Adsorption Capacity And Kinetics Study Of Aqueous Ethanol Purification Using Nigerian Woods Sawdust

E.A. Taiwo; S.I. Iragunima

E.A. Taiwo Separation Processes and Petrochemical Laboratory Department of Chemical Engineering, Obafemi Awolowo University, Ile-Ife Nigeria
S.I. Iragunima Separation Processes and Petrochemical Laboratory Department of Chemical Engineering, Obafemi Awolowo University, Ile-Ife Nigeria

Keywords: Adsorption, ethanol, sawdust, , diffusion and kinetics

Abstract

Bio-ethanol offers advantages of clean burning and reduced engine emission. However, its bioconversion technology is not cost- and energy-effective especially its purification pass the azeotropic point, hence the need for improving on the separation technology of its production. Adsorption by zeolites has been put forward as a means of concentrating the bio-ethanol above 95.5% w/w ethanol. This study investigates the capacity of some Nigerian woods sawdust as adsorbent for aqueous ethanol purification by liquid phase equilibrium adsorption process. To enhance adsorption capacity, the samples were modified using NaOH and H₂SO₄. Also, pseudo first- and second- order kinetics of the sorption process were studied. Out of the samples experimented; Cordia millenii, Milicea excelsia and Masilania accuminata demonstrated high capacity for water removal with percentage removal of 82, 80 and 75 percent, respectively. Upon acid modification, the capacity improved greatly. The adsorption process followed pseudo second order kinetics with particle-diffusion controlling the transport process. Modification with H₂SO₄ enhances the performance of the adsorbent.

Author Biographies

E.A. Taiwo, Separation Processes and Petrochemical Laboratory Department of Chemical Engineering, Obafemi Awolowo University, Ile-Ife Nigeria

E.A. Taiwo is a Senior Lecturer in the Department of Chemical Engineering, Obafemi Awolowo University, Ile-Ife. He holds a BSc. (Hons.) degree in Industrial Chemistry, while his M.Sc. and Ph.D. degrees are in Chemical Engineering. He is a registered engineer (R. Eng., COREN), a member of Nigeria Society of Chemical Engineer (MNSChE), Chemical Society of Nigeria (MCSN), Nigeria Society of Engineer (MNSE), American Institute of Chemical Engineers (MAIChE) and Polymer Institute of Nigeria (MPIN). He is currently the Ag. Director, Industrial Training Coordinating Unit, Obafemi Awolowo University, Ile-Ife. His research interests include Separation Processes and Petrochemicals, Raw Material Development and Process Synthesis.

S.I. Iragunima, Separation Processes and Petrochemical Laboratory Department of Chemical Engineering, Obafemi Awolowo University, Ile-Ife Nigeria

S.I. Iragunima is a postgraduate student in the Department of Chemical Engineering, Obafemi Awolowo University, Ile-Ife, Nigeria. She holds a B.Sc. degree in Industrial Chemistry from University of Port Harcourt, Choba, Nigeria. Her research interest is in Separation Processes and Petrochemicals.

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