摘要 |
Ethylterphenyls, liquid at normal temperatures, having a b.p at atmospheric pressure above 400 DEG C. and an average M.W. of 290 to 350, are prepared by injecting gaseous ethylene into a liquid mixture containing at least one terphenyl and a Friedel-Crafts catalyst, the reaction being carried out with agitation at atmospheric pressure without the addition of a solvent for the terphenyl, the reactants being maintained at 100 DEG - 180 DEG C. The catalyst used is preferably a metallic chloride, e.g. AlCl3, ZrCl4 or FeCl3 and is used preferably in amounts of 0.3% to 3.0% by weight of the material to be alkylated. The gaseous ethylene may contain 1 to 10% by volume of a promoter, e.g. dry gaseous hydrogen chloride or a gaseous aliphatic chloride. The product alkylate may be fractionated and the overhead fraction may be recycled to the reactor. The average degree of alkylation (this term is defined) is between 2 and 4. The ethylterphenyls, which may be in isomeric mixture may be used as heat transfer liquids for moderators in atomic reactors.
|