Instrumentation
Absorption spectra and absorbance measurements were
achieved by a Jenway spectrophotometer (model 6715, UK) using
1 cm glass cells. A Metrohm digital pH meter (model 632,
Switzerland) with a combined glass electrode was used to measure
pH values. A centrifuge (Behsan, Iran) was used to accelerate the
phase separation process. A thermostatic water bath (Memmert,
Germany) was used to maintain the temperature in CPE
experiments.