Influence of physicochemical variables on polymer adsorption in porous media.

HPAM type polymers and modifications with ATBS (Acrylamide Tertiary Butyl Sulfonated) units are used for EOR processes. Polymer adsorption is key to the success of these processes and is affected by variables such as molecular weight, hydrolysis, salinity, and permeability of the porous medium. Nevertheless, few studies corelate the dependence of these variables with adsorption. This work presents experimental results of the influence of variables on the dynamic adsorption of different polymers using sandstone type porous media. Modified polymers show adsorption less than 10 µg/g in low permeability and Sor condition. The adsorption of modified HPAM and HPAM polymers has an inverse relationship with molecular weight and permeability. At higher molecular weight, fewer pores are accessed due to their hydrodynamic radius and lower permeability, greater mechanical and hydrodynamic retention. Water salinity and hardness are directly related to adsorption, with less influence for modified HPAM. [ABSTRACT FROM AUTHOR]