RESUMEN
This study was based on the observation of volatile organic compounds (VOCs), conventional gaseous air pollutants, and meteorological parameters observed at the Xinxiang Municipal Party School site from June to August 2021. The ozone (O3) characteristics and sensitivity of O3 pollution days and the control strategy of its precursors were studied using an observation-based model (OBM). It was found that the meteorological conditions were characterized by high temperature, low humidity, and low pressure in O3-pollution days. The concentrations of O3 and its precursors all increased in the O3 pollution days. Oxygenated volatile organic compounds (OVOCs) and alkanes were the highest-concentration components of VOCs on O3 pollution days in Xinxiang, and OVOCs had the highest ozone formation potential (OFP) and hydroxyl (·OH) reactivity. According to the relative incremental reactivity (RIR) analysis, during the O3 pollution days in Xinxiang, O3sensitivity was in the VOCs-limited regime in June and in the transitional regime in July and August. Ozone production was more sensitive to alkenes and OVOCs. The RIR values of the precursors in June changed throughout the day, but O3 sensitivity remained the VOCs-limited regime. In July and August, O3 sensitivity was the VOCs-limited regime in the morning, transitional regime at noon, transitional and NOx-limited regime, respectively in the afternoon. By simulating different precursor-reduction scenarios, the results showed that the reduction of VOCs was always beneficial to the control of O3, whereas the reduction of NOx had little effect on the control of O3 and a risk of increasing O3.
RESUMEN
The printing industry has always been the key source of volatile organic compound(VOC) emissions in China. However, owing to the complexity of raw materials and processes, the fine emission inventory and its future emission reduction potential of VOCs from the printing industry have not been well characterized. In this study, the existing VOCs emission factors of the printing industry were improved, considering the neglected semi/intermediate VOCs(S/IVOCs). An emissions inventory of VOCs from the printing industry in the period of 2011-2020 in China was compiled. Through scenario analysis, the emission of VOCs under different scenarios in 2030 was predicted, and the emission reduction potential was analyzed. VOCs emissions from the printing industry in China increased first and then decreased in the period of 2011-2020. Compared with that in 2011, VOCs emissions increased by 29.6% in 2020, with an average annual growth rate of 3.0%. This was mainly due to the increasing consumption demand in the printing industry market and the lack of effective measures for integrated management of VOCs. The VOCs emission of the printing industry in China in 2020 was 861 Gg. Gravure printing and packaging processing were the two most important processes, accounting for 52.0% and 28.7%, respectively. Guangdong, Jiangsu, and Zhejiang were the largest contributors to VOC emissions, accounting for 44.12% of the total emissions. VOCs emissions of the printing industry in 2030 were 1187 Gg, 684 Gg, and 362 Gg for the baseline scenario, the general control scenario, and the strict control scenario, respectively. Compared to that in 2020, emissions under different control scenarios in 2030 increased by 37.9% and decreased by 20.6% and 57.9%, respectively. Gravure printing and packaging processing are still the focus of emission reduction.
RESUMEN
To determine the differences in emissions among different types of coatings, such as solvent-based, water-based, solvent-based ultra-violet(UV), water-based UV, and powder coatings, representative furniture manufacturing companies were selected for analysis. The emission concentrations and compositional characteristics of volatile organic compounds(VOCs) in different types of coatings were compared and studied. The ozone formation potential(OFP) and secondary organic aerosol formation potential(SOAFP) of the different types of coatings were also analyzed. Solvent-based coatings has higher TVOC concentrations, OFPs, and SOAFPs than water-based, solvent-based UV, water-based UV, and powder coatings. The concentrations and composition of VOCs emitted from the different types of coatings were also different. The main VOC groups of the solvent-based and solvent-based UV coatings were aromatic hydrocarbons and oxygenated volatile organic compounds(OVOCs). Specifically, the proportions of aromatic hydrocarbons are 41.91%-60.67% and 42.51%-43.00%, respectively, and the proportions of OVOCs were 24.75%-41.29% and 41.34%-43.21%, respectively. OVOCs accounted for the highest proportion of VOCs in the water-based, water-based UV, and powder coatings, at 54.02%-62.10%, 55.23%-64.81%, and 42.98%-46.45%, respectively. The major VOC compound of the solvent-based coatings was styrene(14.68%), and the main component of the water-based coatings was methylal(14.61%). The main species of VOCs from the solvent-based UV and water-based UV coatings were butyl acetate(15.36% and 20.56%, respectively). The most abundant species from the powder coatings was ethyl 3-ethoxy propionate(20.19%). Aromatic hydrocarbons were the most important contributor to the OFP of the solvent-based and solvent-based UV coatings, accounting for 79.84% and 80.32%, respectively. Aromatic hydrocarbons(51.48% and 36.71%) and OVOCs(42.30% and 41.03%) were the major contributors to the OFP of the water-based and water-based UV coatings, respectively. Aromatic hydrocarbons(43.46%), OVOCs(28.06%), and olefins(25.24%) were the main factors affecting the OFP of the powder coatings. Aromatic hydrocarbons dominate the SOAFP of solvent-based, water-based, solvent-based UV, water-based UV, and powder coatings, accounting for more than 99%.
