Polyethylene glycol regulated carnallite decomposition-crystallization: Experimental and theoretical analysis
Currently, the “crystallization-flotation” process is widely used for the industrial production of KCl. However, the significant aggregation of KCl and NaCl in the decomposition-crystallization stage of carnallite leads to inefficient separation of the two particles in the flotation stage, which restricts the production of high-grade KCl. In this study, environmentally friendly polyethylene glycol (PEG) was used to regulate the decomposition-crystallization of carnallite for the first time, and the high-grade KCl was successfully prepared by reducing the degree of crystal aggregation. The crystals were characterized by SEM-EDS, FT-IR, XRD and AFM, and it was found that PEG which average Mn 800 (PEG 800) could adsorb on the crystal surface and effectively disperse NaCl and KCl. It was also found that there are two mechanisms by which PEG 800 achieves dispersion. On the one hand, PEG 800 micelles contain polyoxyethylene chains with large steric repulsion, which can prevent the adhesion of particles. On the other hand, PEG 800 can weaken the electric potential on the surface of KCl and NaCl and reduce the electrostatic interaction force between the particles. Finally, the behavior of Na, K, and Cl before and after the addition was simulated by molecular dynamics, and molecular dynamics calculations showed that PEG 800 could weaken the effect of NaCl on KCl.
危险品化学品经营许可证（带存储）