Preferential adsorption of organic compounds onto activated carbon from dilute aqueous solutions is studied to develop a comprehensive theoretical basis for predicting the adsorption of structurally different isomers for different homologous series. The fundamental multidimensional approach of the solvophobic (c+) thermodynamic theory is further refined and used to correlate the extent of adsorption for the comprehensive theory with the overall standard net free energy change (ACnet/RT) for the association-adsorption reaction in solution, and for the simplified theory with the cavity surface area of the solute (TSA).Experimental adsorption isotherms of two homologous series (12 aliphatic alcohols and 21 aliphatic ketones) were measured and used to test and compare the c+ theory with seven independent parameters characterizing the sorbates. Several experimental innovations for measuring equilibrium adsorption isotherms are introduced to reduce the possible loss of sorbate during the procedure and to provide reproducible and reliable results.Comparing the coefficients of linear correlation (r), the results for 12 aliphatic alcohols give greater than 99% confidence that the r-values are different for hGnet/RT and molecular weight (MW). For the 15 aliphatic ketones, greater than 90% confidence interval is obtained for different r-values for TSA and MW, These results support the contention that simple structural modifications of aliphatic homologous compounds can be used to predict the effect of solutesolvent-sorbent interactions on adsorption. The c+ theory can thus be used to rankorder adsorption intensity of these compounds from the aqueous phase onto activated carbon. SCOPEDuring the past century, little effort has been expended in trying to understand the fundamentals underlying the process of adsorption of solutes from a solvent onto a solid sorbent (Miller, 1980a,b). Several simultaneous developments, such as the need to clean our surface water, the development of extremely sensitive analytical techniques, and the wide use of reverse-phase liquid chromatography, have spurred interest in this field.Most researchers used a phenomenological approach in which equilibrium adsorption models mostly derived from gas-and vapor-phase adsorption, were used to describe adsorption from the liquid phase. This approach either a priori ignored the presence of the solvent, assuming that the dominant interaction was between the solute and sorbent, or included the solvent effect without specifying its role quantitatively. Freundlich (1926), in his classic monograph, describes the first attempts 90 years ago by Traube and others to include the solvent-solute interaction effect through interfacial tension at the solid-liquid interface. Although Defay et al. (1966) a comprehensive interaction theory among solute, solvent, and sorbent is still lacking. Recent attempts to include the solventeffect in aqueous phase adsorption include a semiempirical approach based on partial solubility parameters called the net adsorption energy appro...

Growth of a hybridoma culture, along with production of monoclonal antibody, was demonstrated over extended periods in polysulfone hollow fiber membrane modules. The molecular weight cutoffs of the membranes were 70,000, 50,000, and 100,000 daltons. The hybridoma cell line, designated 65/26, produced IgG (2b/kappa) directed at mouse thymus cell surface antigen, TL.1. Cell growth occurred in the shell space of the reactor, using supplemented RPMI 1640 (20% fetal bovine serum) supplied from a separate reservoir vessel through the hollow fiber lumen. The reservoir contained 125 mL media, which was changed every 4 days. Concentrations of immunoglobulin were determined by an enzyme immunoassay (using protein A and alkaline phosphatase-labeled antibody conjugate). For the 10K, 50K, and 100K hollow fiber membrane modules, the maximum IgG concentrations detected in the 2.5-mL shell space were 47.5-80, 510, and 740 mug/mL, respectively. In the 125-mL reservoir for the 100K hollow fiber membrane module, the IgG concentration was measured at 260 mug/mL These values compare with an IgG concentration of 1 mug/mL when grown in a standard tissue culture flask and 3.2-7.6 mug/mL when grown in 100 ml media in a spinner flask. In addition, 10K and 50K hollow fiber membrane modules were run in a mode that decreased the fetal bovine serum supplement with time. Differences between these systems suggest that it is possible to obtain high IgG accumulation rates, both during and after the exponential growth phase of the hybridoma population.

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