Asunto(s)
Contaminantes Atmosféricos , Ozono , Compuestos Orgánicos Volátiles , Contaminantes Atmosféricos/análisis , China , Ambiente , Monitoreo del Ambiente , Diseño Interior y Mobiliario , Ozono/análisis , Compuestos Orgánicos Volátiles/análisisRESUMEN
A volatile organic compounds(VOCs) emission source classification and accounting system from domestic sources in China was established for the period between 2010 and 2018. Suggestions for the prevention and treatment of VOCs from domestic sources were developed and proposed. The results showed that the total VOCs emission inventory from domestic sources in China in 2018 was 2518 kt. Architectural decoration, asphalt road paving, cooking, and rural household biomass use source were the four largest contributors, accounting for 69.22% of the total emissions. Chemical household products and urban and rural coal use contributed equally, accounting for 10.43% and 9.98%, respectively, whilst car repair accounted for 7.75%. Shandong, Sichuan, Henan, Guangdong, Jiangsu, and Hebei were the six provinces that contributed the most(36.01%). During the 2010-2018 period, China's domestic VOCs emissions increased at a rate of 0.43%, and after reaching a peak in 2013, the emissions began to decline at a rate of 2.23%. The reason for the decline was that, on the one hand, the cleaner energy consumption of residents made a contribution to the gradual reduction of domestic coal and biomass consumption. On the other hand, the gradual saturation of housing construction in some areas, which led to a decrease in the annual construction of the country. It is recommended to promote the comprehensive management of architectural decoration, cooking methods, and car repair, while paying attention to the VOCs emissions from asphalt road paving. Meanwhile, continue to optimize the energy use structure of domestic sources, and promote the pollution control of civil coal and household biomass combustion in accordance with local regulations and multiple measures.
Asunto(s)
Contaminantes Atmosféricos , Ozono , Compuestos Orgánicos Volátiles , Contaminantes Atmosféricos/análisis , China , Monitoreo del Ambiente , Ozono/análisis , Compuestos Orgánicos Volátiles/análisisRESUMEN
In order to better understand the industrial volatile organic compounds(VOCs) emissions in China in recent years, an industrial VOCs emission inventory was developed from 2011 to 2019, based on the dynamic emission factors method and the comprehensive source classification system. The results showed that VOCs emissions increased first from 11122.7 kt in 2011 to 13397.9 kt in 2017, and then decreased to 13247.0 kt in 2019. The emission structure of the four source categories changed. The contribution from basic organic chemical industries, gasoline storage and transportation, manufacturing(i.e., coatings, inks, pigments, and similar products), and industrial protective coatings continued to increase. On the contrary, the contributions of oil and natural gas processing, automobile, and container manufacturing industries declined over the study period. Among the industrial emissions in China in 2019, industrial coating, printing, and basic organic chemical industries emitted large amounts of VOCs(accounting for 39.2% of the total emission), and because their contribution became increasingly prominent since 2011, these sectors will be the key emission sources in the future. With respect to the spatial distribution in 2019, East China and South China had the largest VOCs emissions. Shandong, Guangdong, Jiangsu, and Zhejiang were the four provinces that contributed the most, accounting for 40.6% of the total VOCs emissions.
