Fixed-bed purification of ferulic acid from sugar-beet pulp using activated carbon: Optimization studies

Selective binding on a wood-based, chemically-activated carbon was considered following extensive enzymic hydrolysis of a sugar-beet pulp pectic extract. Adsorption and ethanolic elution were investigated, aiming at quantitative extraction and recovery of the released ferulic acid, at minimal cost and according to a given production rate. The effects of key operating parameters on the required amounts of adsorbent and eluent were assessed, and the prerequisites for optimal management of successive cycles were identified. Competition effects were analyzed, with special attention to residual feruloylated oligosaccharides. Complete saturation before regeneration was shown to yield the highest adsorption selectivity, desorption efficiency and purity of ferulic acid ( 50%). Crystallization from the eluate was achieved, allowing further purification of this phenolic compound for applications as a bioactive antioxidant or as a flavour precursor.