Experimentally determined Henry's Law coefficients of phenol, 2-methylphenol and 2-nitrophenol in the temperature range 281-302 K

The Henry's Law coefficient is a key physical parameter in the partitioning, and hence environmental fate, of a chemical species between air and water. Despite the acknowledged polluting potential of phenol, 2-methylphenol (ocresol) and 2-nitrophenol, there is extremely poor agreement in the literature of their Henry's law coefficients and, in particular, no apparent systematic measurement of the variation with temperature. Here, a temperature-controlled column-stripping method was employed to determine Henry's Law coefficients for these compounds over the temperature range 281-302 kappa. Coefficients were derived from regression fits to the observed rates of losses from the liquid phase as a function of column depth in order to explicitly take account of potential non-attainment of equilibrium between liquid and gas phases. Temperature dependent expressions summarising the Henry's Law coefficients of phenol, omicron-cresol and 2-nitrophenol over the stated temperature range are ln H(M atm(-1)) = 5850/T - 11.6, In H(M atm(-1)) = 5850/T - 15.4 and In H(M atm(-1)) = 6270/T - 16.6, respectively (to within 15% of all measured values in this work). A thorough comparison with the previous literature-published values has been undertaken. (C) 2002 Elsevier Science Ltd. All rights reserved.