ABSTRACT
Carbon tetrachloride is a very useful nonhydrocarbon solvent and reagent, which, similar to CS2, is becoming progressively more dif‘cult to purchase. This is due to a decline in its traditional use as feedstock in the production of chloro¦uorocarbons, the latter being phased out under the Montreal Protocol (1989). Descriptions of laboratory preparations are almost nonexistent because of its low cost and availability in the past. The two main industrial methods of manufacture are exhaustive high-temperature (450°C-650°C) chlorination of hydrocarbons, especially methane [16], and chlorination of CS2 at 100°C-130°C [17-18]. Both are gas-phase reactions producing a large amount of by-products, and thus they cannot be run as ef‘cient batch processes in the laboratory. A prospective laboratory method is the original photolytic chlorination in distilling chloroform [19] (which is readily available, or can be prepared in the haloform reaction). However, the literature states that chloroform chlorinates with dif‘culty [19], and very little quantitative information is available that is of relevance to a laboratory preparation. A major concern is the extent of conversion achievable, the excess of chlorine required, the reaction rate in a typical laboratory setup, and percentage impurities in the ‘nal product.
