本文之研究為水-酚-對甲酚-鄰甲酚四成份系統分別在323.15 K以及353.15 K兩個溫度下進行液液相平衡實驗。 對甲酚之製造過程中,為將甲酚從產物中分離出來,必須將水相及有機相分開,所以在製程模擬中必須有完整之液液平衡數據,因此本研究之目的乃在於提供完整之實驗數據及合適之液液相平衡預估模式,以提供製程模擬之用。 同時,針對所得到的實驗數據選擇不同的液相模式進行迴歸,在本研究中選擇UNIQUAC及NRTL二種模式迴歸計算而得到最佳參數。 由實驗結果得知三成份系統有機相與水相之互溶性隨溫度提高而提高。且於323.15 K時UNIQUAC模擬結果較佳,而於353.15 K時NRTL模擬結果較佳,而四成份系統無論在323.15 K或353.15 K下所得模擬結果為NRTL較佳。 In this study, the LLE experiments for quaternary system of water - phenol - p-cresol - o-cresol were conducted at 323.15 K and 353.15 K respectively. In the process of manufacturing p-cresol, the aqueous phase should be separated from the organic phase for next step of purifying p-cresol. Thus a complete LLE phase behavior is essential for process design and simulation. The purpose of this study is to provide complete LLE data as well as selecting the suitable models to represent the experimental data. And our correlation results show that the UNIQUAC and NRTL are the models. As a result of study, we know that the mutual miscibility of aqueous phase and organic phase is increased as the temperature increase.