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U.S. Patent: 6177599 - Method for reducing formation of polychlorinated aromatic compounds during oxychlorination of ... The oxychlorination process consists of contacting the hydrocarbon reactant with oxygen or oxygenated gas and at least a portion of externally obtained hydrogen chloride in the presence of the oxychlorination catalyst in a heated reaction zone operated at from 150.degree. wherein chlorinated hydrocarbon is recovered from the effluents of the reaction zone, the process is characterized by the fact that the hydrogen chloride is pretreated with a means for removal of the aromatic hydrocarbons. This liquid phase reaction of ethylene and chlorine as taught in '747 is conducted at the boiling point of the EDC liquid in the presence of a metal chloride catalyst and added aromatic hydrocarbon, such as benzene. www.everypatent.com /comp/pat6177599.html   (4275 words)

Pesticide Toxicity Profile: Chlorinated Hydrocarbon Pesticides   (Site not responding. Last check: 2007-10-12) Chlorinated Hydrocarbons are a group of chemicals composed of carbon, chlorine and hydrogen. As with most of the chlorinated hydrocarbons, DDT has been banned for use in the United States, but is still used in some developing countries for combating insect vectors of disease. Mammalian toxicities for chlorinated hydrocarbon pesticides are shown in Table 1. edis.ifas.ufl.edu /PI090   (1006 words)

Organochloride - Wikipedia, the free encyclopedia The simplest form of organochlorides are chlorinated hydrocarbons. Most low molecular weight chlorinated hydrocarbons such as chloroform, dichloromethane, dichloroethene and trichloroethane are useful as solvents. Chlorinated alkenes are useful monomers used in the preparation of a variety of materials. en.wikipedia.org /wiki/Chlorinated_hydrocarbon   (310 words)

Laminated sheet structures   (Site not responding. Last check: 2007-10-12) A laminate structure of claim 2 consisting of one ply of linear polymer of ethylene and one ply of a composition consisting essentially of a blend of a chlorinated hydrocarbon elastomer with an ethylene/propylene copolymer elastomer. A laminate structure of claim 2 consisting of a core ply of linear polymer of ethylene and of two outer plies of a composition consisting essentially of a blend of a chlorinated hydrocarbon elastomer with an ethylene/propylene copolymer elastomer. A method of claim 14 wherein the chlorinated hydrocarbon elastomer is chlorosulfonated polyethylene; the ethylene/propylene copolymer elastomer is an EPDM elastomer; and the polymer of ethylene is polyethylene. www.well.com /~youlee/spacer_batch_coil_annealing/laminated_sheet_structures.html   (419 words)

American College of Medical Toxicology Carbon tetrachloride,chloroform, methylene chloride, tetrachloroethylene, trichloroethylene, and trichloroethane are all chlorinated hydrocarbons that may cause CNS and respiratory depression. The presence of a chlorinated hydrocarbon, particularly an agent with a high ratio of the number of chlorine atoms to molecular weight may be quite noticeable on radiographs. Analytical detection of halogenated hydrocarbons is not routinely available from clinical laboratories but special reference laboratories may be able to perform a halogenated screen that will qualitatively detect the presence of some of these hydrocarbons. www.ijmt.net /ijmt/1_1/1_1_4.html   (1453 words)

DNR - DDT And Other Chlorinated Hydrocarbon Pesticides Included in the chlorinated hydrocarbon insecticide group are DDT (dichlorodiphenyl trichloroethane), methoxychlor, aldrin, dieldrin, chlordane, toxaphene, endrin, heptachlor, and lindane (gamma isomer of benzene hexachloride (BHC)). Levels of chlorinated hydrocarbons are occasionally found in avian species that have died, but this is a rare occurrence. Mortality in wildlife due to chlorinated hydrocarbon poisoning is seldom observed in Michigan anymore. www.michigan.gov /dnr/0,1607,7-153-10370_12150_12220-26633--,00.html   (997 words)

Chlorine and Chlorinated Hydrocarbons | Effluent Guidelines | USEPA Chlorinated hydrocarbon manufacturers considered in this rulemaking are based in part on the type of manufacturing process involved. Chlorine production as a by-product of other manufacturing processes such as magnesium production are also being considered though they are not included in 40 CFR Part 415. Chlorinated hydrocarbons in the OCPSF point source category that are manufactured by processes similar to the production for EDC and VCM are part of this rulemaking. www.epa.gov /waterscience/guide/cch   (871 words)

