Dechlorinating Water

[Dietitian]

If I want to lower my chlorine level quickly, how much hydrogen peroxide should I use per free chlorine ppm?

Would it be possible to add H202 to a gallon of tap water (for drinking) to reduce the chlorine and improve the taste? Would the chlorine be reduced to chloramines? Would the peroxide attack the chloramines as well?

[bart6453]

If I want to lower my chlorine level quickly, how much hydrogen peroxide should I use per free chlorine ppm?

Would it be possible to add H202 to a gallon of tap water (for drinking) to reduce the chlorine and improve the taste? Would the chlorine be reduced to chloramines? Would the peroxide attack the chloramines as well?

1.025 ounces of 3% hydrogen peroxide should neutralize 1ppm FC in 500 gallons of SPA water.

Why would you want to add something more to water you drink???

Really????

Don't you think the trained professionals at your local water treatment plant are the best suited to decide how to handle your drinking water?

[chem geek]

Also note that you might not have chlorine in your water, but rather monochloramine. Some water districts have moved to using monochloramine instead of chlorine. I do not believe that hydrogen peroxide will be effective at removing monochloramine and even if it did, it would likely result in ammonia.

Unless the chlorine or monochloramine level is rather high in the water, it is unlikely that this is the source of what you are tasting. If you want better tasting water, the easiest approach is to use a water filter as most use activated carbon to remove a variety of compounds, some of which are the cause of poor tasting water. At home, we have a Multi-Pure MP750SB under the sink water filter (with faucet at the sink) and in the master bath and around the house we use a Pitcher with a Brita water filter. My wife is very sensitive so notices the difference.

Though the capacities of the filters are approximately correct when filtering chlorine, the filters can last much, much longer when filtering monochloramine since the filter "activated carbon" does not get completely used up when breaking down monochloramine. You can test the water with a chlorine test that also tests for Combined Chlorine (even a simple OTO test, if you wait long enough) to see that the filter is still working.

[Dietitian]

1.025 ounces of 3% hydrogen peroxide should neutralize 1ppm FC in 500 gallons of SPA water.

Why would you want to add something more to water you drink???

Really????

Don't you think the trained professionals at your local water treatment plant are the best suited to decide how to handle your drinking water?

The professionals are pretty good at providing water that is safe to drink, but it tastes like chlorine. I would like to safely and quickly remove the chlorine from my water to improve taste.

Currently my water arrives with about 3ppm FC and 2ppm combined chlorine, PH 9, and 600 ppm TDS. The water routinely falls out of spec as well. This summer the water contained unsafe ammonia levels for three months. We were notified this winter of the error.

The main problem is the chlorine smell. It can be removed with a Brita filter, but if a drop of H202 can safely remove the chlorine, that seems easier and faster.

[chem geek]

Currently my water arrives with about 3ppm FC and 2ppm combined chlorine, PH 9, and 600 ppm TDS. The water routinely falls out of spec as well. This summer the water contained unsafe ammonia levels for three months. We were notified this winter of the error.

Yikes! No wonder you taste the chlorine. Our water used to have < 1 ppm FC by the time it got to our house and now with monochloramine it's 1.2 ppm, but still hard to taste the chlorine or monochloramine itself. In our situation, the "bad" taste is mostly from other things in the water.

The combination of 3 ppm FC with 2 ppm CC is a bit of a concern. It would seem that the CC is persistent since if it started out as ammonia it should have been oxidized by the time it got to your house. So it may be some sort of organic that is slower to oxidize.

I don't know if hydrogen peroxide will be a strong enough reducing agent to dechlorinate the CC. It will certainly be able to remove the FC. You could certainly try it to see how it works by measuring the FC and CC after treatment. Add enough treating the CC as if it were FC in terms of calculating the amount of hydrogen peroxide needed. So to get rid of 5 ppm FC+CC in one gallon, it would take about one drop of 3% hydrogen peroxide, assuming around 24 drops per ml. Note that the Taylor dropper bottles are around 26 drops/ml.

[Dietitian]

Currently my water arrives with about 3ppm FC and 2ppm combined chlorine, PH 9, and 600 ppm TDS. The water routinely falls out of spec as well. This summer the water contained unsafe ammonia levels for three months. We were notified this winter of the error.

Yikes! No wonder you taste the chlorine. Our water used to have < 1 ppm FC by the time it got to our house and now with monochloramine it's 1.2 ppm, but still hard to taste the chlorine or monochloramine itself. In our situation, the "bad" taste is mostly from other things in the water.

The combination of 3 ppm FC with 2 ppm CC is a bit of a concern. It would seem that the CC is persistent since if it started out as ammonia it should have been oxidized by the time it got to your house. So it may be some sort of organic that is slower to oxidize.

I don't know if hydrogen peroxide will be a strong enough reducing agent to dechlorinate the CC. It will certainly be able to remove the FC. You could certainly try it to see how it works by measuring the FC and CC after treatment. Add enough treating the CC as if it were FC in terms of calculating the amount of hydrogen peroxide needed. So to get rid of 5 ppm FC+CC in one gallon, it would take about one drop of 3% hydrogen peroxide, assuming around 20 drops per ml. Note that the Taylor dropper bottles are around 26 drops/ml.

According to this page, one drop of water is 0.025 ml, which would be 40 drops per ml. Does that seem correct? I assume that water drops change with the TDS and chemical levels, surfactants in the water, etc....

http://74.125.95.132/search?q=cache:VGRHmc...lient=firefox-a

[quantumchromodynamics]

Hydrogen peroxide can show up in a CC test.

[chem geek]

According to this page, one drop of water is 0.025 ml, which would be 40 drops per ml. Does that seem correct? I assume that water drops change with the TDS and chemical levels, surfactants in the water, etc....

http://74.125.95.132/search?q=cache:VGRHmc...lient=firefox-a

Those would be very small drops. I've corrected my post as it's actually 24 drops per milliliter for the Taylor bottles. As for what is standard, do a Google search for "drops per ml" and you'll find many sources, but it's most commonly 20 drops per ml.

Hydrogen peroxide can show up in a CC test.

That's too bad about hydrogen peroxide showing up as CC, though that makes sense since it will oxidize the potassium iodide that is added in the CC test and the resulting iodine reacts with the dye to show as CC. Oh well.