Adsorption capadty

Since the adsorption of plant metabolite onto adsorbent is a strong function of pH, the effect of pH upon the adsorption capadty of a plant metabolite should be investigated to understand and quantify product adsorption. The pH dependence of indole alkaloids, yohimbine and ajmalicine, and berberine onto XAD-7 has been reported [ 16,20]. As a model system, XAD-7 was examined to quantify berberine adsorption, especially in terms of pH and concentration dependence, which were used for the in situ berberine separation in Thalictrum ru-gosum cultures [19, 20]. Dependence of berberine adsorption on pH and concentration was investigated as shown in Fig. 4. Equilibrium ratio (Q/C), an affinity of berberine, could be calculated by Eq. (1) ... 

Several recent studies sought to adsorb heavy metals onto magnetic nanoparticles. For example, the removal and recovery of Cr(VI) has been achieved by synthesized maghemite (Y-Fe203) nanopartides, and it is proved that Cr(VI) adsorption capadty of nanoscale maghemite compared favorably with other... 

The adsorption of an ion-pairing agent, picric acid, has been used to measure stationary-phase reprodudbility and ion-exdiange capadty 37, JOS). In this pnx ure a standard solution of picric acid in methylene-chloride is added to the polyamine modified stationary phase. The picric acid has a great affinity tow complexing with primary, secondary, and tertiary amines. Once washed to remove any unbound picric acid, the adsorbed picric acid is resorbed by the addition of triethylamine. The triethyla-mine picrate solution is quantitated spectophotometrically. 

In the case of adsorption, that s requiring substantial "time" (displacement volumes of clean air) to have the solvent concentration in air be less than the exposirre liinit. Yet, as shown Figures 4.24—4.26, the full capadty of an adsorption bed is sirtprisingly well used. 

This is not the total capadty of the activated carbon to hold solvent because the BET Equation allows for multilayer adsorption As used in the Langmuir Equation, this parameter can take on values no greater than s ax (as solvent Is present only in a monolayer)... 

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