Caprolactam crystallization and purification
The modern crystallization purification techniques have the simple flow and continuous processes. The purification of the amide oil to caprolactam is achieved after pre-treatment (including dehydration, dehydrogenation, and deweighting) and crystallization. The amount of benzene used in the purification process is greatly reduced, and no solvent is used in the crystallization process. Safe and reliable, the process can greatly reduce the investment and the running cost. The product is caprolactam crystal with excellent quality, which is convenient for transportation. This stable product can endure long-term storage, enabling itself to fill the market gap of high-end nylon 6 raw materials in China. The technology can be combined according to the on-site requirements (such as starting materials can be amide oil, heavy residue, benzene steam residue, etc.) and can support the industrialization breakthrough of the caprolactam gas phase rearrangement ammonium sulfate-free technology.