[pcm81]

If I understand correctly, sodium hydroxide or some other base is the main ingredient in many degreasers. My question is: what is the benefit of using a commercial strength degreaser vs just sodium hydroxide solution? I think many de-greasers are less hazardous, so you can handle them safer... But having said that, I have all of the proper safety gear for running hot caustic blackening bath (5lb of NaOH + 2lb of NaNO3 per gallon of water running at 290 degrees F), so is there any advantage for me to bother with commercial level degreasers or will i get the same or better result from a straight up low concentration NaOH bath?

[pcm81]

If I understand correctly, sodium hydroxide or some other base is the main ingredient in many degreasers. My question is: what is the benefit of using a commercial strength degreaser vs just sodium hydroxide solution? I think many de-greasers are less hazardous, so you can handle them safer... But having said that, I have all of the proper safety gear for running hot caustic blackening bath (5lb of NaOH + 2lb of NaNO3 per gallon of water running at 290 degrees F), so is there any advantage for me to bother with commercial level degreasers or will i get the same or better result from a straight up low concentration NaOH bath?

The "SuperClean" degrease that i have is pH=12. According to my calculations i would have to use 0.5 grams of NaOH per litre of water to get pH close to 12 (give or take 0.5 of pH based on temperature). Am I missing something or are the commercial degreasers just a rip-off and i can just use NaOH instead?

[billnotgatez]

@pcm81
Did you look at the Material Safety Data Sheet (MSDS)
for the product
Is "SuperClean" the only product you are interested in

[pcm81]

@pcm81
Did you look at the Material Safety Data Sheet (MSDS)
for the product
Is "SuperClean" the only product you are interested in

I am interested in the chemistry driving these products.
In many cases the MSDS will omit some ingredients as a "trade secret".

Specifically for super clean the MSDS states:  https://www.superclean.com/wp-content/uploads/2016/10/2016-SuperClean-Degreaser-SDS-v2.0.pdf
Sodium Metasilicate    <5
Sodium hydroxide       <5
Surfactant, blend        1-10

The units are Concentration wt/wt

I measured the pH of this degreaser (since i have a gallon of it) to be 12.01.

It seems to me, these types of products, similarly to drug industry, are many brand names that use slightly different formulations to differentiate themselves from each other; but they all are basically the same active ingredient.

My research so far revealed that Sodium Metasilicate is basically a coagulant/deflocculant agent, but if that is all that it is, them sodium phosphate or other phosphates should work as well or may be even better.  Based on my recent reading it seems that industry is moving away from phosphates and so silicates are now used. While that change makes sense on industrial scale to reduce phosphates leaching into ground water, for home use, would a sodium phosphate + sodium hydroxide be a better / cheaper / more effective degreaser than commercial solution at $25 per gallon?

I am basically trying to understand the chemistry and list of ingredients for de-greasers.

From what i gathered so far, an effective detergent should have 3 main components, a wetting agent, active ingredient and an emulsifier.
For metal oxides the active ingredient is some kind of acid. For grease and oil it is some kind of base.For example phosphoric acid and sodium hydroxide.
What would be other chemicals to fill the roles of wetting agent and an emulsifier for metallic (metal oxides) and organic (grease) dirt?
What other "dirt" types did i leave out?

Am I correct to say that a degreaser will chemically react with oil/grease to change it into a water soluble form, while something like alcohol will simply dissolve oil/greases while leaving their molecular structure intact? Hence when alcohol dissolves the grease and evaporates, the leftovers is grease again?

I know i am asking allot of questions that seem to be "all over the place"; but really i am just trying to get the "complete" big picture with "necessary properties" as well as list of common substances that can be used as components of cleaners. I am actually interested in chemistry behind the process of surface cleaning.

[billnotgatez]

From your original question I thought you wanted to know
could you use just Sodium hydroxide rather than a comercial degreaser.
It appears that the degreaser has other compounds in it that aid in cleaning.
I am assuming that they played with various combinations of compounds until they got something better than any one single compound.
Note the term

Surfactant, blend

(seems proprietary to me)
Hence the trade secret.
I suppose you can make your own combination of compounds that are better than the name brand.

[pcm81]

From your original question I thought you wanted to know
could you use just Sodium hydroxide rather than a comercial degreaser.
It appears that the degreaser has other compounds in it that aid in cleaning.
I am assuming that they played with various combinations of compounds until they got something better than any one single compound.
Note the term

Surfactant, blend

(seems proprietary to me)
Hence the trade secret.
I suppose you can make your own combination of compounds that are better than the name brand.

I guess i was looking for an answer in a form of:
Active ingredient in all degreasers is X, Y or Z
For a throwaway bath any strong base in a dilute solution of X moles yielding pH Y will work
Industrial baths also have bath stabilizers and cleaners (precipitators) to keep bath working longer consisting of chemicals XYZ. Irrelevant for a garage based throw away bath.
To aid cleaning, a wetting agent should be used. Common chemicals for alkali solutions are A, B C.

I am an engineer in real life. I like efficiency. And having a 1-car garage, storage efficiency is a plus. I'd much rather store couple pounds of sodium hydroxide and couple litres of phosphoric acid. plus couple pounds of other relevant chemicals, which would let me mix up 100 gallons of cleaning solution, as needed, than to store 100 gallons of cleaning solution.

[Borek]

My bet is that it is the surfactant that makes the difference. High pH will be etching many surfaces, adding a strong surfactant means you can remove the grease in a less corrosive conditions.

[Arkcon]

Its good that you had the MSDS, I was suspecting the best degreasers didn't have NaOH at all, but instead organic bases, likely mixed with surfactants that can survive pH.  Sodium metasilicate is commonly added to meat cleansers of all kinds to "protect" the metal, by some mechanism that I don't know.

If high pH is prone to etching steel surfaces, then, you may be able to reproduce the effect with and without sodium metasilicate and detergents.  Of course, there are many grades of steel, and you'll have to consider confined areas where cleansing agents can accumulate, and also possible welded/blazed joints, and their method, quality of joint, and if the joint is electropolished or otherwise cleaned up.

You have lots of work to do to advance your knowledge of your application, but it may not even translate to other situations.

[pcm81]

I did some math based on some assumptions and i am getting rater interesting results. Can you guys tell me if this makes sense or if i am off somewhere.

The MSDS for SuperClean is shown above. If i were to assume that they use Sodium Stearate as the surfacant i get a ph = 12 with the following concentrations per liter:
NaOH - 0.5g/L gives pH=12.096 (calculated assuming 100% dissolution)
Na2SiO3 - 1.25g/L gives pH=12.01 (calculated assuming 100% dissolution)
C18H35O2Na - 3g/L gives pH=11.991 (calculated assuming 100% dissolution)

So we have:
NaOH - 0.017% concentration
Na2SiO3 - 0.041% concentration
C18H35O2Na - 0.1% concentration.

I divided the g/L from above by 3 and converted to %.

Of course the exact ratios are a trade secret and i am assuming that surfactant is sodium stearate.. I am just curious if my calculations seem correct to you?