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A screening-level methodology was developed for the evaluation of solute affinity for polymers that are candidate sorption resins. In this approach novel grafted polymer-silica resins were synthesized to produce poly(vinylpyrrolidone)-silica (PVP-Si) and poly(vinyl acetate)-silica (PVAc-Si) resins. The polymer-silica resins along with a number of commercially available polymer resins were used to evaluate the aqueous-phase adsorption of phenol, tetrachloroethene (PCE), trichloroethene (TCE), and chloroform. The polymer-grafted silicas were able to selectively remove pollutants from water with a covalently bonded polymer layer that has a high affinity for the target pollutant. The PVAc-silica resin had a sorption capacity for TCE and ChCl 3 as high as commercial poly(styrene) resin XAD-4; the PVP-Si resin had a sorption capacity for phenol higher than a commercial poly(vinylpyridine) resin (Reillex 425). PCE adsorption onto the PVAc-silica was comparable to the commercial poly(methacrylate) and poly(vinylpyridine) resins but less than the poly(styrene) resin. The results show that the Hildebrand solubility parameter along with the dipole moment of the polymer functional groups can be used for an initial screening-level assessment of polymer-solute affinity

The adsorption of the EPA priority pollutants trichloroethene (TCE) and chloroform (CHCl 3 ) from aqueous solutions onto activated carbon and macroporous polymeric resins was investigated over a wide concentration range. Over much of the concentration range studied, activated carbon adsorbed more TCE and CHCl 3 on a weight basis and on a surface area basis than did the polymer resins. At concentrations greater than 1000 μg/L, the adsorption capacity, on a surface area basis, for the different resins and for activated carbon was similar. The adsorption isotherms were fitted by the empirical Freundlich isotherm and the semiempirical isotherm of Jossens et al. The affinity of the solutes for the different resins was qualitatively described by a simple Hildebrand solubility parameter correlation

The control unit system consists of the combination of elements which direct and control the operation and functions of the system. It includes the stores and processing units as well as the elements of the man-machine interface. This paper describes the organization of these units, the processor order structure, and some rationale as to why certain design choices were made.

The uptake of phenol, toluene, chlorobenzene, and benzoic acid by several polymeric resins and activated carbon was investigated experimentally. Presentation of the sorption data in terms of the number of sorbed monolayers and fractional pore volume filled indicated that, for the polymeric resins, solute uptake cannot be viewed as only a surface adsorption phenomenon. It is suggested that the aqueous phase uptake of phenol, toluene, chlorobenzene, and benzoic acid by the polymeric resins is attributable, in part, to solute absorption. The present study also suggests that solute uptake is affected by the swelling of some of the polymeric resins in water.