Boron Additives

[MolaKule]

Quote:
potassium triborate - the most throughly covered boron additive. It may be enhanced by calcium carbonate?


I am not usre what you mean by CaC enhancement. The potassium triborate's additive package is mainly to enhance gear lube formulatons to increase load capacity and reduce tooth wear over pure S-P additive formulaions. It often includes a CaS or Ca Succinate additive for detergnecy-dispersancy and for rust protection. These additive packages also contains some additional anti-oxidants and metal inhibitors.


Quote:
Borated Sulphonates - huh? "Overbased"? Are these hydroxides?


For Grease formulations they could be.

Quote:
boric acid - mentioned as an Argonne Labs effort



Quote:
borate esters - sounds like a patent avoidance trick as esters then to be organic based


Not sure what you mean by "patent avoidance." The borate ester has been found to be synergistic with ZDDP and other AW and FM compounds, especially where AW additives like ZDDP are being reduced in engine oil formulations.

We need to keep in perspective that neither ZDDPs, molys, borates, antimonys, titaniums, tungstens, etc are the ultimate additives in and of themselves.

Much research has gone into the effects of using these additives in combination with various base oils and one must carefully formulate and test to determine the efficacy of these additives in combination.

I applaud your research and interest in the borates tbut there is much more to additive technology than just one element of the periodic table.

 

[DrScientist]

Originally Posted By: MolaKule

We need to keep in perspective that neither ZDDPs, molys, borates, antimonys, titaniums, tungstens, etc are the ultimate additives in and of themselves.

I applaud your research and interest in the borates tbut there is much more to additive technology than just one element of the periodic table.


How many useful additives are there in total? It seems like there are a heck of a lot. Are there any that should never be mixed?

 

[MolaKule]

Quote:
How many useful additives are there in total?


If you're talking about Over-the-Counter engine oil additives, none of which I am aware.

Slick marketing and wild claims may capture the imagination, but mostly capture your pocketebook.

What kind of perceived problem are you trying to fix?

For example, if you have a high mileage smoker and will be getting it rebuilt eventually, a thicker mineral oil would be better than using STP blue bottle or Motor Honey polymers.

If you do racing then use a racing oil, but the current list of name brand mineral/synthetic and boutique oils are sufficient for the daily driver applications WITHOUT any additives.

Now if you bought a used vehicle and suspect sludging or stuck rings, then you can take a chance with some of the OTC engine cleaners, or do frequenct oils changes with some of the latest oils.

 

[Mixologist]

MolaKule, what are your thoughts on using adding dry hBN in engine oil?

My take, at least as I understand it is that boric acid requires access to air/water + heat in order to become effective as a friction modifier/EP additive hence it would be better suited in non-engine oil duty. However, hBN as a dry additive seems to function the same as say potassium triborate and a borate ester compound or have I missed something?

 

[MolaKule]

Agreed, non-engine oil duty.

I would recommend against adding it to motor oil since, without testing, we not know how much to add nor the effect of the resulting chemistry.

 

[Mixologist]

Originally Posted By: MolaKule
Agreed, non-engine oil duty.

I would recommend against adding it to motor oil since, without testing, we not know how much to add nor the effect of the resulting chemistry.


MolaKule:

The reason I ask is because I've seen it (dry sub-mirco hBN) added to engine oils in the weight range and it seems to have positive results (previous job). However this was done as a treatment for the intensifier portion of a injector (oil pressure actuating the fuel injector) on industrial engines (Ship/gen-sets/etc..). hBN seems to be relatively chemically inert, i.e. polar but fairly nonreactive, instead relying on heat/pressure to bind to a substrate.

Do you see a scenario where this could be effective without skewing the base oil's DI-pack/Ph/etc..?

 

[dustyroads]

I love this paper molakule! I have read it a few times over the last year or so. I have to refresh and I understand it better each time.

I have been trying different HDEO's over the last year and the one with about 500 ppm of boron (in virgin form) makes my engine stunningly quieter. There are eight or nine (big) gears meshing in there and the cam is under a severe load in modern diesels.

Maybe it has nothing to do with the boron but it has me anxious to try chevron's delo esi 80w90 gear oil (with boron) in my (whining) differentials. It is approved for 500, 000 mile intervals despite being a mineral oil.

In my engine oil, the boron (in ppm) disappears at a steep rate (down to under 100 ppm after 25k miles). My question; does the type of boron in gear oil "stick around" so to speak? Or does the lack of internal combustion and not such intense heat allow it to maintain higher ppm?

BITOG member Yucca posted a voa of a chevron gear oil last year showing a little over 200 ppm (maybe 225 ?) Not sure if it's exactly the same oil I'm looking at, though.

Was hoping for a comment regarding the life of boron in engine oil vs gear oil if you have time. Sorry for the long winded question.

 

[dustyroads]

To simplify my previous post....if I do a VOA on gear oil that shows 225 ppm of boron, will it disappear at a rapid rate (like it does in my engine) and show very little boron in say...100k miles ?

If I use the mentioned product, I will probably do multiple UOA's to track how it's doing.

 

[MolaKule]

Please do get analysis.

You say it decreases, but where would the boron go?

My theory is the boron decreases one might see in analyses is due to testing variations and the masking of boron by increased acid levels in used lube.

 

[dustyroads]

The oil I'm so amazed by is good ol' Delo 400 LE. The voa I did about 18 months ago showed 497 ppm of boron. Other voa's I've seen have shown mid 400's to 600+ ppm.

UOA's of the same oil in diesel pickups seem to stay well into the 400's ppm of boron. In my truck (heavy duty use) I have 3 examples so far.

