Effect of Synthesis Process on ZSM-5 Morphology from Non-ferrous Metal Tailings

Using the non-ferrous comprehensive tailings from Guangxi Province of China as raw materials, by the mixed guiding method of ethanol and ethylene glycol, a high-quality product with a short b-axis hexagonal prism morphology and a relative crystallinity of 100.7% was hydrothermally synthesized. A variety of physicochemical characterization methods, such as XRD, SEM, and ICP, have been used to investigate the effects of precursor solution composition on product quality. The results showed that ethanol partially replaced most of tetrapropyl ammonium bromide. Compared with the traditional method of using a large amount of organic amine template to synthesize ZSM-5, this method in the synthesis system using tailings slag as raw materials had a better relative crystallinity (99.8%) of the product, but the shape of the product was spheroidal. When the n(SiO₂): n(ethanediol) molar ratio of ethylene glycol added in the synthesis system was 0.09, a high-quality product with a more perfect short b-axis hexagonal prism morphology and high relative crystallinity (100.7%) can be obtained using non-ferrous metal comprehensive tailings as raw materials. In addition, this process was applied to tin tailings and tungsten tailings, and ZSM-5 molecular sieves with regular morphology were successfully obtained.