Abstract:
Adsorption  is  one  of  the  most  important  processes  in water  quality  control,   it  may  determine  the  fate  and  transport of pollutants  in the aquatic environment.  The adsorption of lead and zinc ions on the bed sediments of  river Kali in western Uttar Pradesh,  India has been studied. The role of the coarser sediment fraction (210-250  gm)  has been elucidated and compared to those of  the  clay  and  silt  fractions.  The  parameters  controlling  the uptake,   viz.,   initial   metal   ion   concentration,   solution   pH, sediment   dose,   contact   time,   and   particle   size   have   been evaluated.  The adsorption of metal ions increases with increasing initial  metal   ion  concentration.   The  optimum  contact  time   in which equilibrium is attained was found to De 45 min for both the metal  ions.  The  extent  of  adsorption  increases with  an  increase of pH.  The adsorption of metal  ions on the  sediments  follows  two phases,   a  linear phase of  adsorption  followed by a  flat  plateau section.   Further,   the  adsorption  of  metal  ions  increases  with increasing adsorbent doses and decreases with adsorbent particle size. The   two   geochemical   phases,   namely   iron  and  manganese oxide,  act  as  the active  support material  for  the adsorption of two metal  ions.