| (R,S)-?-phenethylamine is an important class of organic synthesis intermediates.Substances derived from it have an important role in chemical production.Optically active R-?+?-phenethylamine or S-?-?-phenethylamine has different properties due to different spatial structures,and has potential research in the fields of organic synthesis and asymmetry value.This paper constructedternary solid-liquid equilibrium systems D-?-?-tartaric acid-S-?-?-phenethylamine+D-?-?-tartaricacid-R-phenethylamine+wateratT=298.15K?308.15K?318.15K?328.15K,solubility phase diagram under normal pressure.In the corresponding phase diagram at each temperature,the phase diagram area can be divided into four parts,namely:D-?-?-tartaric acid-S-?-?-phenethylamine and D-?-?-tartaric acid-R-?+?-phenethylamine unsaturated region,D-?-?-tartaric acid-S-?-?-phenethylamine crystalline region,D-?-?-tartaricacid-R-?+?-phenethylamine crystalline region And the co-crystallized regions of the two salts have a co-saturation point in each phase diagram.The solubility of these two salts increases with increasing temperature,while in the crystalline region D-?-?-tartaric acid-R-?+?-phenethylamine is greater than D-?-?-tartaric acid-S-?-?-phenethylamine.In this paper,the thermodynamic model——Wilson model and NRTL model are selected to calcute the ternary systems.The programming is done with Matlab software.The optimal parameters are obtained by calculating the errors between the experimental value and the calculated value.By calculating the relative deviation and root mean square deviation,it can be seen that the RMSD of the Wilson model is1.07×10-3and 6.2×10-3?7.64×10-4and 6.18×10-4?5.65×10-4and 3.97×10-4?4.98×10-44 and 3.02×10-44 at four different temperatures.The RMSD of NRTL model is 0.0085 and 0.0077?0.0069 and 0.0054?0.007 and 0.0056?0.0076 and 0.0044 at each temperature.As for the Wilson model,the error is smaller than the NRTL model.It is not difficult to conclude that the results of the Wilson model experimental regression are very ideal,and the regression results are in good agreement with the experimental values at four different temperatures.In this paper,the separation of D-?-?-tartaric acid-S-?-?-phenylethylamine and D-?-?-tartaric acid-R-?+?-phenylethylamine was calculated by drawing two phase diagrams at different temperatures.Two different routes were provided,and the first and stable cycles in the separation process of the two routes were analyzed and compared by two methods.In the first route cycle,the first cycle is L?A?B?C?D,and the stable cycle is?D?E?F?B?C?D?E?F?B?C?n.The first cycle and stable cycle yields of D-?-?-tartaric acid-S-?-?-phenethylamine and D-?-?-tartaric acid-R-?+?-phenethylamine were calculated to be 80.91%and 70.05%,respectively.,78.05%and 70.06%,the first cycle and stable cycle of D-?-?-tartaric acid-R-?+?-phenylethylamine and D-?-?-tartaric acid-S-?-?-phenylethylamine were calculated by the ratio method.The yields are 80.91%and 70.04%,78.58%and70.14%,respectively;during the second route,the first cycle of separating the solid mixture into pure is L?A?B?C?D?E?F,and The stable cycle is?F?G?H?I?J?K?M?F?G?H?I?J?K?M?n,and D-?-?-tartaric acid-R-is calculated graphically during the cycle.The first cycle and stable cycle yields of?+?-phenylethylamine and D-?-?-tartaric acid-S-?-?-phenethylamine were 80.88%and70.03%,78.52%and 70.03%,respectively,and the ratio method was used to calculate D.The first cycle and stable cycle yields of D-?-?-tartaric acid-S-?-?-phenethylamine and D-?-?-tartaric acid-R-?+?-phenethylamine were 80.45%and 70.05%,90.29%and70.05%,respectively.In the two loop routes,it can be known from the analysis in the calculation process that the ratio method is better than the graph method,and the calculation method with the ratio method is higher.At the same time,it is not difficult to find out from the analysis in the loop process.The first loop path has passed.Two crystals,but the yield of the mixed salt is lower than the second circulation route;and the second circulation path is three crystals,and the yield is higher than the first circulation route.In view of the priority given to the yield during the production process,a second circulation route can be chosen. |
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