Generation with trichloroethylene

An emulsion, formed during extraction of a strongly alkaline liquor with trichloroethylene, decomposed with evolution of the spontaneously flammable gas, dichloro-acetylene [1]. This reaction could also occur if alkaline metal-stripping preparations were used in conjunction with trichloroethylene degreasing preparations, some of which also contain amines as inhibitors, which could also cause the same reaction [2], Apparently accidental contact of the solvent with potassium hydroxide solution led to generation of flames in the charging port of a stirred reactor [3], See Tetrachloroethylene Sodium hydroxide... 

Alkynylsulfides. A synthesis from alkyl- or arylthiols is accomplished through 5-alkylation with trichloroethylene, complete dechlorination to generate the thioethynyllithium species, and C-alkylation. 

Sodium hydroxide reacts with trichloroethylene, forming explosive mixtures of dichloroacetylene. When heated with phosphorus pentoxide, a violent explosion can result (Mellor 1946, Suppl. 1971). Phosphorus boiled with caustic soda solution can produce phosphine, which ignites spontaneously in air. Amphoteric metals such as aluminum, zinc, and tin react with sodium hydroxide, generating hydrogen, which may form explosive mixtures in air. 

An alternative method of cleaning involves vapor degreasing the unit by spraying the cold internal surfaces with trichloroethylene vapor generated by boiling the solvent in an external vessel. The principle of operation is not unlike the soxhlet extraction of materials. 

Decomposition of trichloroethylene can occur upon contact with naked flames, red-hot surfaces, hot elements of electric heaters, or intense UV light with the generation of acidic and highly-toxic products. The presence of reactive contaminants, e.g. acids, strong alkalis, highly-reactive metals, may also result in decomposition to similar products. 

NOTE - Petrochemical plants also generate significant amounts of solid wastes and sludges, some of which may be considered hazardous because of the presence of toxic organics and heavy metals. Spent caustic and other hazardous wastes may be generated in significant quantities examples are distillation residues associated with units handling acetaldehyde, acetonitrile, benzyl chloride, carbon tetrachloride, cumene, phthallic anhydride, nitrobenzene, methyl ethyl pyridine, toluene diisocyanate, trichloroethane, trichloroethylene, perchloro-ethylene, aniline, chlorobenzenes, dimethyl hydrazine, ethylene dibromide, toluenediamine, epichlorohydrin, ethyl chloride, ethylene dichloride, and vinyl chloride. 

Smoke Generating Compositions. A soln of 3 parts of cnioronaphthalene in trichloroethylene is slurried with 23 parts of powd Zn and 4 parts of kieselguhr, the solv evapd, the granulated prod mixed with 50 parts of AP and 20 parts of Amm chloride, and the mixt pressed in a mold to give a waterproof smoke generator (Ref 14). 

Many groundwaters are contaminated with the cleaning solvents trichloroethylene (TCE) and perchloroethylene (PCE). They are two of the most common organochlorine compounds found in Superfund sites. Radiation-induced decomposition of TCE in aqueous solutions has been the subject of several recent studies [15-20]. In most of the referenced studies, the complete destruction of TCE was observed. Dechlorination by a combination of oxidative and reductive radiolysis was stoichiometric. Gehringer et al. [15] and Proksch et al. [18] have characterized the kinetics and mechanism of OH radical attack on TCE and PCE in y-ray-irradiated aqueous solution. Trichloroethylene was readily decomposed in exponential fashion, with a reported G value of 0.54 pmol J-1. A 10 ppm (76 pM) solution was decontaminated with an absorbed dose of less than 600 Gy. For each OH captured, one C02 molecule, one formic acid molecule and three Cl- ions were generated. These products were created by a series of reactions initiated by OH addition to the unsaturated TCE carbon, which is shown in Eq. (45) ... 

Three feed streams were investigated, as shown in Table 2. Feed A was generated from a gas containing 1000 ppm C5-C9 hydrocarbons, which was blended with an equal volume of VOC-free air saturated with water vapor. Feed B, containing Cj-C chloronated hydrocarbons was generated in the same way similarly for Feed C, which contained 50 ppm trichloroethylene in addition to hydrocarbons. The components and relative proportions were selected on the basis of typical VOC contents from air strippers at several installations [2]. Note there are feeds with only hydrocarbons, with only chlorocarbons, and with a mixture of the two. 

Direct chlorination of vinyl chloride generates 1,1,2-tnchloroethane [79-00-5] from which vinylidene chloride required for vinylidene polymers is produced. Hydrochlorination of vinylidene chloride produces 1,1,1-trichloroethane [71-55-6], which is a commercially important solvent. Trichloroethylene and perchloroethylene are manufactured by chlorination, hydrochlorination, or oxychlorination reactions involving ethylene. Aromatic solvents or pesticides such as monochlorobenzene, dichlorobenzene, and hexachlorobenzene are produced by reaction of chlorine with benzene. Monochlorobenzene is an intermediate in the manufacture of phenol, insecticide DDT, aniline, and dyes (see Chlorocarbons a>td Chlorohydrocarbons.)... 

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