75-44-5Relevant articles and documents
Hill, D. G.
, p. 32 - 40 (1932)
Crummett,Stenger
, p. 434,1083 (1956)
Rollefson
, (1933)
ULTRAVIOLET PHOTOOXIDATION FOR THE DESTRUCTION OF VOCS IN AIR
Bhowmick, Madhumita,Semmens, Michael
, p. 2407 - 2416 (1994)
Air stripping is an effective and economical process for removing volatile organic chemicals (VOCs) from contaminated water sources. However the air stripping process simply transfers the contaminants from the water to the air phase where they may continue to pose an environmental problem. In this study, the use of ultraviolet light (u.v.) photooxidation for treating the off gas from air stripping is examined. Subsequent papers will address linking u.v. photooxidation with air stripping in a closed loop stripping process. Fundamental studies are conducted to characterize the kinetics of the gas phase photooxidation of five volatile chlorinated alkanes and alkenes under different operating conditions. - Keywords: u.v.; volatile organic compounds; photooxidation; kinetics; gas phase; water treatment
Chatterji,Dhar
, p. 155 (1930)
A simplified [11C]phosgene synthesis
Bramoullé, Yann,Roeda, Dirk,Dollé, Frédéric
, p. 313 - 316 (2010)
A new flow-through system for the production of [11C]phosgene, a versatile labelling agent in radiochemistry for PET, is described. Cyclotron-produced [11C]CH4 is mixed with Cl2 and converted into [11C]CCl4 by passing the mixture through an empty quartz tube at 510 °C. The outflow is directed through a Sb-filled guard that takes out Cl2 and then, without intentional O2 addition, through a second empty quartz tube at 750 °C, giving rise to [11C]phosgene in 30-35% radiochemical yield.
CCl4 chemistry on the reduced selvedge of a α-Fe 2O3(0 0 0 1) surface: A scanning tunneling microscopy study
Rim, Kwang Taeg,Fitts, Jeffrey P.,Müller, Thomas,Adib, Kaveh,Camillone III, Nicholas,Osgood, Richard M.,Joyce,Flynn, George W.
, p. 59 - 75 (2003)
Scanning tunneling microscopy (STM) and low energy electron diffraction (LEED) were used to study the degradation of CCl4 on the reduced selvedge of a natural single crystal α-Fe2O3(0001) surface in ultrahigh vacuum. Before exposure to CCl4, STM images indicate that approximately 85% of the reduced surface exhibits a Fe 3O4(111) 2×2 termination, while the remaining 15% is terminated by 1×1 and superstructure phases. Images obtained after room temperature dosing with CCl4 and subsequent flashing to 600 K reveal that chlorine atoms are adsorbed only on surface regions with the Fe 3O4(111) 2×2 termination, not on 1×1 and superstructure regions. Chlorine atoms from dissociative adsorption of CCl 4 are observed to occupy two distinct positions located atop lattice protrusions and in threefold oxygen vacancy sites. However, in companion chemical labeling experiments, chlorine atoms provided by room temperature, dissociative Cl2 adsorption on this surface are found to occupy sites atop lattice protrusions exclusively. The clear dissimilarity in STM feature shape and brightness at the two distinct chlorine adsorption sites arising from CCl4 dissociation as well as the results of the Cl 2 chemical labeling experiments are best explained via reactions on a Fe3O4(111) 2×2 selvedge terminated by a 1/4 monolayer of tetrahedrally coordinated iron atoms. On this surface, adsorption atop an iron atom occurs for both the CCl4 and Cl2 dissociative reactions. A second adsorption site, assigned as binding to second layer iron atoms left exposed following surface oxygen atom abstraction resulting in the formation of phosgene (COCl2), only appears in the case of reaction with CCl4. The reaction mechanism and active site requirements for CCl4 degradation on iron oxide surfaces are discussed in light of this evidence and in the context of our previously reported results from Auger electron spectroscopy (AES), LEED, temperature-programmed desorption (TPD), and X-ray photoelectron spectroscopy studies.
