Biosorption of monovalent and divalent ions on baker's yeast.
Biosorption of monovalent ions Na+ and K+, by deactivated protonated yeast (Saccharomyces cerevisiae) at controlled pH, was compared with biosorption of divalent ions Ca2+ and Mg2+ to help to understand the underlying bindingmechanisms. The adsorption for monovalent ions was accompanied by H+ release. Divalent ions were sorbed by proton displacement, and also an additional mode not accompanied by release of H+. The sorption uptake of both monovalent and divalent metal ions increased with pH in the range 3-7 peaking at 6.75. Equilibrium sorption isotherms at pH = 6.75 showed that the totalmaximum biosorptive capacity for metal ions decreased in the following order: Ca > Mg > Na > or = K.
Vasudevan
Padma
P
Centre for Rural Development and Technology, Indian Institute of Technology, Delhi, Hauz Khas, New Delhi. padmav@rdat.iitd.ernet.in
Padmavathy
V
V
Dhingra
S C
SC
D000327:Adsorption; D002412:Cations; D004305:Dose-Response Relationship, Drug; D006863:Hydrogen-Ion Concentration; D007477:Ions; D011134:Polysaccharides / Q000737:chemistry; D012441:Saccharomyces cerevisiae / Q000378:metabolism*
D002412:Cations; D007477:Ions; D011134:Polysaccharides