SOLUBILITY OF HYDROGEN-SULFIDE IN PURE WATER AND IN NACL SOLUTIONS, FROM 20-DEGREES-C TO 320-DEGREES-C AND AT SATURATION PRESSURES

The solubility of hydrogen sulfide in pure water and in NaCl solutions has been studied experimentally from 20 to 320-degrees-C and at satur ation pressures. Hydrogen sulfide solutions in equilibrium with their vapor phase were contained in a pressurized titanium bellows of known total volume. The bellows transmitted inside-vapor pressures via a the rmally stable oil (pressure medium) to a high-precision pressure senso r. Temperatures were measured by a sheathed thermocouple immersed into the oil surrounding the bellows. Values for the Henry constants were derived from measurements of equilibrium vapor pressure, volume, tempe rature, and bulk composition. The Henry constants agree well with prev iously published data up to about 200-degrees-C, but then deviate towa rds lower values (higher solubilities) at higher temperatures. Henry c onstants from 20 to 320-degrees-C and at saturation pressures may be o btained from the correlation log K(H)(T, P(sat,l)) = +0.6342702616e 3 + 0.2709284796e + 0 . T - 0.1113202904e - 3 . T2 - 0.1671907660e + 5 /T - 0.2619219571e + 3 . log T, where K(H) is in units of bar /molalit y and T in Kelvin. The experimental Henry constants have been fitted t o a scaled particle theory model and have been tested by a recently pr oposed linearization procedure. The salting-out effect of NaCl on H2S solubility is nearly independent of temperature up to about 250-degree s-C, but then increases sharply as temperatures approach the critical point of water. Skeleton tables to 365-degrees-C and for ionic strengt hs mu = 0, 1, 2, 3 have been prepared.