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The adsorption of l-α-glycerophosphocholine (GPC) by cation-exchange resin 001 × 7 was studied in a batch system. The adsorbent dosage, shaking speed, and adsorption temperature were investigated. An adsorption efficiency of more than 99.4% was obtained under optimal conditions. The kinetic data evaluated by the pseudo-second-order kinetic model fitted the experimental data better than those evaluated by the pseudo-first-order model. The rate constant k2 increased when the temperature increased, indicating the adsorption was endothermic in nature. The Langmuir and Freundlich isotherm models were used to analyze the adsorption equilibrium data, and it was found that the experimental data well fitted the Langmuir isotherm model. The thermodynamic parameters, enthalpy change (ΔG0), free energy change (ΔH0), and entropy change (ΔS0), were calculated. The value of ΔG0 was found to be in the range of −5.09 to −14.20 kJ mol−1, indicating that the adsorption was spontaneous and basically physisorption, and the positive values of ΔH0 and ΔS0 exhibited that the adsorption was endothermic and the randomness of the system increased during the adsorption.

Calcined sodium silicate could serve as an efficient and benign heterogeneous catalyst for the production of L-α-glycerophosphocholine from natural lecithin. The catalytic transesterification of natural lecithin by calcined sodium silicate proceeded to almost 100% conversion under the following conditions: sodium silicate amount of 6 wt%, reaction temperature of 65°C, lecithin concentration of 10.5 mmol/l, stirring intensity of 300 rpm, reaction time of 120 min. In addition, this catalyst could be separated completely by simple centrifugation and retained high activity after three re-uses. Compared to the previously reported catalysts, calcined sodium silicate, with the significantly important characteristics of non-toxicity and easy excretion from the human body, was beneficial to the benign production of L-α-glycerophosphocholine and its security as well as application in food and medicine fields.

The transesterification of phosphatidylcholine (PC for short) catalyzed by 12 kinds of low boiling point amines was examined under mild conditions to prepare l-α-glycerophosphocholine (GPC for short). The amines were confirmed as effective catalysts for GPC production, and the process using this kind of catalyst would be much simpler, since the recovery of the catalysts can be combined with the recovery of methanol by distillation. Three kinds of amines with boiling points lower than 50 °C and higher activities were applied to produce GPC, the yield of GPC could reach 90 % with a catalyst content of 2.4 %. The mechanism of the methanolysis catalyzed by the primary amine was proposed and the experimental data fit the equation model well. Isopropylamine showed better activity with higher yield of GPC and lower activation energy than others. Gas Chromatography and H NMR were used to analyze the product, which indicated that the product had high purity and there was no reaction between the catalyst and other materials. The catalyst could get similar effect to the fresh after repeated uses. [ABSTRACT FROM AUTHOR]