Sciencemadness Discussion Board

Disposal of sulfuric drain opener

ManyInterests - 6-1-2021 at 20:26

I am asking this just to be completely and absolutely sure. But to dispose of sulfuric acid based drain opener, after diluting it in large quantities of water (with at least a 10:1 ratio of water to acid) and reducing it with carbonate (I used homemade sodium carbonate, around 500 grams of it). and once it ceases to fizz after more carbonate/bicarbonate is added, it can be just flushed down the toilet, correct?

Yes I am a noob, but I like to be ultra safe about everything I do.

Sulaiman - 6-1-2021 at 21:36

The purpose of drain opener is to open drains,
so you can assume that it is ok to put in drains :P

You have done better, you neutralised the acid,
so it can definitely be flushed down a drain or toilet.

aromaticfanatic - 6-1-2021 at 22:01

Yes you did it correctly. If you don't want to do what seems like countless hours of neutralizing and trying to avoid loads of foaming, you can use pH paper and sodium hydroxide drain cleaner until neutral or slightly basic. Beware that a lot of heat is released through the entire process (diluting sulfuric acid, making sodium hydroxide solutions, and neutralizing the two all create a lot of heat, I have actually gotten a little bit of a quick boil to happen when I added a small amount of sulfuric acid to hot sodium hydroxide solution. Instantly boiled in the local area that I added the acid. I added a little knowing this point was coming ;) ) so depending on your scale you'll need to use ice baths or just use time to let everything cool down.

Also the neutral point comes QUICK so my recommendation is to use NaOH to get the pH to around 2-5 and then use baking soda for the rest of the neutralization. Baking soda is much less aggressive on pH.

ManyInterests - 6-1-2021 at 23:44

Thanks. I live in a small apartment, so things like fumes and other stuff are particularly concerning to me. I have a balcony, but I am not super comfortable putting too much stuff out there because it might alarm neighbors who have no idea what I am doing. I am not sure how well ventilated my apartment would be even if I opened all windows and the door to my balcony.

that's also why people who say 'boil this with acid in it' even when I get my first heating pad will need to be done correctly to make sure I can route fumes outside. The last thing I want is to have fumes that I cannot easily get out of my apartment.

Tsjerk - 6-1-2021 at 23:55

I wouldn't neutralize it, just poor it down the drain, it will get neutralized on its way to the water treatment plant. Unless you have a septic tank off course.

pip - 3-2-2021 at 15:22

Definitely neutralize it if you can, it eats iron pipes and if you have very old iron pipes it can be a problem after repeated disposal.

I worked in an apartment complex that if you just looked at the old cast drain pipes they sprung a leak.

Fyndium - 3-2-2021 at 16:51

Drain it, and run a lot of water after it. If the pipes are so crappy they let on from drain opener, it's only a good kick-start for renovation. In my country it is even illegal to have such bad pipes as such housing units are rendered unsuitable for human occupation.

Safety is a top priority, and always study ahead any reaction and interactions to avoid producing any unwanted fumes and stuff. Easiest way to control smells and vapors is to get a fume hood, you can vent it through the kitchen exhaust fan that goes to the roof directly if necessary and this creates a negative pressure. I also live primarily in a rather small apartment and I have taken very wide measures to eliminate the possibility of any odors, vapors or contamination. I actually make my entire apartment a negative pressure space with a little trick so air flows inwards from the hallway, so zero odors will ever be smelled by any neighbors. Good venting also keeps odors and vapor concentrations low, so risk of any flame is minimized. When working with extra volatile stuff, extra precautions should be taken, for example I only handle ether in closed vessels, through trap and vent the tube directly to the duct line. Actually, I only use jointed glassware for everything I do if it's stronger than brine or bicarb, basically.

Venting through your toilet water trap is also an option, last time I had to make a reaction that produced NO2 I vented it there with zero issues.

ChemTalk - 14-2-2021 at 17:05

Remember to dilute it before you neutralize it. Reacting concentrated acid with sodium bicarbonate will expel some of the acid into the air. Not pleasant if you are in the area!

ManyInterests - 27-2-2021 at 17:44


Remember to dilute it before you neutralize it. Reacting concentrated acid with sodium bicarbonate will expel some of the acid into the air. Not pleasant if you are in the area!

I did do my experiment a bit, and it didn't produce as much fumes for me to be bothered or even notice. Now granted I used very small quantities of acid (60 ml or so) so I figure this isn't enough to cause problems.

I have been looking into how ventilated my apartment is. I did make some smoke (potassium nitrate/sugar test! That stuff I made is pure!) with all my windows and balcony door open just to get an idea of how it will circulate. It seems like that if I have all the doors open (except my apartment door) most will circulate around a specific area before leaving out a window.

But some will end up getting heading towards my bathroom. I turned on the fans from my stove and bathroom and it seemed to handle it quite well. But that was not a dangerous fume.

I have been looking into fume hood construction and it seems fairly basic. Some fume hoods seem really simple and quick for my needs and are easy to take down when I don't need them to save on space.

That's one example. I'll be looking into more to see what else can be done before I commit to a project.

Amos - 27-2-2021 at 18:20

I wouldn't even bother neutralizing; just dilute it in maybe 100 parts water and pour it down the sink. I would imagine the increased salinity you're adding to the water by neutralizing it is actually harder to correct in water treatment than low pH is, anyway.

Sulaiman - 28-2-2021 at 02:27

Wind can come from different directions,
you may find that quite a powerful fan is needed to guarantee correct airflow direction
Quote: Originally posted by ManyInterests  
... I have been looking into how ventilated my apartment is.

Tsjerk - 28-2-2021 at 02:34

I wouldn't even bother diluting the acid, I would do an in-line cleaning of my drain with the concentrated acid.