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Specialty Chemistry Forums => Citizen Chemist => Topic started by: mgholami13 on February 28, 2015, 12:21:56 PM

Title: Gelling Agents
Post by: mgholami13 on February 28, 2015, 12:21:56 PM
Hi dear all,

I have a question about gelling agents. Does anybody have any information about gelling agents that are used for acids?
Title: Re: Gelling Agents
Post by: billnotgatez on February 28, 2015, 01:05:26 PM
Since you question is general it might be difficult to answer in a few short sentences.
If you read the forum rules you might have made you question more precise as suggested by the rules.
Click on the link near the top center of the forum page.
Forum Rules: Read This Before Posting.
Also, we only post a given question once on the forum.
That is rule as well

My first suggestion is to use GOOGLE (google.com) and search on
gelling agents for acids
I did and got lots of links
Once you find something that might fit the question, you can bring it back here if you need more guidance.
That will make your question more precise.
Title: Re: Gelling Agents
Post by: mgholami13 on February 28, 2015, 04:06:29 PM
Since you question is general it might be difficult to answer in a few short sentences.
If you read the forum rules you might have made you question more precise as suggested by the rules.
Click on the link near the top center of the forum page.
Forum Rules: Read This Before Posting.
Also, we only post a given question once on the forum.
That is rule as well

My first suggestion is to use GOOGLE (google.com) and search on
gelling agents for acids
I did and got lots of links
Once you find something that might fit the question, you can bring it back here if you need more guidance.
That will make your question more precise.

More precise, does anybody know any specific gelling agent for chromic and nitric acid?
Title: Re: Gelling Agents
Post by: Arkcon on February 28, 2015, 05:02:59 PM
Sorry, but I don't think so.  We get this question often on this board, and no one ever has a good answer.  I know some sort of gelling agent is used to make naval jelly -- that's phosphoric acid in what I assume is some sort of organic gel, or maybe polysiloxanes is better.   But phosphoric acid is a weak acid.  People who want to gel con. sulfuric, or oxidizing acids may simply be out of luck.  There's also hydrated silica gels, but once you've added a very hydrated silica gel to concentrated sulfuric ... you don't have concentrated sulfuric anymore.
Title: Re: Gelling Agents
Post by: Borek on February 28, 2015, 06:13:28 PM
I believe there are gelling agents used in acid batteries, so they should be able to survive concentrated sulfuric acid.
Title: Re: Gelling Agents
Post by: mgholami13 on March 01, 2015, 09:41:46 AM
I believe there are gelling agents used in acid batteries, so they should be able to survive concentrated sulfuric acid.

Thanks Borek.
Do you have any idea about MSDS of those gelling agents?
Title: Re: Gelling Agents
Post by: Zyklonb on March 06, 2015, 12:36:20 PM
US Patent 4687718 A http://www.google.com/patents/US4687718 (http://www.google.com/patents/US4687718)
Silicon dioxide works well as a gelling agent. It doesn't react with either nitric acid or sulfuric, but I've only heard of it's use with the latter.
Quote
A lead acid battery in which each electrode is wrapped in a web of fiberglass and the gel electrolyte consists of a mixture of sulfuric acid and phosphoric acid and silicon dioxide as the gelling agent.
It might also work with chromic acid, but I couldn't find any info on this. What oxidation state of chromium. I sometimes  use hexavalent chromic acid to clean carbon stains from glassware. Be very careful with this stuff, it's a possible carcinogen and its very toxic. Not to mention the chemical burns...
Title: Re: Gelling Agents
Post by: mgholami13 on March 09, 2015, 10:54:36 AM
US Patent 4687718 A http://www.google.com/patents/US4687718 (http://www.google.com/patents/US4687718)
Silicon dioxide works well as a gelling agent. It doesn't react with either nitric acid or sulfuric, but I've only heard of it's use with the latter.
Quote
A lead acid battery in which each electrode is wrapped in a web of fiberglass and the gel electrolyte consists of a mixture of sulfuric acid and phosphoric acid and silicon dioxide as the gelling agent.
It might also work with chromic acid, but I couldn't find any info on this. What oxidation state of chromium. I sometimes  use hexavalent chromic acid to clean carbon stains from glassware. Be very careful with this stuff, it's a possible carcinogen and its very toxic. Not to mention the chemical burns...

Thanks Zyklonb for your information,

I tried both silicon dioxide and silica gel on the nitric acid but I got no gelling effect on that. Should be any special procedure for mixing them? If anyone knows please help.
Title: Re: Gelling Agents
Post by: billnotgatez on March 10, 2015, 01:20:20 AM
@mgholami13
What was the product you tried as far as silica source.
Just sand?
I think @Zyklonb may be on the right track
We sort of got gel with HCl and fumed silica
It was some time ago but that is what my memory says
I think we just blended it.