Will using silica/alumina as a dessicant change my pH?

Hash and Stuff Pre/Post-Processing
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I’m in the process of drying some of my solvents and catalysts. Just wondering if anyone has any experience using silica or alumina as a dessicant?

I know that the acidic catalysts I’m using will eat up the zeolite, so I was curious if another dessicant would do a better job? I was worried that since the alumina is generally activated with an acid, it could mess with the pH and potentially cause unwanted isomerization.

Would me drying my acid over alumina cause isomerization? Or would it be a very minor problem? Should I use chromatography grade stuff? Or can I just buy some of those consumer beads for silica?

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I could be way off base here but I think the alumina might neutralize the acid in some part (isn’t it generally basic?). How about epsom salt?

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I think that would work for dehydrating the alcohol, but maybe not the acid? I read that aqueous hcl reacts with the magnesium sulfate, I don’t know enough chemistry to know if the same principal would apply to Lewis acids.

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I suppose that would make sense lol, HCl and MgSO4 probably like to make sulfuric and MgCl2…

Then again I think sulfuric forms a solid hydrate so maybe that wouldn’t be the end of the world, just might mess with your stoichiometry.

Reminder: I’m not a chemist lol, someone keep this man from listening to my uneducated ramblings lol

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Maybe some kind of organic hulls or something? Rice maybe? Or tapioca?

@MagisterChemist any ideas?

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I mean how dry do you need? Like my reaction will catch fire if it isn’t? Anhydrous HCl is available and you can dry the rest of the reagents using zeolites.

I think epsom or CaCl2 would probably be worth trying without any of the expensive stuff and see if you can remove the water mass without a problem

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I’m just going for trace water, but dryer the better

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Is HCl the acid? Everything I’m reading says if you dry HCl, you’re working with a gas

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You really need to give specifics for an answer to this. If you don’t want to share it, message me

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Edit: Disregard. Wrong info.

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Alumina (Al2O3) is not aluminum (Al)…

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My mistake, I know aluminum oxide is not aluminum. I pulled the wrong equation and didn’t realize. Thanks for clarifying.

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When using Epsom for drying down chemicals one must first dehydrate the Epsom to achieve an anhydrous state. That’s the extent of my knowledge of Epsom and I make no claims about its fitness for your particular purpose

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This is the case for most drying agents. My method for deciding if something will work as a drying agent is see if it forms both a solid hydrate and anhydrous form. The more hydroscopic it is the better it works. Then I usually (and very scientifically) Google around to see if it reacts with my solvent or reagents lol.

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I’m not sure which catalyst you’re trying to dry but I’m assuming it’s ethereal HCL that you’ve made with a gas generator. If so, you can still use activated Zeolite to dry the solution as long as it’s a relatively quick dry time (less than 12 hours, someone on here reported that longer soak times broke down their beads) and as long as you’ve diluted it to a 1M or 2M concentration.

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Not really sure. Deciding between a Lewis acid or Dilute HCL pending on what kind of drying can be done