Neutralizing muriatic acid

[jmsrbrt]

I've got a tub of muriatic acid and water, 4 gallons, 50/50 ratio (two gallons acid, two gallons water) and have poured eight (8) pounds of baking soda in it, to neutralize the acid, It won't stop fizzing, which is an indication of it being safe to pour down the drain or on the grass (I've checked with the local boys, so don't say it can't be done). My question is...HOW much baking soda is it going to tak to make it safe to discard? Any chemists out here???

[ronsii]

Is this the muriatic acid that you get from hardware stores like home depot, lowes that is now 15% strength ??? or is this the regular 30 percent hydrochloric like from masonry supply houses? It will also depend on how much you have used/depleted the acid with what is being cleaned in it ie...rust covered parts or just slag.

As long as it is fizzing when soda is added it is still acidic

[jmsrbrt]

Got the Ph down to where it was neutral and all is well, however, before I mix up a new batch, I plan on doing an experiment with a small quantity and see how much water and baking soda it takes to get to the neutral Ph level...for future reference.

Btw, the acid is 35.45% by the label.

[aicomp]

Hi,
I'm juust curious as to what the muriatic acid is used ffor. Does it clean the rust and slag off of cut parts?
Thanks,
Mike

[BrianMick]

Hi,
I'm juust curious as to what the muriatic acid is used ffor. Does it clean the rust and slag off of cut parts?
Thanks,
Mike

Mike here is a link pertaining to this subject
Brian
http://www.plasmaspider.com/viewtopic.p ... cid#p15395

[aicomp]

Thank You Very Much.
Mike

[jmsrbrt]

Hi,
I'm juust curious as to what the muriatic acid is used ffor. Does it clean the rust and slag off of cut parts?
Thanks,
Mike

Mill scale removal mostly, but does a fine job on removing the dross from thinner metals. And once you clean it off, it is almost as shiny as polished metal.

[aicomp]

I'm going to pick some up today.
Thank You all for the replies.
Mike

[jmsrbrt]

Just an update, but it seems to me, from experimenting, that a solution of 1:8 (muriatic acid:water) is enough to get the Ph level down to around 7, i.e., neutral. No baking soda required. And my muriatic acid was the 34% kind...full strength I believe.