Asunto(s)
Contaminantes Atmosféricos , Compuestos Orgánicos Volátiles , Contaminantes Atmosféricos/análisis , China , Monitoreo del Ambiente , Gasolina , Compuestos Orgánicos Volátiles/análisisRESUMEN
An industrial volatile organic compounds (VOCs) emission inventory was developed in China in 2018. It was based on the emission factors method, using a revised and updated source classification system and emission factors of key industrial sources. Results showed that the total industrial VOCs emission in China in 2018 reached as high as 12698 kt. Processes using products containing VOCs were the largest contributors, accounting for 59% of the total emission. The industrial coating industry, printing, the basic organic chemical industry, gasoline storage and transport, and the oil refinery industry were the five largest emitters, accounting for 54% of the total emission. Guangdong, Shandong, Zhejiang, and Jiangsu were the four largest emission contributors, contributing to 41% of the total emission. Hainan, Ningxia, Tibet, Heilongjiang, and Xinjiang showed the largest VOCs emission intensities, with more than 80 t·(100 million yuan)-1. Processes using products containing VOCs were the main emission contributors in most provinces. The uncertainty for the total industrial VOCs emission in 2018, based on a Monte Carlo simulation, was[-32%, 48%] at the 95% confidence interval.
Asunto(s)
Contaminantes Atmosféricos , Compuestos Orgánicos Volátiles , Contaminantes Atmosféricos/análisis , China , Monitoreo del Ambiente , Tibet , Compuestos Orgánicos Volátiles/análisisRESUMEN
Surface ozone (O3) has become the primary air pollutant in Guangzhou. Due to the influences of topography, meteorological conditions, and differences in precursor emissions, there are also large differences in the characteristics, formation mechanisms, and influencing factors of ozone in different areas of the same city. Based on the ground measurement data for October 2015 at four air quality monitoring stations that represent different types of regions in Guangzhou [urban area:Guangzhou Monitoring Center (GMC); upwind suburbs:Huadu Normal School (HNS); downwind suburbs:Panyu Middle School (PMS); Mountain area:Maofengshan (MFS)] and the WRF simulated meteorological data, the changing characteristics, influencing factors, and sensitivity of O3 were studied at each station. The results showed that the diurnal variation of O3 and NOx exhibit unimodal and bimodal characteristics (except for NOx at the MFS station). The peak ozone concentration appeared on Saturday at the GMC, HNS, and MFS stations, and on Thursday at the PMS station. The ozone concentration at the MFS station was the highest (98.61 µg·m-3), whereas that at the GMC station was the lowest (44.83 µg·m-3). The NOx inflection point intervals for O3 at different sites were:GMC:55-90 µg·m-3; PMS:30-60 µg·m-3; MFS:10-20 µg·m-3. The temperature inflection point intervals affecting the rate of O3 formation at different sites were:GMC:28-30â; HNS:26-28â; PMS:24-26â; however, this was not obvious at the MFS station. The relative humidity inflection point intervals were:GMC:55%-65% ; HNS and PMS:60%-70% ; MFS:80%-85%. The wind speed(WS) of the light wind type was proportional to the O3 concentration. The O3 concentration at the PMS site was the highest in the northwest wind direction, and the O3 concentration at the MFS site was the highest in the other wind directions. By analyzing the multivariate linear fitting of impact factors on the O3 concentration, the main controlling factors at each site were:GMC:WS and T; PMS and HNS:T and RH; MFS:RH and WS. The ozone sensitivity at each site was as follows:GMC and HNS had a VOCs-limited regime, MFS had a NOx-limited regime, and PMS had a transition regime.
Asunto(s)
Contaminantes Atmosféricos , Ozono , Contaminantes Atmosféricos/análisis , Ciudades , Monitoreo del Ambiente , Ozono/análisis , Estaciones del AñoRESUMEN
Presently, there are a few studies on the measurement of industrial organic solvents in China. To determine the content and species of volatile organic compounds (VOCs) in industrial organic solvents and to provide the emission factors of organic solvents, the Chinese wood and automotive coatings, which accounted for the largest proportion of production in the world, were investigated. Coating samples were obtained by sampling from companies and buying from markets, and were measured in accordance with the domestic standard testing methods for coatings. The content and composition spectrum of VOCs in the coatings were determined, and the ozone formation potential (OFP) was then calculated. The results showed that for wood coatings, the average content of the VOCs in solvent-based, water-based, and ultra-violet (UV) coatings were 37.28%, 9.88%, and 18.02%, respectively. For automotive coatings, the average content of the VOCs in water-based original equipment manufacturer (OEM) coating, solvent-based OEM coating, water-based refinishing coating, and solvent-based refinishing coating were 15.06%, 59.90%, 11.79%, and 54.50%, respectively. The content of the VOCs in different types of coatings varied substantially. The main components and OFP contributors were alcohols and ethers for water-based coatings, benzene series and esters for solvent-based coatings, and esters, alcohols, and ethers for UV coatings. The average value of the coating samples could meet the current mandatory national standards, but 12% of the solvent-based wood coating samples and 42% of the solvent-based OEM coating samples did not meet the standards. In addition, except for the benzene series of the water-based wood coatings, the contents of harmful substances in other coating samples were up to the standards.
