Despite the exceptional fire-suppressant capabilities of ultrafine dry powder fire extinguishing agents, additional work is essential to improve their overall fire-extinguishing performance. In this investigation, we explored the utility of Fe 3+ loaded ZSM-5 zeolite in enhancing the firefighting capabilities of ultrafine dry powder fire extinguishing agents. The loading of transition metal ions Fe 3+ onto the ZSM-5 zeolite was achieved through the ion solution exchange method. Interestingly, the loading of Fe element on Fe/ZSM-5 zeolite displayed a pattern of initial increase followed by decrease as the ion exchange time lengthened. Furthermore, the loading of Fe element on Fe/ZSM-5 zeolite was found to be influenced positively by the initial molar concentration of Fe 3+ and pH levels. Impressively, under specific working conditions, the prepared Fe/ZSM-5 zeolite demonstrated a substantial Fe element loading of 5.82 %. Incorporation of ZSM-5 zeolite resulted in a 10.01 % enhancement in the fire-extinguishing efficiency of the ultrafine dry powder compared to undoped samples. Moreover, the incorporation of Fe/ZSM-5 zeolite has resulted in an enhancement of fire extinguishing efficiency by 20.45 % (S3), 24.20 % (S4), and 29.04 % (S5) in comparison to S1. These findings contribute to the understanding that the incorporation of Fe/ZSM-5 zeolite significantly enhances the fire extinguishing performance of ultrafine dry powder fire extinguishing agents, with extinguishing efficiency improving with increased Fe element loading.
Isotopic separation is of paramount importance for producing high-purity heavy hydrogen, yet the process remains hugely challenging. Here, we report on an Fe/ZSM-5 zeolite that was able to efficiently separate deuterium from protium via chemical quantum sieving. Structural data showed that four types of Fe species were present in Fe/ZSM-5 and oligomeric Fe–O clusters in the zeolite pores were correlated directly with gas selectivity. Gas adsorption revealed that Fe–O species served as the main adsorption sites and interacted with D 2 more strongly than with H 2 . D 2 /H 2 separation was exemplified using thermal desorption spectroscopy. D 2 /H 2 selectivity increased with Fe loading in Fe/ZSM-5 and a selectivity of 32.1 was obtained with an optimal loading of 7 wt%. The shift of desorption temperature supports the chemical affinity-based quantum sieving of D 2 over H 2 . This study demonstrates an effective strategy for enhancing D 2 /H 2 separation and the high selectivity means that Fe/ZSM-5 has strong potential in hydrogen isotope separation.
危险品化学品经营许可证（带存储）