Report (No 22) on the ninth Steering Committee Meeting, Gaborone, Botswana, 13-16 February 1996 Chlorinated hydrocarbons are present at parts per trillion level (ng/l) in water samples and at parts per billion or parts per million levels (ng/g or μg/g) in sediments and biota, thereby requiring highly specific, sensitive and reliable analytical methods for carrying out such trace and ultra-trace measurements. Organochlorine pesticides, especially DDT and its derivatives were the first generation of chlorinated hydrocarbons to be used for control of agricultural pests and human diseases (vector control) in the North African sub-region since the 1950s. The relatively low levels of chlorinated insecticides in the Mahmoudiah Canal (drinking water source for Alexandria) and the waste water might be due to the cessation of use of this group of insecticides in Egypt since 1971 because of their persistence. www.fao.org /docrep/008/v3640e/V3640E06.htm   (9344 words)

WDNR - Chlorinated Paraffins Synonyms: Chlorinated alkanes; chlorinated hydrocarbon waxes; chlorinated paraffin waxes; chlorinated waxes; chloroalkanes; chlorocarbons; chloroparaffin waxes; paraffin, chlorinated; paraffins, chloro; paraffin waxes, chlorinated; paroils, chlorinated; poly- chlorinated alkanes; polychloro alkanes. Chlorinated paraffins are used around the world in widespread applications such as plasticizers in plastics (e.g., PVC), extreme pressure additives in metal working fluids, flame retardants and additives in paints. Chlorinated paraffins may be released into the environment from improperly disposed metal-working fluids containing chlorinated paraffins or from polymers containing chlorinated paraffins. dnr.wi.gov /environmentprotect/pbt/chemicals/shortchain.htm   (477 words)

Microseeps: Technical Articles In addition, because chlorinated aliphatic hydrocarbons may be used as electron acceptors or electron donors, in competition with other acceptors or donors, isopleth maps showing the distribution of these compounds and their daughter products can provide evidence of the mechanisms of biodegradation working at the site. During this process, the chlorinated hydrocarbon is used as an electron acceptor, not as a source of carbon, and a chlorine atom is removed and replaced with a hydrogen atom. Because chlorinated aliphatic hydrocarbons are used as electron acceptors during reductive dechlorination, there must be an appropriate source of carbon for microbial growth in order for this process to occur. www.microseeps.com /html/tech_chlorinatedsolvents.html   (1667 words)

Search Results for "Hydrocarbon" The hydrocarbons differ both in the total number of... ...A hydrocarbon, C6H3(CH3)3, occurring in petroleum and coal tar or synthesized from acetone and used as a solvent. ...A crystalline hydrocarbon, C14H10, extracted from coal tar and used in the manufacture of dyes and organic chemicals. www.bartleby.com /cgi-bin/texis/webinator/sitesearch?FILTER=&query=Hydrocarbon   (259 words)

B. Chlorinated Solvents   (Site not responding. Last check: 2007-10-12) Chlorinated solvents have been widely used until recently because they are very effective cleaners and are safe in the sense that they are nonflammable. Chlorinated solvents have always been very effective cleaning chemicals for metal finishers because of their great solvency for oils and greases, their high volatility that results in rapid drying and no residual film, and their non-flammable nature. A number of alternatives to chlorinated solvents have been developed in the metal finishing industry including various types of aqueous cleaning solutions; organic compounds with varying level of water miscibility such as terpenes, esters, and glycol ethers; non-chlorinated petroleum hydrocarbons; alcohols; supercritical fluids; and carbon dioxide snow and pellets. www.nmfrc.org /fdocs/rdcsi/secIIB.htm   (835 words)

chlmetal The contamination of groundwater with chlorinated solvents is a well recognized problem that has proven resistant to resolution. Chlorinated solvents are denser than water which allows them to sink through groundwater aquifers, they have relatively high levels of solubility, and free phase chlorinated solvents react with clays causing shrinkage and cracking, permitting the solvents to pierce what were thought to be impenetrable aquitards. Irrespective, in-situ bioremediation of chlorinated solvents was intensely researched in the 1980's, with advances such as cometabolism. 2the4.net /chlmetal.htm   (1004 words)