Asunto(s)
Contaminantes Atmosféricos , Compuestos Orgánicos Volátiles , Contaminantes Atmosféricos/análisis , China , Monitoreo del Ambiente , Compuestos Orgánicos Volátiles/análisis , Madera/químicaRESUMEN
Based on the ground-level ozone concentration monitoring data in 2018, the ozone concentrations in 338 cities at the prefecture level and above were analyzed, and the TCEQ method was utilized to calculate the amount of locally generated ozone and regionally transported ozone in each city to divide the national ozone pollution control area and develop appropriate ozone pollution control measures. Correlation analysis was conducted between the amount of locally generated ozone and the daily maximum 8 h average ozone in each city to determine the main source of ozone pollution by determination coefficient (R2). The results show that 121 cities (35.8%) in China exceeded the standard in O3 concentration in 2018. The local generation of O3 in 104 cities has a great impact on the local O3 pollution, and is its main cause. In the other 234 cities, the main source of O3 pollution is regionally transported O3. Cities are classified into four categories based on their ozone concentration levels and pollution sources:cities with a nonattainment ozone situation and mainly locally generated ozone (N-L), cities with a nonattainment ozone situation and mainly regionally transported ozone (N-T), cities with a standard ozone situation and mainly locally generated ozone (S-L), and cities with a standard ozone situation and mainly regionally transported ozone (S-T). Finally, according to the proportion of four city types in each province, the whole country is divided into three types of control areas:severe, moderate, and general. N-L cities in the severe control area account for the largest proportion (20.3%) of the three types of control areas and the pollution is the highest; the proportion of the four categories of cities in the moderate control area are all medium; the general control area mainly includes S-T cities (65.4%), and the pollution is the lowest.
RESUMEN
The furniture manufacturing industry is a typical industry with high pollution, low added value, relatively outdated technology and low levels of pollution control. The process of furniture manufacturing uses a large number of paints and adhesives, which emit a great quantity of volatile organic compounds (VOCs). The furniture manufacturing industry is a key industry for the control of VOCs in China. The VOCs emission characteristics and environmental impact of the furniture manufacturing industry has been studied in this work, which could be helpful for the Chinese government when formulating VOCs pollution control policy for this industry. In this study, a typical furniture manufacturing enterprise was chosen as the object. The emission concentration level and source profile of VOCs in a typical enterprise was obtained, and an assessment of the environmental impact of furniture manufacturing was developed. The results showed that the concentration of VOCs in the workshop ranged from 9.18 to 181.58 mg·m-3, the concentration of VOCs in the stack was 30.64-155.94 mg·m-3, and the treatment efficiency was 7.43%-67.14%. The main species of VOCs in the workshop were aromatic hydrocarbons, esters, and aldehydes and ketones; the main species of VOCs in the stack are esters and aromatic hydrocarbons, followed by alkanes, and the main VOCs in the industry are sec-butyl acetate, toluene, m-xylene, methylal and ethylbenzene. The average ozone generation potential (OFP) of workshop and stack VOCs was 258.01 and 289.14 mg·m-3, respectively, and the average secondary organic aerosol generation potential (SOAFP) of workshop and stack VOCs was 148.66 and 165.31 mg·m-3, respectively. The most important contribution to the OFP and SOAFP in each emission sector is aromatic hydrocarbons. The OFP and SOAFP in the edge-sealing workshop are large and the VOCs should be controlled. The main malodorous substances at the shop boundary are sec-butyl acetate, m-xylene, butyl acetate, p-xylene, ethylbenzene, 1-ethyl-3-methylbenzene, o-xylene, and toluene; the VOCs at the factory boundary produce almost no odor pollution. Targeted enhanced control of aromatic hydrocarbons and esters should be adopted to achieve effective emission reduction of VOCs in furniture manufacturing.
