Research On Synthesis And Purification Of N, N-Dimethyl Glycine

The mainly preparation methods of N, N-dimethyl glycine are biological extraction and chemical synthesis. There are purification difficult issues in chemical synthesis which use chloroacetate and dimethylamine to react. For change the materials of reaction the N, N-dimethyl glycine was got directly in this article. The solvent crystallization and electrodialysis were used for purification research.Synthesis of using chloroacetate sodium and dimethylamine reaction can get a mixture of N, N-dimethyl glycine and sodium chloride. Inspected the reaction of temperature, reaction time and the ratio of the response to determine the best conditions, for which we determined the best conditions: ratio of the response 1:1.1, 3hour, 30℃. Inspected the solvent crystallization of the solvent type and volume on desalting effect, determined the volume of the best solvent ethanol(260mL-330mL)/mol. Using electrodialysis to research the desalting, inspected the voltage, flow rate, temperature, salt concentration, pH, which affect the electrodialysis, determined the best conditions were 35V, 5cm/s, 25g/L, and pH nearly to 5.4. Inspected the relationship between the content of chloride ion and the purification of N, N-dimethyl glycine, determined the purification of N, N-dimethyl glycine could get to 99% when the content of chloride ion was 0.02%.