can i de-chlorinate tap water with h2o2?

[heady blunts]

just like the title says: can i de-chlorinate my tap water with h2o2? i figured if it works it would be pretty instant.

the reason i'm asking is today i woke up and found my rez nearly empty, but i hadn't filled a container with tap water the night before like i normally would to allow the chlorine to evaporate. so i was thinking it'd be helpful to have a super quick emergency method to de-chlorinate tap water.

ps- for now i've got a little waterfall going with my water pump to speed things up.

 

[Big D]

I don't know about the H2O2... never heard that. But you can boil your water for 15-20 mins and let cool.

 

[jaykush]

you can use vitamin c to de-chlorinate tap water. you only need a tiny bit. plants also like its subtle qualities in low doses.

 

[montehierba]

Chrorine vaporizes over night budd.

 

[heady blunts]

i'm lookin for quick ways like less than 10 minutes.

jay- how fast does the vitamin c work? what amount do you put per gal?

 

[C21H30O2]

i use a single tab, 500 mg i think, for over 30 gallons. never really measured b4 though.

 

[dmt]

yes you can, 1.6ml/litre (35% h202), d

 

[jaykush]

jay- how fast does the vitamin c work? what amount do you put per gal?

its pretty fast, i dont have a chemical analysis kit or anything but from what i read its rather instant as its a chemical reaction that doesn't get rid of the chlorine and chloramines but rather make them inert by some chemical process.

when i did use the vitamin c for this purpose long ago, i still didnt measure, how much water are you talking about?

 

[Microbeman]

From two different colleagues:

1/ ascorbic acid for chloramines or chlorine; 3 grams in 100 gallons will
treat up to 3PPM.

2/ I found your chlorine test interesting and decided to do the same to
put my arguement that reducing sugars in the molasses would handle the
chlorine and chloramine.

Using a similar test strip that tests for both free and total
chlorine, I found my city water to have 0.5ppm free and 1.5 ppm of
free and total chlorine,respectively. Testing 1 gal and 5 gal of city
water, I added 1/4 teaspoon of molasses to each. The reaction was not
instantaneous but the kinetics were faster than I would have guessed.
The one gallon reaction showed no dectable chlorine of either type
withing 3 minutes. At 5 gallons, I obtained the same result within 20
minutes.

Chlorine levels are regulated a 4 ppm maximum
4 ppm = 4mg/l
Chloramine concentrations are expressed as chlorine equivalents, so one uses the molecular weight of chlorine for calculations.
One molecule of reducing sugar will react with one molecule of chlorine.
Therefore, on a weight basis, one needs 4mg/l *(the molecular weight of the reducing sugar/the molecular weight of chlorine)/ (the decimal fraction of reducing sugar in your molasses)
I’ve seen numbers ranging from 15% to 50% for the percent reducing sugar in molasses
The reducing sugars are going to be a mixture of mono and disaccharides. Molecular weights = 180 and 342, respectively
Chlorine molecular weight =70
Therefore, worst case, one needs 4*(342/70)/.15 =130mg/L molasses
I saw a recipe by Elaine that calls for 1 oz molasses in 5 gallons. That’s 1 part in 640 or 1563 ppm .
So, worse case you have a 12 fold excess.


Run these same numbers for pure glucose (a reducing monosaccharide) and you end up needing 10ppm glucose. When i need dilution water for spraying, I use a 20-30 ppm glucose and let it sit overnight.


I continue to be perplexed by the amount of hand wringing that
goes on over chlorine and chloramine. These both function as
oxidizing agents and, as such, are destroyed by reducing agents.

Cane molasses runs at 15-20% reducing sugar.
Regulations allow a maximum of 4ppm chlorine, expressed as Cl2.
Allowing for the molecular weight difference between Cl2 the
reducing sugars in molasses, you would need 10ppm reducing sugar to
react with the chlorine.
At 15% reducing sugar, you need 66ppm molasses.

I put my molasses in first, give it some time to react and don't
worry.

Also a small amount of soil or compost will instantly neutralize chlorine or chloramines. I have found aerating or sitting overnight to have varying results...sometimes not effective.

 

[Microbeman]

h202 like chlorine is an oxidizer (oxidant). There is not much hope that it would neutralize chlorine. They both kill microbes.

 

[heady blunts]

well that is fast enough for me. i'll just add my molasses first and wait at least 5 minutes.

 

[Microbeman]

To the PMer just put molasses or a bit of organic matter of some kind in your water container and let it sit for half an hour, then use it.

 

[heady blunts]

oh wait. that is useful to know for my compost teas but originally i wanted to de-chlorinate water for my blumat reservoir, and i shouldn't put any molasses in there.

does the vitamin c dissolve? or do the granules hang around?

 

[C21H30O2]

i break mine up into a powder... think coke, then slowly and evenly pour into the water

 

[PrivateAero]

Coke is liquid... Awesome info, never thought of adding something to the water to dechlorinate it. I'll definitely be using this info, thanks everyone.

 

[C21H30O2]

coke is a powder to some and a liquid to others.

 

[smoketrichs]

get some de-chlor from the pet store for aquariums. couple drops per gallon.