Removing zinc from my toxic rocket stove

I built a rocket stove from galvanised gas vent pipes.



I didn’t know that this could lead to the release of toxic gases. I then had the idea to remove the zinc with a bit of chemistry. Yesterday I cut two samples and put one in vinegar and the other in a solution made from water and citric acid crytals.



Here are the results:



Both look good.

On closer inspection the vinegar hasn’t worked as well as the citric acid solution.

Here’s the back of the one soaking in vinegar:



Here’s the back of the one soaking in citric acid:



Can anyone think of a reason why I can’t go ahead and soak the whole stove in a citric acid bath and turn it into a non toxic burner? It only needs to get me through the Food Prep Badge Bits - I’m going to build a proper stove next year.

Hi Ed;
Cool science project!
I guessed the citric acid might do a better job.

Here's the thing about galvi off gassing.
It a one time thing.
Let it rocket and puff your issues are gone.

However if your concern is the release of the gasses themselves.  
Since you already have galvi  try your citric bath it sure can't hurt.
Or.... use black pipe instead.

1. Have you actually read the label on each piece of pipe? I know that the piece supporting the wood is galvanized, but have you checked the labels on the other pieces?

2. A big danger from "galvanizing" is that when zinc is mined, lead comes along for the ride. The lead actually makes the galvanizing work better, but from reading Hubby and I have done, it can be difficult to determine as a typical homeowner, what the lead content is. When it's just sitting as a vent moving air around a house, the galvanizing should be pretty stable and not much of a threat. Outside exposed to acid rain, you can get what your experiment shows! So when they say that "burning releases toxic gasses", the fluid you're using to remove the galvanizing is doing that absorbing, so I'd be equally cautious with it! I'd have a disposal plan before getting started!

Good luck!