Recycling of NH4Cl in the synthesizing process of analcime to ammonioleucite by separating NH4Cl-NaCl mixed solution

• Published in: Chemical papers Vol. 76; no. 9; pp. 5943 - 5954
• Main Authors: Li, Yunfei, Tang, Yong, Liu, Meitang, Hu, Haisheng
• Format: Journal Article
• Language: English
• Published: Warsaw Versita 01.09.2022; Springer Nature B.V
• Subjects: Ammonium chloride; Biochemistry; Biotechnology; Chemistry; Chemistry and Materials Science; Chemistry/Food Science; Crystallization; Evaporative cooling; Industrial Chemistry/Chemical Engineering; Materials Science; Medicinal Chemistry; Original Paper; Recycling; Separation; Sodium chloride; Ammonium chloride; Phase diagrams; Separate; Recycling; Ammonioleucite
• ISSN: 0366-6352; 1336-9075; 2585-7290
• DOI: 10.1007/s11696-022-02300-2

During the transformation of analcime to ammonioleucite, the mol ratio of NH 4 + : Na + in the NH 4 Cl-NaCl mixed solution will seriously affect the conversion rate of ammonioleucite. How to separate the mixed solution and recover NH 4 Cl becomes the critical problem for the industrialization of this process. In this paper, the critical separation point of the mixed solution was testified to 8:2 (mol concentration ratio of NH 4 + : Na + ). The isothermal evaporation equilibrium method was used to explore the dissolution equilibrium law of NH 4 Cl-NaCl mixed solution at 343 K, 353 K, and 363 K. The separation of the mixed solution under the conditions of 343 K, 353 K, and 363 K were studied by using the three-time evaporating-cooling crystallization process. At 353 K, the recycling rate of NH 4 Cl can reach 91.12%. This work provides a foundation for the industrial feasibility of synthetic ammonioleucite from analcime.