Separation of Volatile Fatty Acids by Simulated Moving Bed

Area of Science:

• Chemical Engineering
• Environmental Science
• Separation Technology

Background:

• Wastewater fermentation produces volatile fatty acids (VFAs) requiring efficient fractionation.
• Simulated Moving Bed (SMB) chromatography is a continuous separation technique with potential for VFA recovery.

Purpose of the Study:

• To evaluate the feasibility of SMB technology for fractionating VFAs.
• To demonstrate the separation of acetic and propanoic acids using SMB.

Main Methods:

• A lab-scale SMB unit with 6 columns packed with Amberlite XAD-4 resin was employed.
• Operating conditions were optimized to achieve high purity in extract and raffinate streams.
• A mathematical model was developed to describe the experimental data.

Main Results:

• Acetic and propanoic acids were successfully separated with purities of 97.8% and 100.0%, respectively.
• Recoveries reached 100.0% for acetic acid and 97.8% for propanoic acid.
• High productivities (2.93 and 2.81 mmol·g_ads^-1·day^-1) and low eluent consumption (0.075 L·mmol^-1) were achieved.

Conclusions:

• SMB technology is a feasible and efficient method for VFA fractionation from wastewater fermentation.
• The developed mathematical model accurately represents the SMB process for VFA separation.
• SMB offers a promising solution for recovering valuable VFAs.