Immobilization Method to Separate Microalgae Biomass for Fatty Acid Methyl Ester Production

Abstract An immobilization method for simplified separation of cultured cells and their products from the growth media was developed. The growth rates of both immobilized and free cells of the microalga Chlorella vulgaris were compared. The free and immobilized cells reached nearly identical cell densities. The reported immobilization strategy uses a combination of matrices (sodium alginate (S A ), calcium alginate (C A ), and sodium carboxymethyl cellulose (C MC )) at different matrix/microalgae volumetric ratios of 0.3:1 and 1:1. The microalgae in the S A C A C MC /Mc (0.3:1) beads achieved the highest cell density. The cells immobilized in S A C A C MC /Mc (0.3:1) gave the highest lipid yield, as compared to the cells immobilized in S A . Pore size and membrane thickness analysis as well as surface images of S A C A C MC /Mc (0.3:1) showed that the mixed matrix had a unique structure favoring lipid production.