Catalytic hydrodehalogenation of polyhalogenated hydrocarbons  (Technology/Intellectual Property Profile) Although the time of contact at the initiation temperature may vary depending on the halogenated hydrocarbon and the hydrogen donor used in the feedstock, the inventors have found that about one hour at the initiation temperature is satisfactory. Negligible chlorine content in the exhaust gas was found; therefore, the total extent of the spectrophotometric complex formation was attributed to the HCl content of the exhaust gases. Typically, large amounts of chlorine representing at least 97% of the total theoretically available chlorine under reaction conditions of complete dechlorination of starting material were found. www.uta.edu /ra/real/editprofile.php?pid=984&onlyview=1   (5669 words)

Battelle PNWD Bioremediation - What is In Situ Bioremediation? Chlorinated hydrocarbons can undergo biotransformation via three different mechanisms: use of the chlorinated compound as an electron acceptor, use of the chlorinated compound as an electron donor, or by cometabolism (fortuitous reaction providing no benefit to the microorganisms) One or more of these mechanisms may be active at a given site. When a chlorinated aliphatic hydrocarbon is biodegraded via cometabolism, the degradation is catalyzed by an enzyme or cofactor that is fortuitously produced by the organisms for other purposes. In general, reductive dechlorination is the process whereby a chlorine atom is removed from the chlorinated compound and is replaced with a hydrogen atom. bioprocess.pnl.gov /isb_defn.htm   (1343 words)

hydrocarbon — FactMonster.com The hydrocarbons differ both in the total number of carbon and hydrogen atoms in their molecules and in the proportion of hydrogen to carbon. Many hydrocarbons are useful as fuels; they burn in air to form carbon dioxide and water. Many important compounds are derived from hydrocarbons, either by substitution or replacement by some other chemical group or element of one or more of the hydrogen atoms of the hydrocarbon molecule, or by the addition of some element or group to a double or triple bond (in an unsaturated hydrocarbon). www.factmonster.com /ce6/sci/A0824706.html   (470 words)

EEA - Glossary - chlorinated hydrocarbon Chlorinated hydrocarbon (CHC) is a generic term given to compounds containing chlorine, carbon and hydrogen. The human and environmental health risks of chlorinated hydrocarbons depend on the compound in question. As a general statement, exposure to chlorinated hydrocarbon has been associated with suppression of the immune system and cancer. glossary.eea.eu.int /EEAGlossary/C/chlorinated_hydrocarbon   (108 words)

Railway lubricating oil - Patent 4734211 However, environmental aspects of incorporating quantities of chlorinated hydrocarbons into railway diesel engine lubricants indicate that reduced use of chlorinated compounds and use of non-chlorinated compounds to provide silver protective properties is preferable. In the event a mixture of a polyhydroxy compound and a chlorinated paraffin is utilized as a silver wear inhibitor additive package, the inhibitor combination package is incorporated with the lubricant oil composition in sufficient amount to inhibit substantially against wear of bearing surfaces. The silver wear inhibitor compounds, i.e., the polyhydroxy compounds, the chlorinated compounds and mixtures thereof, are on the basis of active components. www.freepatentsonline.com /4734211.html   (4981 words)

Laboratory Services Light hydrocarbon compound analyses are also utilized to determine areas of natural gas leakage spills, the presence of gas seepage from deep seated oil and gas reservoirs and/or the leakage from oil and gas well casings. C5+ (pentane-xylenes+) hydrocarbons analyses which yield a quantitative measure of the actual volume of "gasoline type " vapors present in near surface soils and/or water are conducted on a 30-meter capillary column. Elevated concentrations of methane, ethane and ethylene (ethene), in areas where elevated concentrations of chlorinated hydrocarbon compounds are present, are indicative of anaerobic biodegradation of chlorinated solvents. eti-geochemistry.com /lab   (1151 words)

Tech ID #313 Information Page Characterizing the extent of chlorinated hydrocarbon contamination, controlling remediation treatment processes, and monitoring of regulatory compliance frequently require hundreds or thousands of analyses. The system is capable of detecting chlorinated hydrocarbons in the range of 0.2-25 ppm and up to 500 ppm with an internal dilution feature that is incorporated into the instrument. Development of a condensed phase sampler for the instrument to enable detection of chlorinated hydrocarbons in water and sludges is continuing. www.external.ameslab.gov /cmst/CMSTSite/Projects/pp_313.html   (659 words)

