Production of vinylidene chloride from the thermal decomposition of methyl chloroform.
Glisson-BT; Craft-BF; Nelson-JH; Meuzelaar-HL
Am Ind Hyg Assoc J 1986 Jul; 47(7):427-435
The thermal breakdown of methyl-chloroform (71556) (MC) to form vinylidene-chloride (75354) (VC) was investigated under laboratory conditions that approximate those found in industrial environments. Thermal degradation tests were carried out in the presence of air at temperatures of 206 to 605 degrees-C; a flow technique was used and the initial concentration of MC vapors was about 1900 milligrams per cubic meter. The effect of copper or glass beads was also tested. Gas chromatography and mass spectrometry analysis revealed that both VC and MC were present in samples obtained at 500 to 625 degrees-C; chloroethylene (75014) was detected at 575 degrees or more, while trichloroethylene (79016) was found in all samples. In the presence of glass beads decomposition began at 350 degrees and ended at 605 degrees; VC was obtained in almost stoichiometric amounts; with copper, the reaction started at 180 degrees and it ended at 442 degrees when MC was no longer found. The authors conclude that VC is formed in significant amounts when MC is decomposed thermally, information which has important implications for the field of industrial hygiene, considering the great toxicity of VC; further research is needed to evaluate the extent to which VC is formed from the breakdown of MC in the work environment.
NIOSH-Grant; NIOSH-Publication; Thermal-decomposition; Chlorinated-ethylenes; Chlorinated-hydrocarbons; Organic-solvents; Gas-chromatography; Mass-spectrometry; Equipment-design; Thermal-reactions
71-55-6; 75-35-4; 75-01-4; 79-01-6
American Industrial Hygiene Association Journal
Rocky Mountain Center for Occupational and Environmental Health, University of Utah D F C M, Room BC 106 Salt Lake City, Utah 84132