Solubility of the pesticide diuron in organic nonelectrolyte solvents. Comparison of observed vs. predicted values based upon Mobile Order theory

Abstract

Experimental solubilities are reported at 25.0°C for diuron (also called 3-(3,4-dichlorophenyl)-1,1-dimethyl urea) dissolved in 49 different organic nonelectrolyte solvents containing ether-, chloro-, hydroxy-, ester-, methyl-, and tert-butyl-functional groups. Results of these measurements are used to test the applications and limitations of expressions derived from Mobile Order theory. For the 28 nonalcoholic solvents for which predictions could be made computations show that Mobile Order theory does provide fairly reasonable estimates of the saturation mole fraction solubilities. Average absolute deviation between predicted and observed values is 60.1%. Diuron solubilities in the alcohol solvents are used to calculate stability constants for presumed solute-solvent hydrogen bonds that are believed to occur in solution.Key words: pesticide, diuron solubilities, organic nonelectrolyte solvents, solubility predictions.