Division of Environmental Quality   (Site not responding. Last check: 2007-10-12) Chlorinated hydrocarbon insecticides, such as chlordane, DDT, toxaphene, and dieldrin were the main family of insecticides used following their introduction after World War II. Problems associated with DDT, as well as many chlorinated hydrocarbons, involved their tendency to concentrate in the fat of humans, livestock, aquatic foodchains, and wildlife. Methoxychlor is another chlorinated hydrocarbon permitted for use in the United States. www.fws.gov /contaminants/Issues/DDT.cfm   (395 words)

Reclamation of components from grinding swarf - Patent 3997359 After agitating the swarf with the methanol, the methanol and water is removed in a well-known manner as by filtration or centrifuging and the swarf, now substantially free of water is washed with a hydrocarbon or chlorinated hydrocarbon to dissolve the lubricant phase of the coolant-lubricant, kerosene being a satisfactory hydrocarbon solvent for this purpose. In the case of the previously-described water-based lubricant-coolant witn emulsified mineral oil, the screened swarf is intimately mixed with a hydrocarbon such as kerosene or a chlorinated hydrocarbon solvent to which has been added a synthetic surfactant such as linear alkyl sulfonate or nonylphenoxypoly (ethyleneoxy) ethanol, these being typical but not exclusive. The surfactant, which is premixed with the hydrocarbon or chlorinated hydrocarbon solvent, is added to promote an emulsion of the water portion of the lubricant-coolant with the solvent while also effecting removal of some of the lubricant. www.freepatentsonline.com /3997359.html   (2180 words)

RMP Report: Technical Report of the Chlorinated Hydrocarbon Workgroup The mission of the Chlorinated Hydrocarbon Workgroup (CHCWG) was to develop recommendations for a Regional Monitoring Program (RMP) sampling design that optimally meets the objectives of the Program with regard to chlorinated hydrocarbons (CHCs) and to provide a formal justification for the recommended design. The lower chlorinated congeners found in Aroclor 1248 would not be expected to persist in the Bay over the long term, nor would the fingerprint of a specific Aroclor be expected to be distinctly apparent after years of mixing in the Bay. Chlorinated hydrocarbon pesticides and polychlorinated biphenyls in sediment cores from San Francisco Bay. www.sfei.org /rmp/reports/chc_recs/chc_recs.html   (6234 words)

Chlorine Formation in Thermal Oxidizers Thermal Oxidizers (TOX units) are often used to dispose of chlorinated hydrocarbons (hydrocarbon molecules which contain at least one atom of chlorine). The simplest chlorinated hydrocarbon is Methyl Chloride, which consists of one atom of carbon, three of hydrogen and one of chlorine. This means that most of the chlorine atoms will leave the TOX furnace as HCl (hydrogen chloride gas molecules), but a considerable part will be in the form of Cl (chlorine gas molecules). www.banksengineering.com /chlorine.htm   (644 words)

Landfills and Water Quality Management While the concentrations of various chlorinated hydrocarbons in runoff waters and in Bay waters have been measured as part of a conventional stormwater runoff monitoring program, the data generated from these programs has not revealed whether the constituents are present in forms that can be adverse to the beneficial uses of Upper Newport Bay. In estimating the critical concentrations of chlorinated hydrocarbons and certain heavy metals, such as mercury, in fish tissue that represent a hazard for human consumption, estimates have to be made regarding the amount of fish containing the hazardous chemicals that are consumed on a routine basis. Aldrin Aldrin is a chlorinated hydrocarbon pesticide that is banned for further use because of its persistence and potential to be a health hazard to increase the cancer risk to those exposed to it. www.gfredlee.com /unb_wq.html   (17378 words)

W.T. Tysoe: Research The strategy applied to investigating this chemistry is to probe the nature of the reaction on a model catalyst, generally an atomically clean metal sample, in ultrahigh vacuum and to relate this chemistry to the catalytic reaction occurring at higher pressure to obtain an understanding of the reaction pathway. One of the main additives to these lubricants, chlorinated hydrocarbons, improve their behavior under conditions of extreme pressure and prevent seizure of the contacting surfaces. It has been shown that the chlorinated hydrocarbon added to the lubricating fluid thermally decomposes at the hot interface to yield a solid lubricant layer consisting of an iron chloride and carbon. www.uwm.edu /People/wtt/research.htm   (624 words)

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