Ultrafiltration polymeric membranes for the purification of biodiesel from ethanol

Abstract The emerging industry of biodiesel obtained from ethanol and vegetable oil, presents a number of difficulties in the purification step of the obtained esters. Current processes use large amounts of water to remove the by-product of the transesterification reaction. This paper presents an alternative to the washing process of biodiesel, which involves the use of ultrafiltration membranes resistant to solvents and alkalis. For that, two lab-made hydrophobic polymeric membranes were prepared from poly(vinylidene fluoride) and poly(sulfone) as main materials. The synthesized membranes were used to reduce glycerol content of biodiesel solutions obtained from semi-refined soybean oil and ethanol, catalyzed by sodium hydroxide. The poly(vinylidene fluoride) membrane reached a glycerol rejection up to 67% (at 30 °C and 5 bar) from a biodiesel sample with 0.5 wt % of water added. Under the same operation conditions, the poly(sulfone) membrane showed a lower separation performance, with glycerol rejection of 48%. Moreover, stability tests demonstrated that poly(vinylidene fluoride) membrane was more stable to solvents, alkalis and temperature, compared to the poly(sulfone) membrane. A remarkable flux recovery after more than 45 cycles of biodiesel permeation (≈105 hs) was verified in poly(vinylidene fluoride) membrane, indicative of the high stability and low fouling of the membrane.

[1]  W. Kunz,et al.  The extension of microemulsion regions by combining ethanol with other cosurfactants , 2013 .

[2]  P. A. Arroyo,et al.  Influence of oil quality on biodiesel purification by ultrafiltration , 2015 .

[3]  C. Querini,et al.  Ethyl ester production by homogeneous alkaline transesterification: influence of the catalyst. , 2011, Bioresource technology.

[4]  Denny K. S. Ng,et al.  Review of evolution, technology and sustainability assessments of biofuel production , 2014 .

[5]  N. A. Ochoa,et al.  SPC/PVDF membranes for emulsified oily wastewater treatment , 2009 .

[6]  S. M. Nascimento,et al.  Biodiesel purification using micro and ultrafiltration membranes , 2013 .

[7]  M. Maciel,et al.  Liquid–Liquid Equilibria in Ternary and Quaternary Systems Present in Biodiesel Production from Soybean Oil at (298.2 and 333.2) K , 2012 .

[8]  I. M. Atadashi,et al.  High quality biodiesel obtained through membrane technology , 2012 .

[9]  Siti Kartom Kamarudin,et al.  Overview on the current trends in biodiesel production , 2011 .

[10]  D. F. Evans,et al.  Properties and structure of three-component ionic microemulsions , 1984 .

[11]  Marek Gryta,et al.  Influence of morphology of PVDF capillary membranes on the performance of direct contact membrane distillation , 2010 .

[12]  Miguel Mattea,et al.  Ultrafiltration of vegetable oils: Degumming by polymeric membranes , 2001 .

[13]  Junghui Chen,et al.  Ultrafiltration of triglyceride from biodiesel using the phase diagram of oil–FAME–MeOH , 2009 .

[14]  A. Abdulkareem,et al.  The Production and Characterization of Ethyl Ester (Biodiesel) from Waste Vegetable Oil as Alternative to Petro Diesel , 2014 .

[15]  Marc A. Dubé,et al.  Glycerol removal from biodiesel using membrane separation technology , 2010 .

[16]  V. Rajal,et al.  Comparison of the performance of ultrafiltration and nanofiltration membranes for recovery and recycle of tannins in the leather industry , 2016 .

[17]  A. Mohammad,et al.  Application of polymeric solvent resistant nanofiltration membranes for biodiesel production , 2010 .

[18]  I. M. Atadashi,et al.  Biodiesel separation and purification: A review , 2011 .

[19]  A. Phan,et al.  Determination of the kinetics of biodiesel saponification in alcoholic hydroxide solutions , 2015 .

[20]  L. Ramos,et al.  Ethanolysis of Refined Soybean Oil Assisted by Sodium and Potassium Hydroxides , 2007 .

[21]  Norman N. Li.  Advanced membrane technology and applications , 2008 .

[22]  Pedro Prádanos,et al.  Pore size distributions based on AFM imaging and retention of multidisperse polymer solutes: Characterisation of polyethersulfone UF membranes with dopes containing different PVP , 2001 .

[23]  José M. Encinar,et al.  Ethanolysis of used frying oil. Biodiesel preparation and characterization , 2007 .

[24]  R. Ackrill,et al.  The Growth of Biofuels in the 21st Century: Policy Drivers and Market Challenges , 2014 .

[25]  R. Kesting.  Synthetic Polymeric Membranes: A Structural Perspective , 1985 .

[26]  M. Ulbricht,et al.  Characteristics, performance and stability of polyethersulfone ultrafiltration membranes prepared by phase separation method using different macromolecular additives , 2009 .

[27]  Andrew L. Zydney,et al.  Microfiltration and Ultrafiltration: Principles and Applications , 1996 .

[28]  Myeong-Jin Han,et al.  Thermodynamic and rheological variation in polysulfone solution by PVP and its effect in the preparation of phase inversion membrane , 2002 .

[29]  J. Marchese,et al.  Deacidification and solvent recovery of soybean oil by nanofiltration membranes , 2013 .

[30]  Soon Huat Tan,et al.  Membrane technology as a promising alternative in biodiesel production: a review. , 2012, Biotechnology advances.

[31]  C. Querini,et al.  High performance purification process of methyl and ethyl esters produced by transesterification , 2013 .

[32]  N. A. Ochoa,et al.  Effect of hydrophilicity on fouling of an emulsified oil wastewater with PVDF/PMMA membranes , 2003 .

[33]  Pierre Aimar,et al.  Experimental study of the effects of hypochlorite on polysulfone membrane properties , 2006 .