화학공학소재연구정보센터
Biotechnology Progress, Vol.23, No.1, 162-167, 2007
Target control of cell disruption to minimize the biomass electrostatic adhesion during anion-exchange expanded bed adsorption
Expanded bed adsorption (EBA) is an integrative unit operation for the primary recovery of bioproducts from crude feedstock. Biomass electrostatic adhesion often leads to bad bed stability and low adsorption capacity. The results indicate that effective cell disruption is a potential approach to reduce the biomass adhesion during anion-exchange EBA. Two common cell disruption methods (sonication treatment and high-pressure disruption with a French press) were investigated in the present work. The mean size of cell debris reduced dramatically during the cell disruption process, and the absolute value of the zeta potential of cell debris also decreased significantly as the mean size reduced. The biomass transmission index (BTI) obtained through the biomass pulse response experiment was used to quantitatively evaluate the biomass-adsorbent interaction. Combining the influences of zeta potential of adsorbent (zeta(A)), zeta potential of biomass (zeta(B)), and biomass mean size (d(B)), the parameter of (-zeta(A)center dot zeta(B)center dot d(B)) was explored as a reasonable indicator of biomass adhesion in expanded beds. A good linear correlation was confirmed between BTI and (-zeta(A)center dot zeta(B)center dot d(B)) for all biomass and cell disruption conditions tested, which was independent of the cell disruption methods. A target parameter (-zeta(A)center dot zeta(B)center dot d(B)) of 120 mV(2)mu m was derived for BTI above 0.9, which meant a very slight influence of biomass on the stability of the expanded bed. This criterion could be used as a rational control target for cell disruption processes in EBA applications.