Adsorption glycerine

In glycerin, the dispersion appears to be stable and behaves as a shear thinning fluid. However, the viscosity does not vary monotonically with silica concentration, instead decreasing initially before increasing at higher concentrations (Fig. 38). The phenomena reflect offsetting effects of adsorption, the reduction in the solution viscosity due to depletion of polymer... 

The desalted sample is then evaporated to dryness either by rotary evaporation under reduced pressure at 40°C or by lyophilisation. The addition of a small quantity of glycerine (e.g. 100 pi to 100 ml of sample) prior to reduction in volume avoids any losses of sugars by wall-induced condensation reactions or adsorption (Dawson and Mopper, 1978a). The residue is then taken up in a small volume of 20% aqueous ethanol and may be stored refrigerated if not analysed immediately by liquid chromatography. 

Significant amounts of activated carbon are consumed in systems applied for purification of pharmaceuticals. The main application of the carbon here is separation of numerous antibiotics, vitamins, and steroids from fermentation broths by adsorption, usually followed by solvent extraction and distillation. Furthermore, activated carbons are used as purification media for other key phannaceutical chemicals as, for instance glycerin. The pharmaceutical industry often uses activated carbons for water purification process (usually in a combination with other purification technologies like deionization [149]) and for the thorough elimination of potential impurities from intravenous solutions prior to packaging [146]. 

NIRS in internal reflection mode has also been used to study in situ low-level surfactant adsorption reactions (sub-monolayer coverage) using reactive internal reflection elements [175]. Standard errors of 0.04% were reported for the determination of 0.25-1.25% additives in nylon (cubes and films) [294]. Turley et al [309] used NIRS to determine ethylene oxide content and glycerin additive concentrations in ethylene oxide/propylene oxide copolymers. NIR diffuse reflectance spectroscopy was used to analyse up to 10% paper (cellulose) in agglomerate plastic waste (PE 60%, PS 20%, PP 15%, PVC 4%) [161]. For pigment applications, cfr, ref. [310]. 

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