Experiment: PBW vs Oxyclean vs Homemade PBW

I've been wanting to test my various cleaning products for a while and finally did it last night. The tests I conducted, corresponding to the jars from right to left in the pics, are as follows:

Furthest right
6) Control - Tap Water
5) PBW in Tap Water
4) Homemade PBW - I used the recipe here [thread]467655[/thread]. It consists of 47% sun oxygen cleaner, 31% TSP/90 (sodium metasilicate), and 27% 7th Gen Dishwashing soap. Used RO water
3) Sun Oxygen Cleaner (walmart knock off of oxyclean versatile) in Tap Water
2) Homemade PBW in tap water
1) Homemade PBW in tap water, but this time I added 2% EDTA to try and help combat my hard water.
Furthest left

Here are the dirty mason jars I used. I tried to dirty them up all pretty evenly using some dme and hop gunk:




I added 1/2 tbsp of cleaner to each of the jars, which is roughly equivalent to 1 scoop of PBW per gallon. All water added was 170F

And they're off!

You can see oxyclean is foaming the most, and my homemade pbw is foaming a little.

And here they are after an hour sitting in my 145F oven to keep the temp up:


And here are the final results:



I thought I might be biased, so I had my roomate blindly inspect them and rate them by how dirty they were. He ranked them:
10 = very dirty 1= very clean
9 - Tap Water
6 or 7- Oxyclean
5 - Homemade PBW
4 - Homemade PBW + EDTA
2 - Real PBW
2 - Homemade PBW + RO Water
I completely agreed with his ranking

Conclusions:

Hard water sucks! Please note that when I say hard water, I mean my tap water is 700ppm TDS, so its pretty bad here in Los Angeles. Even my RO water ends up being about 40ppm TDS.

Using just water was pretty useless as expected.

Oxyclean seems to be kinda useless in hard water as well.

My Homemade PBW is a little better, and adding EDTA improved it slightly.

Real PBW kicks ass in hard water! However, if I use RO water, my much cheaper PBW substitute seems to work equally well.

So there you go, looks like for now I'll be mostly using my homemade PBW with hot RO water. Maybe if I add more EDTA I can use tap water.

I plan on doing this experiment again using all RO water and creating different homemade PBW mixes to find out what is the most effective and cheapest.

 

Excellent!

I missed it, what is "EDTA", please Sir?

 

ethylenediaminetetraacetic acid.

it's a chelating agent...it pulls hard water ions out

 

Specifically magnesium and calcium.

 

Is "tetra sodium EDTA" that same thing? Interested in augmenting a CIP system with this stuff. Can anyone help me with dosing suggestions..or is "2%" that the OP used a good rule of thumb.

 

It's a guess but that seems to be the non-ionized name

 

There are two types of EDTA, tetrasodium and disodium. If I remember correctly, generally disodium is used with acids and tetrasodium is used with bases, so I am using tetrasodium edta that I got off ebay. I also believe you need to use larger quantities of tetrasodium than disodium.

As for the 2%, thats just an estimate I made and not very scientific. Also, it clearly failed and wasn't enough in my test. I think you can calculate exactly how much edta will chelate how many hard water ions, so I plan on figuring that out and determining exactly the amount I would need for my specific water. In other words, for your purposes the amount of edta you will need is directly proportional to the quantity of calcium and magnesium in your water.

I need to do more research on this, I'm betting someone here knows more. I also have some citric acid I plan on messing with as an alternative chelator.

 

This is somewhat of a resurrection, but has anyone made progress on ideal EDTA concentrations?

 

resurrecting because you directed me here from the homemade pbw thread. This is well done.

Can you post a description of the process you used to gunk up the jars?

 

I wanted to add... I had some issue with residue. Added citric acid, which is cheap and accessible, and have no issue with residue or foaming now with my tap water.

 

Sure!

I took some dme and dissolved it in a little bit of water, then I added some used pellet hop gunk. This made a nice, thick, gross looking slurry. I put equal amounts of slurry in each mason jar, shook it up, and stuck it in the oven to bake it on. I'd shake it up periodically, and once the jars looked nice and disgusting I began the experiment.

 

Yeah I eventually tried that as well and adding citric acid definitely helped. The only problem was that my water is so hard that I needed to add a lot. This caused the pH to drop considerably, and seemed to negatively effect the cleaning power of the mixture. EDTA didn't drop the pH as much, but seemed to be less effective in similar quantities.

I do now add a half spoonful of citric acid to my dishwasher and my glasses come out sparkling crystal clear now =)

 

Bottom line PBW is really good stuff. If it cost a nickle for 10 pounds we would all be using it. And be very happy about it.

Personally, I have had bad experiences with Oxyclean. I do not bother with it. Even to the the point I will not consider the Oxyclean plus other stuff to make PBW substitute.

Saving a few bucks over the course of a year, is not worth the trouble. Then again I am a right tool for the job kind of guy. PBW has never let me down, so I pay a bit more and let it do it's thing.

 

you said you used hard water... i'm assuming you mean you don't have a water softener? ever try the experiment with soft water?

 

I wonder how regular oxyclean works with RO water. From my understanding the stuff added in PBW was to combat hard water but the cleaning agent's are similar to oxyclean.

As for myself, I have extremely hard water also, so I might need to stick to PBW instead of oxyclean (or try the experiment with RO water).

 

i have hard water myself but have a water softener and from what i've read soft water plays nicer with cleaning agents like oxyclean.... i'm going to be trying oxyclean (or knock off) with TSP90 and maybe seventh generation dishwashing detergent... from what i read it's pretty close to PBW ingredients.

 

I should redo this experiment with my extremely soft water to see how different the results are. I've been using Oxyclean and it seems to work really well for me. Our water comes from a shallow well and is basically last year's rain.

 

My understanding is seventh gen dish powder has the cheating agent in it that makes this work in hard water. But this experiment seems to indicate it doesn't work so well in hard water as standard pbw

 

I can chime in a little bit here: Using homemade PBW with my (hard) Toronto water, I rinse my bottles in water and then immerse for a while in starsan - seems to help somewhat with the residue.