Citric vs. Oxalic

[the_GUNN_man]

I was just wondering which people prefer and why. Is one better then the other? I think that citric is supposed to be safer then oxalic. I know people use oxalic on concrete, does citric work like oxalic on concrete? Also was curious about the citric/oxalic acid mixed? I know some people sell a mixed version of that. Any comments about the premixed stuff?

 

[oneness]

I just did a fence this weekend, approx. 800' long. I used a percarbonate cleaner mix, which worked well. However, the brightener mix I used didn't seem to do anything at all. I used a 70/30 mix, by weight, of oxalic and citric acids, 2 1/2 lbs for a 5 gallon bucket. Applied it with an x-jet and.......nothing! Went back the next day and....nothing! I only applied this to a portion of the fence, and could see absolutely no difference in the treated and untreated areas. Is there a flaw in my mixing proportions, the amount per 5 gallons of water, or is it possible the wood was just as bright as it was going to get? It was a 5 year old fence, not sure the wood type but definitely not PT. It WAS awfully bright when I was done. Any suggestions?

Thanks!

 

[Aplus]

My guess is your percarb mix brightened the wood as much as it was going to get. In your case, the ratio of oxalic/citric blend sounds right, but likely would have only neutralized, rather than brightened.

 

[oneness]

That's kind of what I figured. Thanks for the confirmation!

 

[rvagnoni]

Mike,

I believe your mixing ratio was fine but the fact that you applied the brightener with your xjet most likely diluted the mixture.

 

[Mike Hughes]

I agree with Rick.........the xjet dilluted it too much. We apply brightner with a shurflo or a pump up sprayer.

 

[oneness]

So if I were to apply it with the X-jet, I could just mix it at a little over twice as strong, since the X-jet draws around 2.4:1 on my machine...??? Tried that today, actually, and I noticed a slight difference in the wood after applying, but nothing like I noticed on my own deck when I brightened it. It is made from Cypress, and was never treated. I'm assuming wood type would make a difference also? The deck I did today was entirely PT pine. Cleaned up nicely, but definitely had room to brighten. Am I safe in the assumption that some woods just brighten more than others?

 

[the_GUNN_man]

Gee thanks everyone for answering my question.

 

[Mike Hughes]

I dont think you could mix it "twice as strong". Some chemicals you can only mix to a certain strenght, but I'm not sure.

 

[oneness]

Well, it all dissolved into the water, so I'm assuming it was twice as strong.

 

[ron]

i am not being argumentive but what mike ment was like if you add bleach to bleach both 6%sh
you dont get 12% sh.
there are other chems that are the same way.
Some that you try, will just be wasteing your chem.

 

[Mark]

I know from past experience with caustic cleaners, that after a certain percentage you can not hold anymore caustic in that solution as it will begin to crystallize.

 

[oneness]

ron:

I agree with what you're saying, but it isn't really the same thing. If I add 1 gallon of 6% bleach to another gallon of 6% bleach, all I'm doing in increasing volume at the same rate as I'm increasing concentration. However, if I had powdered chlorine and it took 1lb added to 1 gallon of water to make 1 gallon of 6% chlorine solution, then if I added 2lbs to 1 gallon I should get 1 gallon of 12% chlorine solution. That is only if, as Mark points out, I don't reach the point where no more powder will dissolve in the water.

Since all the powder did dissolve in the water, when I applied it with an x-jet at a 2:1 ratio, I should have had the same concentration on the deck as if I had mixed it half as strong and applied with a pump up sprayer.

While I'm sure there is a point at which the solution is as strong as it can be, I don't think I reached it since all the powdered acid dissolved in the water.

 

[HeavyChevy]

Hey Steve.....Did you EVER get an answer to your original question, which was the WHOLE topic of this particular thread???

"I was just wondering which people prefer and why. Is one better then the other? I know people use oxalic on concrete, does citric work like oxalic on concrete? Also was curious about the citric/oxalic acid mixed? I know some people sell a mixed version of that. Any comments about the premixed stuff?"

Let me know, because I was wanting/needing the same answer.

 

[the_GUNN_man]

Yeah I know the subject got side tracked. I never really did get an answer. I went ahead and got the oxalic acid and I will do some testing on that soon. On my own stuff of course. I never experiment with a customers property. I know some who do that. Scary stuff.