Several questions about molecular sieves
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1. How to dissolve EDTA-4H? If it is dissolved using sodium hydroxide, isn’t there then much difference between it and EDTA-2Na? I’ve read in the literature that it can form good complexes with non-skeletal aluminum, but when I tried using EDTA-2Na, there was almost no effect. Additionally, even dissolving EDTA in boiling water didn’t help to dissolve it. I’m not sure what the problem is 2. Besides non-skeletal aluminum, what other major factors influence the hydrophobicity of molecular sieves? 3. Is graft modification to improve the hydrophobicity of molecular sieves practically feasible for industrial application? What are the advantages and disadvantages of this method? 4. Do metal ions have a significant impact on the hydrophobicity of molecular sieves? (3A, 4A, 5A differ in terms of the metal ions they contain; as a result, their water absorption capacities vary. Is it simply because the diameters of the metal cations differ that the pore sizes of the molecular sieves change, which in turn leads to differences in water absorption?) If we know the reason why it is hydrophilic, we can use that property to apply it inversely to hydrophobic molecular sieves.) 5. Is the aluminum removal using phosphoric acid-modified molecular sieves effective? Why, after doing it several times, does the water absorption test show that only part of the aluminum has been removed? Is it because the amount of acid isn’t enough? Or is it some other reason?
I think you’re a student; if so, definitely don’t consider going into industrialization! It’s still more important to publish articles to graduate; thinking about industrialization is just harming oneself! 、
I think you’re a student; if so, definitely don’t consider going into industrialization! It’s still more important to publish articles to graduate; thinking about industrialization is just harming oneself!
The hydrophobicity and hydrophilicity of molecular sieves are related not only to the silica-to-alumina ratio in the framework but also to structural defects. Particle size also indirectly affects structural defects; therefore, it influences the hydrophobicity and hydrophilicity of molecular sieves as well.