ABSTRACT: Emissions of volatile organic compounds (VOCs) and carbonyls from residential coal combustion of five coals with different
maturities were studied in a simulated room. The coals were burned in form of honeycomb briquettes in a domestic coal stove,
one of the most common fuel/stove combinations in China. Through a dilution system, VOCs and carbonyls samples were collected
by canisters and silica-gel cartridges and analyzed by gas chromatography and mass spectrum (GC/MS) and high performance liquid
chromatography/ultraviolet (HPLC/UV), respectively. The results show that the bituminous coals with medium volatile matter
content produce the highest emissions while the anthracite yields the lowest. Among the identified carbonyls from the coal
smoke, the aromatic compounds (benzaldehyde, 2, 5-dimethylbenzaldehyde and p-tolualdehyde, m/o-tolualdehyde, benzene, m, p-xylene and trimethyl-benzene) were relatively abundant, which might be due to the molecular structure of the coal. For formaldehyde,
aromatic carbonyls and aliphatic alkanes, their concentrations increase up to the maximum values and then decrease with increasing
coal maturity. The total carbonyls and VOCs have the same tendency, which was observed for the emission factors of organic
carbon (OC), elemental carbon (EC), particulate matter (PM) and polycyclic aromatic hydrocarbons (PAHs) detected in the series
Keywordscarbonyls compounds-volatile organic compounds (VOCs)-residential coal combustion-emissions-coal maturity
Journal of Shanghai University (English Edition) 04/2012; 14(2):79-82.
ABSTRACT: A ternary-mobile phase program with acetonitrile, water and tetrahydrofuran was developed to identify and quantify 22 carbonyl compounds species by HPLC-UV. The analytical method succeeded in separating acrolein from acetone. Two sampling sites (industrial district and business district) were chosen to study carbonyl compounds levels in ambient air of Shanghai. The results indicated that formaldehyde, acetaldehyde, acetone and 2-butanone (C1-C4 carbonyl compounds) were the most abundant carbonyl compounds in ambient air of Shanghai. The four carbonyls together accounted for 78.95% (industrial district) and 77.63% (business district) of the total carbonyl compounds, respectively. In industrial district, the mean concentrations of formaldehyde, acetaldehyde, acetone and 2-butanone were 10.36, 15.32, 9.95 and 4.56 microg/m3, respectively; in business district, their mean levels were 10.00, 10.04, 7.80 and 2.81 microg/m3, respectively. So the mean levels of C1-C4 carbonyl compounds in industrial district were higher than in business district. The higher concentrations of the total carbonyls were also found in industrial district (53.64 microg/m3) than in business district (41.96 microg/m3). A similar diel variation occurred to the two districts that higher carbonyl concentrations were shown in morning peak and nighttime than in other three periods.
Huan jing ke xue= Huanjing kexue / [bian ji, Zhongguo ke xue yuan huan jing ke xue wei yuan hui "Huan jing ke xue" bian ji wei yuan hui.] 09/2009; 30(9):2701-6.
ABSTRACT: A sensitive and reliable method has been developed for the simultaneous determination of 20 airborne carbonyl compounds in the C(1)-C(10) range. The carbonyls were collected onto solid sorbent coated with pentafluorophenyl hydrazine (PFPH), followed by solvent extraction and gas chromatographic (GC)/mass spectrometric (MS) analysis of the PFPH derivatives. The sorbent is packed into two separate sections in a glass sampling tube. The two-section design allows convenient checking of collection efficiency and breakthrough. The sampling tube, with a coating amount of 971 nmol PFPH per 100 mg Tenax TA and operated at a sampling flow rate of 80 mL min(-1), collects the 20 carbonyls with efficiencies above 95%. Hexane extracts the collected carbonyls in their PFPH derivatives in the sampling tube with better than 95% extraction efficiency. It is necessary to let the sampling tube sit at ambient temperature for 3 days before solvent extraction to ensure complete derivatization of the carbonyls. The limits of detection (LODs) of the tested carbonyls are in the range of 3.7-11.6 ng per sample. The method has been field-tested both in ambient environment and in an indoor environment from burning mosquito-repellent incense. Eighteen carbonyls were detected in the ambient air samples with the exception of o-tolualdehyde and m-tolualdehyde, while all the 20 target carbonyls were found in the incense smoke. Compare field test with classical DNPH-HPLC/UV method, good agreement exited between the two methods for lower molecular carbonyls but PFPH method is found to be a better analytical method for determination of high molecular weight carbonyls.
Analytica chimica acta 04/2009; 635(1):84-93. · 4.31 Impact Factor
ABSTRACT: A method of compound-specific stable carbon isotopic analysis for the research about the sources of atmospheric formaldehyde was preliminary studied using gas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS) via 2, 4-dinitrophenylhydrazine (DNPH) derivatization. In order to evaluate the reproducibility, the accuracy and the carbon isotope effects of the method, formaldehyde with different delta 13C values were used to simulate the sampling procedure. The results show that the maximal analytical deviation for all formaldehyde 2, 4-dinitrophenylhydrazone is 0.3 per thousand and the average deviations between the determined and theoretical delta 13C values of them are 0.24 per thousand +/- 0.14per thousand (ranged from 0.03 per thousand to 0.35 per thousand), less than 0.5 per thousand the technical specifications of the GC/C/IRMS system. These mean that no carbon isotopic fractionation occurred during the procedure. The study for the indoor and outdoor atmospheric formaldehyde in the restaurant show that the stable carbon isotopic compositions are significant different for different sources of formaldehyde. The present method could provide valuable information about the sources of atmospheric formaldehyde.
Huan jing ke xue= Huanjing kexue / [bian ji, Zhongguo ke xue yuan huan jing ke xue wei yuan hui "Huan jing ke xue" bian ji wei yuan hui.] 09/2006; 27(8):1495-500.