but Moechotypa diphysis, which belongs to the same family, is not. They possess different CHCs in carbon number: 23-25 in M. saltuarius, 25-32 in M. alternatus, and 23-29 in M. diphysis. In comparison to inter-species, these three species of adult beetles have different numbers and chains of constituents of CHCs. In comparison between male and female in intra-species, the quantities of CHCs show the difference but constituents are not. Major constituent of M. saltuarius were analyzed as n-pentacosane > n-nonacosane > n-heptacosane, those of M. alternatus were n-nonacosene > n-pentacosane > n-nonacosane, and those of M. diphysis were n-heptacosane > 13-methylheptacosane > 3-methylheptacosane. From the body surface, most saturated carbohydrates of 3 species beetles are composed of n-alkane (40.2 - 65.7%) and followed by olefines > monomethylalkanes that one or two double bonds in M. saltuarius and M. alternatus. Otherwise, M. diphysis have the difference in order of monomethylalkanes > olefins.
Cuticular hydrocarbons (CHCs) were analyzed using GC and GC-MS, and compared with developmental stages of the bean bug, Riptortus pedestris. Carbon numbers on each developmental stages differed from 14-19 in eggs to 4th nymph, 25 in 5th nymph, and over 30 in last nymph that until adult emergence. Carbon numbers are increased to 16-17 carbons over time in newly emerged adults, 18-22 in 1 and 3 days after emergence, respectively; 23-27 in 6 days after emergence; approximately 30 in over 10 days after emergence. Carbon numbers increased as passed days after emergence. Riptortus pedestris consisted of n-nonacosane on almost all developmental stages, and followed by n-hentriacontane and 13,17-;15,19-demethyltritriacontane. Eggs, however, consisted of unknown compounds with high proportion and followed by n-heptacosane, and newly emerged adults also has a high proportion of n-heptacosane. From the above results, CHCs on developmental stages of the bean bug consist of n-alkane with saturated hydrocarbons (36-65 %), followed mono- or di- methylalkanes. However, newly emerged female and male adults mostly consisted of methyl-alkane. The major constituents of CHCs on the developmental stages of Riptortus pedestris is differently proportioned, but hardly showed the difference in their composition.