RESUMEN
A database of refined raw materials and end treatment-based VOCs emission factors for typical solvent use sources was developed for the Pearl River Delta. For this, the impact of composition and the content of raw materials, production process, and comprehensive end treatment on the emission of VOCs was analyzed. The solvent use sources included printing, furniture manufacturing, and electronic component and equipment manufacturing. The results showed that the main VOCs in the raw materials used in printing were ethyl acetate, propyl acetate, isopropanol, propanol, and ethanol, which contributed 60%-80% to the total amount of VOCs. Ethyl acetate and butyl acetate were the main oxygenated VOCs (OVOCs) from the raw materials used in furniture manufacturing, contributing 45%-65% of the total. The main VOCs from the raw materials used in electronic component and equipment manufacturing were OVOCs such as alcohols, ethers and phenols, BTEX, and halohydrocarbons. The uncontrolled and controlled emission factors for VOCs from printing were 415.2 kg·t-1 and 184.3 kg·t-1, respectively. Of these, solvent-based raw materials accounted for 704.9 kg·t-1 and 200.1 kg·t-1, water-based raw materials accounted for 325.6 kg·t-1 and 230.3 kg·t-1, UV raw materials accounted for 197.0 kg·t-1 and 129.0 kg·t-1, and plant-based raw materials accounted for 89.0 kg·t-1 and 89.0 kg·t-1, respectively. The uncontrolled and controlled emission factors for VOCs from furniture manufacturing were 379.0 kg·t-1 and 290.2 kg·t-1, respectively. Of these, solvent-based raw materials accounted for 603.0 kg·t-1 and 448.5 kg·t-1, water-based raw materials accounted for 80.0 kg·t-1 and 80.0 kg·t-1, and powder raw materials accounted for 230.0 kg·t-1 and 184.0 kg·t-1, respectively. In electronic component and equipment manufacturing, the uncontrolled and controlled emission factors (unit:kg·million-1) for VOCs from AC ceramic capacitors, CC ceramic capacitors, varistors, and aluminum electrolytic capacitors were 59.7 and 40.8, 394.1 and 269.6, 282.4 and 193.2, and 1.2 and 1.0, respectively. The uncontrolled and controlled emission factors for VOCs from the manufacturing of continuous terminals, enameled wire, and printed circuit boards were 56.3 kg·t-1 and 42.8 kg·t-1, 87.2 kg·t-1 and 28.3 kg·t-1, and 26.4 kg·(100 m2)-1 and 11.6 kg·(100 m2)-1, respectively.
RESUMEN
An emission inventory of atmospheric pollutants from crop residue burning in Guangdong for the period 2008-2016 was developed, based on crop yield data. Emissions of species of volatile organic compounds(VOCs)and corresponding ozone formation potential (OFP) in 2016 were also estimated. Results showed that emissions of atmospheric pollutants from crop residue burning in 2013-2016 were lower than in 2008-2012. This was mainly due to the policy of prohibiting open burning of straw and to improvement of rural living standards, which reduced the proportion of straw burning. In 2016, emissions of SO2, NOx, NH3, CH4, EC, OC, NMVOC, CO, and PM2.5 were 2443.7, 16187.9, 6943.8, 29174.4, 3625.5, 14830.7, 65612.6, 591613.9, and 49463.0 t, respectively. Rice straw burning was the main source of pollutants, accounting for about 68.55% of total pollutant emissions. The five municipalities with highest atmospheric pollutant emissions were Zhanjiang, Maoming, Meizhou, Zhaoqing, and Shaoguan, together accounting for about 58.63% of total emissions. The top 10 VOC species for mass-based emissions consisted of ethylene, acetaldehyde, formaldehyde, benzene, ethyne, propylene, ethane, toluene, propane, and propionaldehyde, together contributing 67.91% to total emissions. The top ten OFP-based VOC species were ethylene, formaldehyde, acetaldehyde, propylene, 1-butylene, propionaldehyde, toluene, acrolein, isoprene, and crotonaldehyde, accounting for 80.83% of total OFP.
