Study on the Formation of Glycine by Hydantoin and Its Kinetics
Hangyu Zhao, Rong‐hua Yu, Hao Qiao, Cunli Liu
Abstract
The preparation of glycine by the hydantoin method is currently a relatively advanced process. The raw materials of this process are nontoxic, the operation process is simple and safe, the side reactions are few, and the yield of glycine is high. The core reaction of the hydantoin method is the hydrolysis of hydantoin. The hydrolysis is divided into two steps: first, hydantoin is hydrolyzed into hydantoin acid, and hydantoin acid is further hydrolyzed into glycine. At a temperature of 423.15 K, a molar ratio of sodium hydroxide to hydantoin of 1:3, and a total reaction time of 6 h, the conversion rate of hydantoin reached 100% and the yield of glycine reached 91%. At the same time, by calculating the hydrolysis kinetic parameters, the reaction was determined to be a first-order series reaction, and a kinetic model was established, which laid the foundation for the development of a green glycine process and a new reactor.