We live in the country and use a septic tank. I don't use bleach because it kills the good bugs in the septic system.

But I was wondering:

Sodium Hypochlorite is NaOCl (sold commercially in water solution).

So, true or false?

It works by breaking down into oxygen, which is the bleaching agent, and sodium chloride, which is salt? (Free chlorine is also released into the air, you can smell it, so clearly the reaction isn't simply what i said. I googled sodium oxide and it says it reacts violently with water, so it would not persist. But what about other byproducts of the reactions?)

I could use it to bleach clothes, but not in a container that goes into the system, such as my washing machine.

Then I could let it stand out of doors overnight, to complete degassing.

Then the result would be salty water, which I can discard away from the well field with little ecological damage. (The amount is fairly small.)

Is this right?

Motto: A little knowledge is a dangerous thing.

Sodium Hypochlorite. Bleach Forms hypochlorous Acid H0Cl in solution.

The chlorine in the hypochlorite Ion is in the +1 oxidation state.
The bleaching action the chlorine is reduced to
-1 chloride state gaining 2 electrons in the process. (oxidizing other things that give up their electrons).

OCl- + 2H20 + 2e- ---> Cl- + 2(0H-)

You are correct that you'll end up with a high pH salty water. but it's the Chlorine that is doing the bleaching.

Some of the Bleachy smell is due to the reaction of the bleach with amines..
The familiar 'pool' smell is dichloramine
NHCl2. A fairly volitile material with limited solubility in water.

overnight will reduce the potency of the bleach but daylight will deplete it faster as the bleach is photo reactive (That's why they sell it in opaque bottles.

Wow, great answer, peeteo. So let's see if I've 'got' it:

If I let the used bleach water stand all day, it will give up more chlorine than if I let it stand overnight. (I guess a sniff will tell me if it is all right to spill out on waste ground after one day. If I can still smell bleach, I should let it de-gas longer.)

The other chemical byproducts of the breakdown of the used bleach are not terribly toxic to plants and animals and groundwater in limited quantities. (Might kill some bugs and worms I suppose but I'm not likely to use more than a gallon or so of solution (at the recommended concentration )at a time. I just bleach washcloths and towels, the people-kind and the dishes-kind. Occasionally some white cotton socks.)

If I don't hear back from you, I'll assume I'm safe to go.

Again, thanks.