Influence of Extraction-Purification Conditions on Final Properties of Sodium Alginates Obtained from Brown Algae (Macrocystis pyrifera)

C.G. GÓMEZ; M.V. PÉREZ; M. RINAUDO; M.A VILLAR

Rio de Janeiro, Brasil

Simposio; World Polymer Congress, 41st International Symposium on Macromolecules, MACRO 2006; 2006

Asociación Brasileña de Polímeros (ABPol)

Alginates production is based on a series of ionic exchange reactions. However, extraction conditions such as temperature (T), time (t), and pH affect the extraction yield as well as cations other than sodium retained by alginate. At the conditions studied, a maximum yield of 35 % was obtained. The extraction yield improved with an increase in both the time and extraction temperature. On the other hand, higher temperatures of extraction were necessary when the extraction pH was decreased. Semidiluted solutions of sodium alginates extracted at low pH shown viscosities higher than expected due, probably, to a higher content of polyvalent cations such as Ca2+ and Mg2+, among others.