Controllable growth of defect-free zeolite protective layer on the surface of Pd membrane for chemical stability enhancement

摘要: Abstract Pd membranes play a critical role in hydrogen purification due to excellent permeability and selectivity. However, the poor chemical stability of when exposed inclusion gases or organic reactants severely restricts their commercial applications. Herein, novel strategy is developed synthesize thin compact zeolite layer on surface membrane which acts as an “armor” protect it from being damaged by poisoning species. The results show that was NaA type defect-free using Si/Al ratio 7.5 silica sol Si source after two-step hydrothermal synthesis. variations H 2 permeance monitored zeolite-Pd composite are 40% (ethanol/H O) 0.2% tetrahydrofuran (THF)/10% N atmosphere. Reactions between ethanol water active sites undetected, indicating completely out contact with presence protective layer. Especially, compared pure membrane, almost 80% decline constrained at 350 °C W/E = 6. Moreover, obviously enhances suppressing THF cracking coverage.