EQUILIBRIUM STUDIES IN NATURAL-WATERS - SPECIATION OF PHENOLIC-COMPOUNDS IN SYNTHETIC SEAWATER AT DIFFERENT SALINITIES

Interactions between some phenolic compounds and macro-constituents of synthetic seawater (Na+, K+, Ca2+, Mg2+, Cl-, and SO42-), at 20, 35, and 45 parts per thousand salinity, have been investigated potentiometrically by using the [H]-glass electrode. The formation constants of phenol, o- and p-cresol, o- and p-nitrophenol complexes with sodium, potassium, calcium, and magnesium ions have been determined in the ionic strength range 0 less than or equal to I less than or equal to 1 mol/L. A comparison between the apparent protonation constants of phenols determined in synthetic seawater, and those simulated by a suitable complex formation model, is discussed. The possibility of calculating, by simulation, the apparent protonation constants of some chlorophenolic compounds in synthetic seawater is also reported.