| Glycerin is an essential chemical material, which was widely used in organic chemical, macromolecule syntheses, detergent & cosmetics, textiles, dopes, tobacco products, foods, Pharmaceuticals, and so on. Nowadays, the output can't satisfy the requirement of glycerin in China. Sweetwater, the diluted glycerin solution what came from the hydrolysis of oil-fat. It is the by-product of the companies which produced fatty acid. However, most of the companies considered it as the wastewater. The aim of the project is to recover the glycerin, and it not only can achieve the economic benefits, but only it can solve the pollution problems. The research was developed by three main steps. Firstly, we should find the analysis method of the glycerin. Secondly, we do many static adsorption experiments to find the valid macroporous adsorption resin. Finally, we do many dynamic experiments to check the adsorption rule, as it can instruct the adsorption engineering practice.A High Performance Liquid Chromatography method was developed for rapid determination of glycerin in low concentration sweet water. The peak symmetry is well in the right chromatography condition. The calibration curve was linear with R~2=0.9999. Average recoveries of glycerin for real samples were 99.83%-101.59% (n=9) while the relative standard deviation was 0.21% (n=6). The method developed is fast and simple to use, and provides a direct, accurate and reliable means for the rapid determination of glycerin in sweet water. It is feasible to be used in the quality control of glycerin production and application.A comparison the adsorption of eight macroporous resins, including the static equilibrium adsorption isotherms and the adsorption thermodynamic properties. Equilibrium data for the adsorption of glycerin on HPD500 within temperature range of 303K~323K and investigative concentration range had been obtained, which were correlated with Freundlich equation well. The biggest adsorption volume of HPD500 reached 190mg per gram dry resin. Comparative static adsorption research showedthat the bigger specific surface and polar macroporous resins may adsorb more glycerin. The results showed that the adsorption for glycerin on macroporous resins proved to be a physical exothermic process, and the adsorption ability of resins enhance with the decrease of temperature. Estimations of the isosteric enthalpy change of adsorption, free energy change, and entropy change of adsorption are reported, and the adsorption behaviors are reasonably interpreted.A comparison of the adsorption between the hyper-crosslinked resin HPD850 and the macroporous resins HPD300 was investigated. Thermodynamics data of indicates that the mechanism of the HPD850 was the same with the HPD300. What's more, the adsorption volume of the hyper-crosslinked resin is not higher than the macroporous resin. The mechanism of the phenomena should be explained in the future.The dynamic adsorption experiments were investigated in the different flow rates, and the dynamic adsorption for the six resins was also investigated. The suitable flow rate was 0.5BV/h was acquired by the comparison of high flow rate and low flow rate. And the breakthrough curve of the six resins was also investigated. The results indicate that the bigger specific surface and polar macroporous resins may adsorb more glycerin in the precondition that the pore diameter of the resin is suitable. This conclusion is the same with the result which was obtained from the static adsorption.
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