Predicting the rate constants of volatile organic compounds (VOCs) with ozone reaction at different temperatures

2021 ◽  
Vol 273 ◽  
pp. 116502
Author(s):  
Yawei Liu ◽  
Shiqiang Liu ◽  
Zhiwen Cheng ◽  
Yujia Tan ◽  
Xiaoping Gao ◽  
...  
Keyword(s):  
Volatile Organic Compounds ◽  
Organic Compounds ◽  
Rate Constants ◽  
Volatile Organic ◽  
Different Temperatures

scholarly journals Application of headspace for research volatile organic compounds emitted from building materials

2018 ◽  
Vol 28 ◽  
pp. 01019
Author(s):  
Beata Kultys ◽  
Karolina Waląg
Keyword(s):  
Volatile Organic Compounds ◽  
Organic Compounds ◽  
Building Materials ◽  
Heating Temperature ◽  
Mineral Wool ◽  
Chromatography Method ◽  
Temperature Range ◽  
Volatile Organic ◽  
Different Temperatures

Headspace technique and gas chromatography method with mas detector has been used for the determination of volatile organic compounds (VOC) emitted from various building and finishing materials, such as sealing foams, mounting strips, paints, varnishes, floor coverings. The tests were carried out for different temperatures (in the temperature range of 60 to 180 °C) and the time of heated vials with tested materials inside. These tests were conducted to verify the possibility of use this method of determination the VOC emission. Interpretation of chromatograms and mass spectra allowed to identify the type of compounds emitted from the tested materials and the optimum time and temperature for each type of material was determined. The increase in heating temperature of the samples resulted in increase the type and number of identified compounds: for four materials the increase was in the whole temperature range, for others it was from 90 °C. On the other hand, emission from mineral wool was low in whole temperature range. 30-minutes heating of the samples was sufficient to identify emitted compounds for most of tested materials. Applying a longer time, i.e. 24 hours, significantly increased the sensitivity of the method.

scholarly journals Comparison of in vivo derived and scaled in vitro metabolic rate constants for several volatile organic compounds (VOCs)

2020 ◽  
Vol 69 ◽  
pp. 105002
Author(s):  
Elaina M. Kenyon ◽  
Christopher Eklund ◽  
Rex A. Pegram ◽  
John C. Lipscomb
Keyword(s):  
Volatile Organic Compounds ◽  
Metabolic Rate ◽  
Organic Compounds ◽  
Rate Constants ◽  
Volatile Organic

Analysis of Volatile Organic Compounds in Disposable Food Packages at Three types of Temperature

2012 ◽  
Vol 476-478 ◽  
pp. 2625-2629
Author(s):  
Li Xie ◽  
Jiang Yu ◽  
Shuang Li ◽  
Sha Sha Diao
Keyword(s):  
Volatile Organic Compounds ◽  
Organic Compounds ◽  
Room Temperature ◽  
Heating Temperature ◽  
Food Packages ◽  
External Standard Method ◽  
Volatile Organic ◽  
Different Temperatures ◽  
Black Plastic ◽  
Method Show

Eight volatile organic compounds (VOCs) in the four disposable food packages at refrigeration temperature, room temperature and heating temperature have been analyzed by a headspace gas chromatography and mass spectrometry method. The results of external standard method show that the amount of VOCs in the four disposable packages at different temperatures are arranged in the following order: black plastic lunch box, white plastic lunch box, paper cup, paper bowl. Under the three types of temperature for an hour, the amount of VOCs in the black plastic lunch box at heating temperatures is higher (1.2382 mg/m2at 90 °C), room temperature has smaller content (0.6682 mg/m2and 0.9105 mg/m2at 20 °C and 30 °C, repectively). Content of VOCs in the white plastic lunch box increases gradually with temperature rising.

