ARS | Publication request: Membrane recovery of phenolic acid co-products from biomass

Submitted to: Association for the Advancement of Industrial Crops Conference
Publication Type: Abstract
Publication Acceptance Date: June 30, 2008
Publication Date: September 7, 2008
Citation: Holser, R.A., Harry O Kuru, R.E., Sarah Kate, B., Joy, P. 2008. Membrane recovery of phenolic acid co-products from biomass. Association for the Advancement of Industrial Crops Conference.

Technical Abstract: The technology to convert lignocellulosic biomass to biofuels is progressing with parallel efforts to develop processes to recover valuable natural products and generate additional revenue from these associated co-products. The lignified components of plant tissues contain phenolic acid structures such as ferulic and p-coumaric acids that possess bioactive properties and represent potential co-products, e.g., antioxidant and antimicrobial agents. The large-scale separation and recovery of these compounds from biomass prior to the conversion of the cellulosic portion depends upon an economical separation scheme. The objective of this investigation was to identify a membrane material that could separate ferulic acid from an aqueous extract and demonstrate a feasible approach to recover the acid as a co-product in a biomass conversion facility. Dilute aqueous solutions of ferulic acid were prepared and tested with five different types of membrane materials in a screening procedure to test the ability of each membrane to selectivity retain the analyte, ferulic acid. The tested membrane materials included Teflon, Nylon, regenerated cellulose, polyether sulfone (PES), and polyvinylidene fluoride (PVDF). Test solutions of known ferulic acid concentrations were passed through the different membranes. The membrane permeates were collected and analyzed by HPLC-DAD using a C18 column with isocratic methanol as the mobile phase. Column eluents were monitored at 280 nm and UV spectra were collected by scanning under the detected peaks. The results of this study demonstrated that a nylon membrane was able to retain 80% of the ferulic acid present in the aqueous solution as determined by analysis of the membrane permeate. Retention of ferulic acid by the other membrane materials was not significant. The use of a nylon membrane to recover ferulic acid provides an inexpensive separation scheme to obtain ferulic acid as a co-product from an aqueous process stream. Membrane separations are advantageous because they are not capital or energy intensive operations and are environmentally benign.