1,1,1 -trichloroethane conductivity

The demonstration unit was later transported to the CECOS faciHty at Niagara Falls, New York. In tests performed in 1985, approximately 3400 L of a mixed waste containing 2-chlorophenol [95-57-8] nitrobenzene [98-95-3] and 1,1,2-trichloroethane [79-00-5] were processed over 145 operating hours 2-propanol was used as a supplemental fuel the temperature was maintained at 615 to 635°C. Another 95-h test was conducted on a PCB containing transformer waste. Very high destmction efficiencies were achieved for all compounds studied (17). A later bench-scale study, conducted at Smith Kline and French Laboratories in conjunction with Modar (18), showed that simulated chemical and biological wastes, a fermentation broth, and extreme thermophilic bacteria were all completely destroyed within detection limits. 

Groundwater. Under aerobic conditions, 1,1,1-trichloroethane slowly degraded to 1,1-dichloroethane (Parsons and Lage, 1985 Parson et al, 1985). Based on a study conducted by Bouwer and McCarty (1984), the estimated half-life of 1,1,1-trichloroethane in groundwater three months after injection was 200-300 d. 

In a 1995 treatability study conducted for the U.S. Department of Energy (DOE) Savannah River facility, a cost estimate was prepared for an FTO system with a flow rate of 400 standard cubic feet per minute (scfm) using natural gas to maintain process temperatures. Costs were estimated at 0.72/lb. For the purposes of this estimate, the inlet concentration was assumed to be 400 ppm of trichloroethylene (TCE), perchloroethylene (PCE), and 1,1,1-trichloroethane (TCA). Capital costs were estimated at 160,000. Capital costs were amortized over 10 years, not over the time required to remediate the site. This cost estimate found FTO to be more cost effective than thermal catalytic technologies due to lower operating and maintenance costs (D125122, p. 10). 

The first addition step—specifically, the direct catalytic chlorination of ethylene [Eq. (6.40)]—is almost always conducted in the liquid phase.188-190 272 273 1,2-Dichloroethane is used as solvent with ferric chloride, an efficient and selective catalyst. Ionic addition predominates at temperatures of 50-70°C. The conversion is usually 100% with 1,2-dichloroethane selectivity higher than 99%. The primary byproduct is 1,1,2-trichloroethane, believed to be formed by subsequent radical chlorination of 1,2-dichloroethane. A low amount of oxygen (below 1%), therefore, is added to the chlorine feed to suppress radical side reactions. 

Halogenated Hydrocarbons. A few halogenated hydrocarbons were studied by the usual procedure, using mixtures in air over the platinum filament. Neither dichlorodifluoromethane (CC12F2) nor 1,1-dichloro-ethene yielded a measurable ion current at temperatures up to 900°C. 1,1,1-Trichloroethane yielded a modest ion current, but the results were erratic and not reproducible. There was some indication that the halogen compounds changed the behavior of the filament. Consequently, no further experiments with halogenated compounds were conducted. This erratic behavior was in contrast with the very reproducible results with hydrocarbons. 

Prengle et al. (1996) studied the photooxidation by UV/H202 of waterborne hazardous Q-Q compounds in drinking water. Their work was conducted in a photochemical batch stirred-tank reactor, with medium pressure mercury arc immersion lamps of 100 and 450 W, covering the visible UV range, (578.0 to 222.4 nm). Tetrachloromethane, tetrachloroethane, dichloro-ethane, dichloroethene, trichloroethane, trichloroethene, and benzene were the compounds studied. Dark oxidation rates and photooxidation rates were determined. The latter rate constants were 104 to 10s greater than those under dark conditions. 

The conductometric electrode consists of two platinum plates, as with a standard laboratory conductivity cell. Despite the appearance of a black deposit on the surface of the electrodes, no deterioration in performance was found. An occasional washing in trichloroethane was used. In contrast, glass/calomel electrodes often require unexpected exchange and a spare electrode must always be available. 

The effects of aquifer anisotropy and heterogeneity on NAPL pool dissolution and associated average mass transfer coefficient have been examined by Vogler and Chrysikopoulos [44]. A two-dimensional numerical model was developed to determine the effect of aquifer anisotropy on the average mass transfer coefficient of a 1,1,2-trichloroethane (1,1,2-TCA) DNAPL pool formed on bedrock in a statistically anisotropic confined aquifer. Statistical anisotropy in the aquifer was introduced by representing the spatially variable hydraulic conductivity as a log-normally distributed random field described by an anisotropic exponential covariance function. 

Ocular administration of 1,1,1-trichloroethane caused only mild eye irritation in rabbits (Duprat et al. 1976 Krantz et al. 1959 Marzulli and Ruggles 1973 Torkelson et al. 1958). The study by Marzulli and Ruggles (1973) was a survey in which 10 laboratories conducted the Draize eye test in rabbits using 1,1,1-trichloroethane and reported little or no eye irritation. 

The women initially complained of numbness in their limbs, and subsequent nerve conduction studies showed alterations in peripheral nerve activity. The effect was diagnosed as primarily a distal sensory peripheral neuropathy. These cases were unusual because the effect was greater in the hands than in the feet, the reverse of most peripheral neuropathies. Sural nerve biopsies in two of the women performed 3-4 years after diagnosis revealed chronic neuropathy (axonopathy and myelinopathy) (Liss 1988). The authors did not establish a causal relationship with 1,1,1-trichloroethane. 

