All other
reagents were of suitable analytical grade and deionised water was
used to prepare solutions and for washing apparatus. The physicochemical
properties of PAEs, MPEs and PA used in these studies are
provided in Table 1.
To avoid contamination, plastic equipment was not used in any
sampling or experimental processes and all glass apparatus was
soaked in chromic acid solution for at least 12 h, washed with
deionised water and baked at 180 ◦C for not less than 4 h.