Need suggestion of commercial chemical to clean shower stall

[yungman]

Hi
I have a hard time cleaning the deposit on the floor of the shower stall made of Dupont Corian. I believe it's a combination of hard water ( known to have hard water), soap scum. I tried scrubbing with all different household stuffs including Soft Scrub, Tilex and other common stuffs with breach. I tried vinegar to see whether it's calcium deposit. I tried alcohol, acetone, lighter fluid as a whole spectrum from polar to non polar compound. None of the alcohol, acetone and lighter fluid work at all.

Vinegar did not work. Only thing that worked really slow and only at the beginning is Soft Scrub. but now it does not even work anymore.

I know this is not supposed to be in chemistry forum. I was a chem major before, I tried everything I can get. Of cause I can't get HCl or H₂ SO₄ etc.! I am running out of ideas. Any advice.

Thanks

 

[Bystander]

deposit on the floor of the shower stall made of Dupont Corian.

Is it colored? Iron stains can be stubborn. I've had fair luck with citric acid (lemon juice) as far as complexing and lifting iron stains.

 

[yungman]

Is it colored? Iron stains can be stubborn. I've had fair luck with citric acid (lemon juice) as far as complexing and lifting iron stains.

Thanks for the response. It is grey and slightly brownish. Yes, the water here is slightly brown, I always think it's mud!

 

[berkeman]

I have been impressed with the cleaning abilities of this product -- maybe give it a try (it works great in my shower/tub for removing stains, etc.):

http://c4.soap.com/images/products/p/pg/pg-3168_1z.jpg

 

[yungman]

Hi, I tried Magic Eraser, Easy-Off oven cleaner, nothing worked. Finally I happened to see a drip coffee cleaner that contain sulfuric acid. I got a bottle, I pour that over the stain, let it sit for an hour, then I add Soft Scrub and scrub it. Let it sit for another hour and scrub again before rinsing it away. After 3 time, I definitely see big improvement.

So it is definitely lime build up that acid can loosen it. My question is what acid should I get? I saw on Amazon selling 0.12N sulfuric acid. Is that too strong? It's been 40 years since I touch chemistry even though my degree was in chemistry...never work a day of my life in chemistry. I don't remember what is 0.12N for concentration anymore!

Is HCl or HNO₃ any better?

 

[Borek]

0.12N sulfuric acid is quite diluted, around 0.6%.

But if sulfuric acid works, hydrochloric should work even better. I would not use nitric acid, quite unlikely you need additional oxidizing power.

Don't mix different cleaner until you are sure you know what you are doing - its asking for troubles, as they are often based on different, incompatible chemicals. You can start a fire or produce toxic fumes.

 

[Bystander]

Sounds like gypsum rather than lime. People refer to both crud buildups as lime. Ice water, or just crushed ice. It'll be slow, and take several treatments.

 

[mp3car]

Have you tried original CLR (sometimes C L R, it stands for it's cleaning purpose, "Calcium Lime Rust)? It is a mixture of a bunch of different acids. I believe it's pH is pretty low, maybe 2-ish. I just looked up it's components a few days ago after I accidentally damaged a spot on my granite counters. I wasn't using it to clean the counters, but it was in a container sitting on the counter and it had a very small hole/leak and after sitting there for two days, an ounce or so had leaked out and flowed around the bottom of the container like a ring on wood table from a glass of chilled beverage. I now have an "etched" ring on the black granite! I don't think any "stain" remover intended to remove stains from granite will help me, since I am pretty sure it's not a stain, but it's etching or bleaching that has occurred. I am suspecting my only hope will be to intentionally apply a very small amount of a black or very dark gray stain of some kind... I have inquired to a granite importer and distributor, if they don't get back to me, I will probably make a post on the chemistry forum...

Also, I have talked with folks at dupont can be extremely helpful with their products. They make a lot of industrial chemicals, and since they make corian, they may be able to help you out! The hardest part is getting someone who is actually very technically knowledgeable, not just a customer service rep who goes from their scripted info...

Anyhow, below is the link to the product and MSDS, and for the chem folks, here the active components... I don't know what country you're in, but in the US, it's sold at many big-box stores like Lowe's, Home Depot, Walmart, etc... I generally keep a 1 gallon bottle on hand, I have hard water and it works great to clean all the bathroom and kitchen fixtures a few times per year (showerheads and kitchen sink spray head specifically). When I looked it up a few days ago, I thought I read it had a few more acids in it as well, like glycolic, citric and sulfamic, but i looked for the MSDS just now and it only shows gluconic and lactic. Maybe it is a different product made by them (Jelmar). And if you're a chem major, i don't need to tell you don't be fooled by the harmless sounding citric and lactic acids... We're not talking orange juice or sour cream! ;)

One last thing, have you tried "mechanically" getting it off? My previous house had corian, but now just have granite, but I am wondering if a very sharp (new) razor blade scraper can be used without damaging the surface? I know I use it on my granite sometimes, but that's obviously a lot different than corian.

Component: CAS#: OSHA Hazzard: % by weight.
1. Lactic Acid: 79-33-4: YES: 12.00-18.00
2. Gluconic Acid: 526-95-4: YES: 2.50-3.75
3. Lauramine Oxide: 1643-20-5: YES: 1.50-3.25

http://www.jelmar.com/CLRbasic.htm
MSDS http://www.jelmar.com/msds/2014/CLR_SDS_520514.pdf

sorry for being so long winded, have had too much caffeine today! :)

 

[yungman]

0.12N sulfuric acid is quite diluted, around 0.6%.

But if sulfuric acid works, hydrochloric should work even better. I would not use nitric acid, quite unlikely you need additional oxidizing power.

Don't mix different cleaner until you are sure you know what you are doing - its asking for troubles, as they are often based on different, incompatible chemicals. You can start a fire or produce toxic fumes.

Thanks, I'll look into HCl in the future. So far I am happy with the the drip coffee cleaner scrub together with Soft Scrum. The stain is almost gone, maybe two more times. No smell at all other than the Soft Scrub smell.

 

[yungman]

Have you tried original CLR (sometimes C L R, it stands for it's cleaning purpose, "Calcium Lime Rust)?

Component: CAS#: OSHA Hazzard: % by weight.
1. Lactic Acid: 79-33-4: YES: 12.00-18.00
2. Gluconic Acid: 526-95-4: YES: 2.50-3.75
3. Lauramine Oxide: 1643-20-5: YES: 1.50-3.25

http://www.jelmar.com/CLRbasic.htm
MSDS http://www.jelmar.com/msds/2014/CLR_SDS_520514.pdf

sorry for being so long winded, have had too much caffeine today! :)

Thanks, I tried CLR, it did not work. In fact CLR did not work on anything I want to clear for whatever reason!

I'll look into your other suggestion when I am ready to clean the clear shower door. That's another stubborn problem.

Thanks.

 

[phinds]

I use "Lime Away" for my shower stalls and it works terrifically well, but the damned stuff will ream out your nostrils so I only do a small area at a time.

 

[SteamKing]

I use "Lime Away" for my shower stalls and it works terrifically well, but the damned stuff will ream out your nostrils so I only do a small area at a time.

You should use these products in a well ventilated room or wear breathing protection. You don't want your lungs eaten away by the fumes.