1 Historical Use of Chlorinated Solvents and Their Stabilizing Compounds

This book deals with four the major chlorinated solvents: methyl chloroform, trichloroethylene, perchloroethylene, and dichloromethane. Carbon tetrachloride is also an important chlorinated solvent, but it was more commonly used between 1900 and 1960. Its primary use since then has been as an intermediate in the production of chlorofl uorocarbons and other chemicals (Doherty, 2000a; Shepherd, 1962). The more common names for these four major solvents include 1,1,1-trichloroethane or TCA (for methyl chloroform), trichloroethene or TCE (for trichloroethylene), tetrachloroethene or PCE (for perchloroethylene), and methylene chloride (for dichloromethane). Tables 1.1 and 1.2 present identifying information and chemical structures for the four major chlorinated solvents, as well as lists of synonyms and trade names. Solvent stabilizers have been added to a wide variety of solvents, including chlorinated and other halogenated solvents, petroleum solvents, ketone solvents, ether solvents, alcohol solvents, and others. This book focuses on the stabilizers for the chlorinated solvents, which were by far the most frequently used solvents for degreasing, dry cleaning, cold cleaning, and dozens of other industrial applications. This book also provides brief discussion of stabilizers for the following additional solvents: carbon tetrachloride, Freon 11, Freon 12, and Freon 113 (dichlorodifl uoromethane, trichlorofl uoromethane, and 1,1,2-trichloro-1,2,2-trifl uoroethane, respectively; Freon is a trademark name for chlorofl uorocarbons registered by E. I. Du Pont de Nemours and Company Corporation of Delaware) and new replacement solvents limonene, 1-bromopropane, siloxanes, terpenes.