In order to determine whether there was any moisture in the recovered phenol crystals, a TGA test on the phenol crystals under nitrogen atmosphere was performed. As shown in Fig. 3(c), the TGA curves for both phenol samples overlapped, and the weight loss occurring between 33 1C and 115 1C was due to evaporation and sublimation of phenol crystals. There is no weight loss due to evaporation of water in the phenol crystal samples, indicating again the high purity of phenol crystals recovered.