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Fowler,Beaver
, p. 4186 (1953)
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Spurny, Z.
, p. 337 - 340 (1963)
Schulte, J. W.,Suttle, J. F.,Wilhelm, R.
, p. 2222 - 2227 (1953)
Silverman,Olofson
, p. 1313 (1968)
Chapman, A. T.
, p. 416 - 419 (1935)
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Chapman,Gee
, p. 1726 (1911)
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Chapman, A. T.
, p. 818 - 823 (1934)
Jacox,Milligan
, p. 866 (1965)
Kinetics of the Oxidation of Trichloroethylene in Air via Heterogeneous Photocatalysis
Jacoby, William A.,Blake, Daniel M.,Noble, Richard D.,Koval, Carl A.
, p. 87 - 96 (1995)
Trichloroethylene in solution with air is oxidized rapidly in the presence of irradiated titanium dioxide.Dichloroacetyl chloride (DCAC), which is formed as an intermediate during the trichloroethylene reaction, also undergoes photocatalytic oxidation.This paper describes the kinetics of these reactions and how operating conditions influence the observed reaction rates.Annular photocatalytic reactors with thin films of titanium dioxide catalyst were used to make kinetic measurements.Observations of the reaction rate of trichloroethylene were made while varying parameters such as catalyst loading, feed flow rate, feed composition, and ultraviolet light energy.The observed reaction rates are higher by several orders of magnitude than those previously reported in the literature, and an expression for the prediction of rate as a function of reactant partial pressure is provided.The rate of reaction of the DCAC intermediate is also discussed.Air is shown to be an optimum oxidant, and an optimum humidity is established.The reaction is shown to proceed indefinitely under dry conditions, supporting the existence of a chlorine radical propagated surface reaction.
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Dickinson,Leermakers
, p. 3852 (1932)
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Photocatalytic degradation of gaseous trichloroethylene on porous titanium dioxide pellets modified with copper(II) under visible light irradiation
Tashiro, Keigo,Tanimura, Toshifumi,Yamazaki, Suzuko
, p. 228 - 235 (2019/04/17)
Porous titanium dioxide pellets modified with copper(II) ion (Cu-TiO2) were synthesized by sol-gel method with dialysis for photocatalytic degradation of gaseous trichloroethylene (TCE) under visible light (VL) irradiation. TCE was completely degraded by passing the gas stream (mole fractions of oxygen and TCE were 0.2 and 1.75 × 10?4, respectively) at the flow rate of 25 mL min?1 through 0.2 g of the Cu-TiO2 pellets (Cu content: 0.1 atom%) calcined at 200 °C. TCE was converted mainly to carbon dioxide, dichloroacetic acid (DCAA), and inorganic chlorine species. Relatively small quantities of pentachloroethane (PCA) and trichloroacetaldehyde (TCAH) were detected as products on the Cu-TiO2 surface. Comparison with porous TiO2 pellets under ultraviolet irradiation revealed that more chlorinated products and less carbon dioxide were formed on Cu-TiO2 under VL irradiation. The mineralization of TCE to carbon dioxide was calculated to be only ca. 30.0%. It is noted that DCAA, PCA and TCAH were accumulated on the surface and were extracted with ethyl acetate. The porous Cu-TiO2 pellets show promise as the photocatalyst acting under VL irradiation for converting TCE gas to chlorinated compounds which can be used in industries.
A fluorescent probe Cou - Bu and its preparation and the ozone application in the
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Paragraph 0021; 0032; 0033, (2018/07/15)
A fluorescent probe Cou - Bu and its preparation and application of ozone in the detection. The invention provides a can be used for selectively detecting ozone molecules of the fluorescent probe. The main synthetic method is as follows: 7 - amino - 4 - methyl coumarin with triphosgene reaction to obtain the acyl chloride, generated product also and 3 - butene - 1 - ol to undergo esterification reaction, the final generation structure is Compound; under the action of the ozone molecules, generating 7 - amino - 4 - methyl coumarin, by using the difference between the front and the rear of the fluorescent reaction to the selectivity of the ozone molecule detection.
