IONIC-STRENGTH AND BUFFER EFFECTS IN THE ELIMINATION-REACTION OF 1,1,2,2-TETRACHLOROETHANE

The rate constant for the abiotic reaction of 1,1,2,2-tetrachloroethan e in aqueous solution has been studied as a function of ionic strength , buffer composition, temperature, and pH. The rate of reaction is fou nd to be independent of ionic strength and buffer composition, with th e parent compound quantitatively converted into trichloroethene by a b ase mediated elimination reaction for values of pH > 3.5. The Arrheniu s parameters for the elimination reaction are log(10) A = 16.32 +/- 0. 40; E(a) = 95.0 +/- 2.5 kJ/mol. No evidence for a neutral hydrolysis r eaction was found, indicating that the rate constant for such a reacti on is < 2 x 10(-7)s(-1) at 90 degrees C.