Evaluation of hydrocarbon emissions from heart- and sapwood of Scots pine using a laboratory-scale wood drier

Holzforschung ◽  
2004 ◽  
Vol 58 (6) ◽  
pp. 660-665 ◽  
Author(s):  
Peter Bengtsson ◽  
Mehri Sanati
Keyword(s):  
Volatile Organic Compounds ◽  
Organic Compounds ◽  
Scots Pine ◽  
Solid Phase ◽  
Hydrocarbon Emissions ◽  
Drying Process ◽  
Flame Ionization ◽  
Volatile Organic ◽  
Different Temperatures ◽  
Total Hydrocarbons

Abstract The subject of study is the emission of Volatile Organic Compounds (VOC) during the drying of wood. Heartwood and sapwood from Scots pine were dried at different temperatures (50, 70 and 90°C) in a laboratory kiln. The sampling method, Solid Phase Microextraction was used to collect the different volatile organic compounds during the drying. The gas chromatograph and mass spectrometer was used to identify and quantify the organic matter. The total hydrocarbons were measured with a flame ionization detector. Primarily, different monoterpenes were released during the drying process. 3-carene and α-pinene were most common and were also analytically quantified. The diterpene, pimaral, was found in an estimated large amount in the later stage of the drying process but was not exactly quantified. Large differences in both release behavior and total amount of released hydrocarbon between heart- and sapwood were obtained. Emissions of VOC from heartwood were of a magnitude approximately three times higher than that from sapwood.

scholarly journals Constraining a hybrid volatility basis set model for aging of wood burning emissions using smog chamber experiments

2016 ◽  
Author(s):  
Giancarlo Ciarelli ◽  
Imad El Haddad ◽  
Emily Bruns ◽  
Sebnem Aksoyoglu ◽  
Ottmar Möhler ◽  
...  
Keyword(s):  
Volatile Organic Compounds ◽  
Organic Compounds ◽  
Organic Aerosol ◽  
Reaction Rates ◽  
Box Model ◽  
Basis Set ◽  
Smog Chamber ◽  
Aerosol Mass ◽  
Volatile Organic ◽  
Different Temperatures

Abstract. Semi-volatile and intermediate volatility organic compounds (SVOCs, IVOCs) are not included in the current non-methane volatile organic compounds (NMVOCs) emission inventories but may be important for the formation of secondary organic aerosol (SOA). In this study, novel wood combustion aging experiments performed at different temperatures (263 K and 288 K) in a ~7 m3 smog chamber were modelled using a hybrid volatility basis set (VBS) box model, representing the emission partitioning and their oxidation against OH. We combine aerosol-chemistry box model simulations with unprecedented measurements of nontraditional volatile organic compounds (NTVOCs) from a high-resolution proton transfer reaction mass spectrometer (PTR-MS) and with organic aerosol measurements from an aerosol mass spectrometer (AMS). In so-doing, we are able to observationally-constrain the amounts of different NTVOCs aerosol precursors (in the model) relative to low-volatility and semi-volatile primary organic material (OMsv) which is partitioned based on current published volatility distribution data. By comparing the NTVOCs/OMsv ratios at different temperatures, we determine the enthalpies of vaporization of primary biomass burning organic aerosols. Further, the developed model allows for evaluating the evolution of oxidation products of the semi-volatile and volatile precursors with aging. More than 30,000 box model simulations were performed to retrieve the combination of parameters that fit best the observed organic aerosol mass and O:C ratios. The parameters investigated include the NTVOC reaction rates and yields as well as enthalpies of vaporization and the O:C of secondary organic aerosol surrogates. Our results suggest an average ratio of NTVOCs to the sum of non-volatile and semi-volatile organic compounds of ~4.75. The mass yields of these compounds determined for a wide range of atmospherically relevant temperatures and organic aerosol (OA) concentrations were predicted to vary between 8 and 30 % after 5 hours of continuous aging. Based on the reaction scheme used, reaction rates of the NTVOC mixture range from 3.0 × 10–11 cm3 molec−1 s−1 to 4.0 × 10–11 cm3 molec−1 s−1. The average enthalpy of vaporization of SOA surrogates was determined to be between 55,000 J mol−1 and 35,000 J mol−1 which implies a yield increase of 0.03–0.06 % K−1 with decreasing temperature. The improved VBS scheme is suitable for implementation into chemical transport models to predict the burden and oxidation state of primary and secondary biomass burning aerosols.

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