Penggunaan gelombang ultrabunyi dalam pelbagai bidang termasuk proses pemisahan telah meningkat sejak akhir-akhir ini. Kajian ini melaporkan keberkesanan penggunaan gelombang ultrabunyi dalam meningkatkan pemisahan campuran binari dalam turus penyulingan. Campuran binari yang digunakan adalah metanol-air. Kesan keamatan gelombang bunyi yang berbeza iaitu 50, 100, 200 and 250 W/A.cm2 pada frekuensi 40 kHz terhadap keseimbangan wap-cecair (KWC) dikaji bagi mendapatkan nilai keamatan yang sesuai. Eksperimen juga dijalankan bagi mengkaji kesan frekuensi (25 and 68 kHz) terhadap data KWC. Didapati, penggunaan gelombang ultrabunyi berjaya meningkatkan proses pemisahan dengan meningkatkan nilai kemeruapan relatif. Purata kemeruapan relatif yang tertinggi bagi metanol-air iaitu 29.413 diperoleh daripada uji kaji yang menggunakan keamatan 200 W/A.cm2 dan frekuensi 25 kHz. Proses peronggaan dan kesan vakum yang wujud semasa perambatan gelombang ultrabunyi dalam cecair membawa kepada perubahan nilai kemeruapan relatif dan data KWC. Keputusan yang diperoleh menunjukkan keberkesanan penggunaan gelombang ultrabunyi bagi meningkatkan pemisahan campuran binari dalam turus penyulingan.
Kata kunci: Keseimbangan wap–cecair, metanol–air, gelombang ultrabunyi, kemeruapan relatif
The application of ultrasonic wave in various fields including separation process has increased predominantly. This paper reports the practicability of using ultrasonic wave to enhance separation of binary mixtures by distillation. The binary mixture utilized was methanol-water. The effect of different ultrasonic intensity at 50, 100, 200 and 250 W/A.cm2 with frequency of 40 kHz to vapor-liquid equilibrium (VLE) of methanol-water was investigated to obtain the most suitable operating intensity. Experimental studies were also carried out to investigate the frequency effect (25 and 68 kHz) to VLE data. It was found that the use of ultrasonic wave enhanced the separation process by increasing the relative volatility of components. The highest average relative volatility of methanol-water at 29.413 was obtained from experimental study using intensity 200 W/A.cm2 and frequency of 25 kHz. The changes in relative volatility and VLE were caused by cavitational activities and vacuum effect that occur during transmission of ultrasonic wave in liquid medium. The results from this study proved the practical feasibility of using ultrasonic wave to enhance separation of binary mixtures in distillation column.
Key words: Vapor–liquid equilibrium, methanol–water, ultrasonic waves, relative volatility
Effect of Solvents on the Relative Volatility of Binary Mixtures