RESUMEN
China implemented the emission allowance and allocation strategy in 2016 to achieve effective control of volatile organic compounds (VOCs). An inventory of VOCs emissions for 2015 and future emissions for 2020 were developed and predicted, respectively, using emission factors and regression analysis. The results showed that anthropogenic VOCs emission in 2015 was 31117.0 kt. VOCs emission in 2020 under the business-as-usual scenario is predicted to be 41737.2 kt, an increase of 34.13% from that in 2015. Based on the Outline of the 13th Five-Year Plan, a total amount control target and pollution reduction task of about 28005.3 kt and 13731.9 kt, respectively, were proposed. Additionally, three control scenarios, i.e., implementing VOCs emission reduction strategies in all the key areas, in all the key industries, and in the key industries of the key areas, were established for the 13th Five-Year Plan using a scenario analysis method. The results showed that some differences exist between the potential mitigation of VOCs emissions and the emission reduction target for the three control scenarios, it is difficult to realize the emission allowance target. It is necessary to devote greater efforts to control VOCs. Moreover, reducing emissions of VOCs by implementing large-scale control projects is recommended. Further, regulation of VOC emissions in key areas and industries should be emphasized.
RESUMEN
Anthropogenic VOC emissions are classified into four sources:industrial, mobile, life, and agricultural. An anthropogenic VOC emission inventory in Jiangmen for 2014 was developed using both "top-down" and "bottom-up" emission factor methods, based on statistical survey data. The results showed that the total anthropogenic VOC emissions in Jiangmen were 75.09 kt. VOC emissions from the industrial, mobile, life, and agricultural sources were 41.37, 19.16, 11.07, and 3.50 kt, respectively, which contributed 55.09%, 25.51%, 14.74%, and 4.65% of the total anthropogenic VOC emissions. Motorcycle manufacturing, container manufacturing, coating, printing ink, manufacturing of paint and similar products, printing and packaging printing, plastics and rubber products, artificial leather manufacturing, leather tanning, burning of fossil fuels, manufacturing of basic chemical raw materials, electronics manufacturing, adhesives manufacturing, and furniture manufacturing are key industries in Jiangmen, each of which emit more than 1000 t of VOCs annually. The main emission sources in Pengjiang, Jianghai, and Heshan are industrial, which account for more than 50% of emissions in each of these districts, whereas the main emission sources in Enping and Taishan are agricultural. Districts and county-level cities will be able to achieve better emission reduction by using the local VOC inventory in the formulation of VOC emission reduction policies.
RESUMEN
Volatile organic compounds (VOCs) are an important source of industrial stench. This study was aimed at sampling and analyzing the stench source and its impact on the sensitive spot residential areas, concentrating on certain automobile manufacturing enterprise. The odor concentration and VOCs species of each vent stack, plant boundary, and sensitive spot in the enterprise were determined for November 15 and 17, 2016 via qualitative and quantitative analysis using the triangle odor bag method and gas pre-concentration system-gas chromatography-mass spectra. The results show that the odor concentrations of all vent stacks in the original equipment manufacturing plant and the engine plant were below the criterion level, those of the plant boundaries in the engine plant were below the limits, and those of the plant boundaries and sensitive spots in the original equipment manufacturing plant exceeded the allowed standards. A total of 54 VOCs species were identified, including aromatics, halogenated compounds, alkanes, alkene, cycloalkanes, ketones, esters, ethers, alcohols, sulfur compounds, and oxygen ring compounds. Halogenated compounds were the most abundant VOCs species, followed by aromatics. As a result, aromatics and halogenated compounds are the representative odorants in automobile making. 1,3-Butadiene and ethyl toluene were selected to be the typical odorants of sensitive spots according to mass concentration, detector odor threshold, and threshold dilution multiples of characteristic VOCs species in sensitive spots. The results show that the majority of characteristic VOCs species were from paint composition through the qualitative analysis based on paint used in coating shops. 1,3-Butadiene, which contributed the most to odor pollution, excluding the impact of other emission sources on sensitive spots, originates from spraying and drying processes of coating shops in the original equipment manufacturer. It is recommended that the enterprise should adopt environmentally friendly paints with low VOCs components or RTO purification equipment with higher processing efficiency to reduce the impact of stench on the sensitive residential areas from automobile making.