A. Braun is conducting a 13-week dietary study of 1,1,1-trichloroethane in rats and mice (CRISP Database 1992). The study will include hematological and clinical chemistry examinations, sperm morphology and vaginal cytology examinations, and urinary metabolite analysis. 

Exposure Levels in Humans. 1,1,1-Trichloroethane has been detected in human tissues and expired air. Studies have recently determined that the potential for exposure of the general population may be significantly higher inside the home. Additional information that correlates the lifestyle of the individual with the total body burden of 1,1,1-trichloroethane would aid in reducing future exposure to the general population. This information is necessary for assessing the need to conduct health studies on these populations. 

Under anaerobic conditions, 1,1,2-trichloroethane is reported to undergo dehalogenation. In order to establish whether this is a biologically mediated reaction and not simply an abiotic reaction catalyzed by free iron or iron porphyrin at low redox potential, Dow Chemical conducted 28-day studies in sterile solutions (Klecka and Gonsior 1983). They found that ppm concentrations of 1,1,2-trichloroethane did not undergo nonenzymatic dehalogenation in a sterile, anaerobic solution at pH 7 or when a sulfide redox buffer or hematin was added (Klecka and Gonsior 1983). 

Recent data available from a NASA Lewis Research Center test program [ ], utilizing trichloroethane, together with data from a liquid-hydrogen test program conducted at this facility P], have shed considerable light on the mechanism of stratification. While the primary objective of the NASA work was the determination of the effects of nuclear radiation... 

In a Study conducted by Scott (1990) only ten of one hundred and thirty six compounds detected in landfill gas were present at concentrations above their relevant TLV s or OES s at any time during the study period. This work (Scott, 1990), also suggested that any potential health risk posed by landfill gas would be likely to be associated with the period immediately following waste emplacement. Also, according to Hoather and Wright (1989), the most significant trace components are hydrogen sulphide, vinyl chloride, benzene, toluene, trichloroethane, methyl mercaptan and ethyl mercaptan, all of which have been found at concentrations above their TLV s. 

Table 9.3 Statistical copolymers of FOA with hydrocarbon, vinyl monomers. Polymerizations were conducted at (59.4 0.1)°C and (34.8+0.05) MPa for 48 h in CO2. Intrinsic viscosity was determined in 1,1,2-trifluoro-trichloroethane (Freon-113) at 30 °C.

The pruity of halogenated solvents is determined using a thermal conductivity or flame ionization detector, a column made from 3.2 mm stainless tubing packed with 30 wt% silicone fluid on 80-100 mesh diatomaceous earth or using capillary colurtm. Admixtures in 1,1,1 -trichloroethane are determined using a thermal conductivity or hydrogen flame detector. Column from copper or stainless steel is packed with Chromosorb W HP with 20% polydimethylsiloxane. ... 

DDT is an acronym for dichlorodiphenyl trichloroethane, but should be named more precisely as 2,2-bis(p-chlorophenyl)-l,l,l-trichloroethane (see Fig. 16.1 for its structure). A German chemist, Othmar Zeidler synthesized this compound in 1874 while he was pursuing his PhD. And it had remained as that, a new synthesized compound, for a quite while. Carl Muller of J. R. Geigy (a Swiss Pharmaceutical company, now Chiba-Geigy) discovered in his pursuit of insecticides that the compound synthesized by O. Zeidler was extremely toxic to houseflies. Numerous tests were conducted, and the compound DDT was found to be an excellent insecticide. Besides it is cheap to make. This was the time when the World War II was raging. DDT was then used to control lice on soldiers on the front. In earlier wars, more soldiers died of typhus (bom by louse) than by bullets. The WWII was really the first war in history where more soldiers died actually from bullets than the louse-bom disease, thanks to DDT. DDT was then considered to be a savior to control many kinds of harmful pests. C. Muller was awarded a Nobel prize in 1948. 

It was not possible to conduct toxicological examinations on five of the 106 interview-confirmed cases and six of the 113 interview-confirmed controls. Among those who were toxicologically examined, seven of the 101 interview-confirmed cases (6.9%) and one of the 107 interview-confirmed controls were positive for volatile substances. Details of those who were positive on toxicological examination are shown in Table 15. In all of the cases, the substances identifled were consistent with the product which was reported to have been abused most recently (1,1,1-trichloroethane in six cases who had last abused typewriter correction fluids, toluene in the remaining case who had most recently abused petrol). The control was positive for toluene for reasons which could not be satisfactorily explained. 

A secondary aromatic alcohol in (5) form, (5)-a-phenylethanol, did not serve as a substrate of the esterification by PEG-lipase. From the result obtained above, it can be concluded that PEG-lipase exhibited higher stereoselectivity for chiral secondary alcohols with a longer carbon chain or a phenyl group. In order to test the applicability of PEG-lipase to optical resolution of racemic alcohols, we conducted the esterification with PEG -lipase in 1,1,1-trichloroethane using racemic a-phenylethanol and dodecanoic acid [86]. As is shown in Fig. 13, the amount of the substrate, (R,5)-a-phenylethanol, decreased... 

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