RESUMEN
A reactivity-based anthropogenic volatile organic compounds (VOCs) emission inventory in China in 2010 was developed on the basis of ozone formation potential (OFP), using the latest VOCs emission inventory, source profiles and maximum incremental reactivity (MIR) values. The results showed that the total anthropogenic OFP was 84187.61 kt in China in 2010, of which 6882.53 kt was from alkanes, 41496.92 kt from alkenes/alkynes, 32945.32 kt from aromatic hydrocarbons, 161.45 kt from halocarbons, and 2701.40 kt from oxygenated organics. The top 10 species in terms of OFP consisted of propene, ethene, m/p-xylene, toluene, 1-butene, o-xylene, 1,2,4-trimethyl benzene, 1,3-butadiene, m-ethyl toluene and ethyl benzene, contributing 63.95% to the total OFP but only 31.84% to the mass-based emission. Industrial sources accounted for the largest (49.29%) of the total OFP, followed by transportation sources (28.31%) and agricultural sources (22.40%). The key industrial sources with high reactivity were architectural decoration industry, oil refinery industry, storage and transport, machinery equipment industry, transport equipment industry and printing. Passenger cars, motorcycles and heavy duty vehicles were the major OFP sources of transportation. The two biomass burning sources were both the key OFP sources of agriculture. Shandong, Jiangsu, Guangdong, Zhejiang and Henan were the top five provinces with contributions of 39.65% of the total OFP in China. The reactivity-based emission inventory in this study would be of great significance for the formulation of reactivity-based ozone (O3) control strategies in China.
RESUMEN
NOx emission abatement catalysts V2O5 supported on various TiO2 including anatase, rutile and mixture of both were investigated with various physico-chemical measurements such as BET, NH3-TPD, NARP, XRD and so on, and the effect of TiO2 surface properties on the SCR (selective catalytic reduction) activity of V2O5/TiO2 catalysts was studied. It was found that the TiO2 surface properties had strong effect on the SCR activity of V2O5/TiO2 catalysts. The stronger acidic property resulted in the higher exposure of active sites as well as the higher SCR activity.
Asunto(s)
Contaminantes Atmosféricos/química , Óxidos de Nitrógeno/química , Titanio/química , Compuestos de Vanadio/química , Catálisis , Concentración de Iones de Hidrógeno , Propiedades de Superficie , Difracción de Rayos XRESUMEN
Perovskite-type LaMnO3 catalysts were prepared by co-precipitation, and a series of precious metal-coating LaMnO3 catalysts were obtained by impregnation. The activity of catalysts on soot was tested by temperature-programmed reaction. Catalysts were characterized by techniques such as H2-TPR, BET, XRD, SEM and FT-IR. The activity of Pd/LaMnO3 coating 0.5% (weight) Pd is the optimal, and the maximum combustion rate temperature decreases about 40 degrees C , as compared with LaMnO3. When the coating amount is more or less than 0.5%, the ignition temperature is higher than that of pure LaMnO3. The activity of Pd/LaMnO3 is the highest among 5 precious metals-loading catalysts, and the sequence is Au,Ru,Pt and Rh. TPR experiments indicate precious metal can help the transformation of Mn4+ to Mn3+, but has less influence on reduction of Mn3+ to Mn2+ of LaMnO3. The downshift of diffraction angle of XRD indicates some precious metals enter crystal lattice of LaMnO3, the crystal sizes of catalysts become larger after precious metal loading; BET and SEM results show sintering happened to catalysts after catalytic reaction. No obvious changes occur in the IR spectra of catalysts between after and before reaction, indicating catalysts have good structural stability. In conclusion, proper amount precious metal coating on LaMnO3 effectively improve the catalytic activity of LaMnO3 on soot.
Asunto(s)
Contaminantes Atmosféricos/análisis , Lantano/química , Metales/química , Hollín/química , Contaminantes Atmosféricos/química , Catálisis , Oxidación-Reducción , Emisiones de Vehículos/análisisRESUMEN
A novel TiO2/Al2O3/ceramic cordierite honeycomb (CC)-supported V2O5-MoO3-WO3 monolithic catalyst was studied for the selective reduction of NO with NH3. The effects of reaction temperature, space velocity, NH3/NO ratio and oxygen content on selective catalytic reduction (SCR) activity were evaluated. Two other V2O5-MoO3-WO3 monolithic catalysts supported on Al2O3/CC or TiO2/CC support, two types of pellet catalysts supported on TiO2/Al2O3 or Al2O3, as well as three types of pellet catalysts V2O5-MoO3-WO3-Al2O3 and V2O5-MoO3-WO3-TiO2 were tested for comparison. The experiment results showed that this catalyst had a higher catalytic activity for SCR with comparison to others. The results of characterization showed, the preparation method of this catalyst can give rise to a higher Brunauer, Emmett, Teller (BET) surface area and pore volume, which was strongly related with the highly active performance of this catalyst. At the same time, the function of the combined carrier of TiO2/Al2O3 cannot be excluded.