After 400 hrs = 248ppm

After 560 hrs = 120 ppm

After 679 hrs = 92 ppm

Those examples were what got me wondering where the boron goes. I wondered if it was a sacrificial additive that plated to the metal and no longer showed in analysis. That was my uneducated guess.

After looking at the pickup truck uoa's and how little the boron drops, I'm now guessing that the boron in gear oil will be maintained at near voa levels. I will be buying the delo esi gear lube and getting a voa later this year. My hope is that it will quiet down my whining differentials.

Your theory of the boron being masked by acids is way beyond my comprehension. Again, the sharp drop in boron in my truck's uoa's made me wonder what happens to it and would it do the same in gear lube. I should have thought about the other uoa's, too.

Thanks for the white paper. I am fascinated by boron even if I don't understand it on your level. I can't wait to see if it quiets my diffs!

After some sleep I may be able to ask something more. Thanks molakule!

 

[MolaKule]

An interesting test would be to track the TAN verses boron content at various mileages of the HDD oil.

Different types of boron compounds are used in gear oils verses PCMOs and HDDs.

For gear oils, the phosphorylated borates or potassium borates are used.

For PCMOs and HDDs, the esterified borates are used.

I do not have a definitive answer at this time but I am currently doing some further research on the topic of boron lubricants so if some kind of explanation comes fortth, I will update here.

 

[dustyroads]

Originally Posted By: MolaKule
An interesting test would be to track the TAN verses boron content at various mileages of the HDD oil.


That is my plan for both the HDEO and the gear lube. With the engine oil there are idle hours included with operation so I was thinking I would do 100 hour samples. That would get me four, five or possibly six uoa's in an oci (after a fresh voa of course). I'll have to get my "ducks in a row" for that.

The gear oil would start with a voa and maybe 50k to 100k mile samples to watch the boron and acid. Probably starting in the last quarter of this year.

Chevron mentions the inorganic borate in their gear oil info sheet multiple times, implying the boron makes it superior. Since it is approved for 500k mile intervals, the boron must "stick around".

 

[BLKGTTDI]

On this white paper about boron if I read correctly it implies it doesn't require heat to bond with metal?

However this implies that boron DOES require heat?

http://www.machinerylubrication.com/Read/1406/extreme-pressure-additives

"There are two main types of EP additives, those that are temperature-dependent, and those that are not. The most common temperature-dependent types include boron, chlorine, phosphorus and sulfur. They are activated by reacting with the metal surface when the temperatures are elevated due to the extreme pressure. The chemical reaction between the additive and metal surface is driven by the heat produced from friction."

I'm a little confused any help is appreciated.

 

[MolaKule]

It also says,

Quote:
There are two main types of EP additives, those that are temperature-dependent, and those that are not. The most common temperature-dependent types include boron, chlorine, phosphorus and sulfur.


I don't know when this was written but chlorinated additives are no longer used in gear lubes.

Most gear lubes contain primary and secondary EP additives. The primary EP additive has been a sulfur-phosphorous chemistry for the high temperature EP regime. Later formulations are going with a multi-functional phosphorus ester. The lower temperature secondary additive is usually a tri-sodium or tri-potassium borate ester.

Quote:
The nontemperature-dependent, overbased sulfonate, operates by a different mechanism. It contains a colloidal carbonate salt dispersed within the sulfonate. During the interaction with iron, the colloidal carbonate forms a film that can act as a barrier between metal surfaces, much like the temperature-dependent; however, it does not need the elevated temperatures to start the reaction.


Sounds very similar to a tri-sodium or tri-potassium borate ester.

The tri-sodium or tri-potassium borate ester is a colloidal mixture of tri-sodium or tri-potassium borates suspended in an ester.

Again, I don't know where this guy is coming from but I doubt he is a formulator. Colloidal carbonate salts dispersed within sulfonates are usually used in greases with other compounds.

You might also check out:

Gear and Lube Tribology I

Gear and Lube Tribology II

 

[BLKGTTDI]

Originally Posted By: MolaKule
It also says,

Quote:
There are two main types of EP additives, those that are temperature-dependent, and those that are not. The most common temperature-dependent types include boron, chlorine, phosphorus and sulfur.


I don't know when this was written but chlorinated additives are no longer used in gear lubes.

Most gear lubes contain primary and secondary EP additives. The primary EP additive has been a sulfur-phosphorous chemistry for the high temperature EP regime. Later formulations are going with a multi-functional phosphorus ester. The lower temperature secondary additive is usually a tri-sodium or tri-potassium borate ester.

Quote:
The nontemperature-dependent, overbased sulfonate, operates by a different mechanism. It contains a colloidal carbonate salt dispersed within the sulfonate. During the interaction with iron, the colloidal carbonate forms a film that can act as a barrier between metal surfaces, much like the temperature-dependent; however, it does not need the elevated temperatures to start the reaction.


Sounds very similar to a tri-sodium or tri-potassium borate ester.

The tri-sodium or tri-potassium borate ester is a colloidal mixture of tri-sodium or tri-potassium borates suspended in an ester.

Again, I don't know where this guy is coming from but I doubt he is a formulator. Colloidal carbonate salts dispersed within sulfonates are usually used in greases with other compounds.

You might also check out:

Gear and Lube Tribology I

Gear and Lube Tribology II


Thank you for the links I will have a read!

 

[AITG]

I'm reviving this thread from anchient history to ask a practical question: I am a constant UOA user over the last 25 years so my vehicles have factory fill to end of life histories. As I review the UOA data the boron content drops over time as Kule noted. My question is how low can the content drop and still be serviceable? I do have VOA data on the oil I'm using so I know where I started.

 

[MolaKule]

Boron can be incorporated with a number of chemical agents as a Multi-Functional additive within an ester but is mostly a low temperature Anti-Wear component.

Is this an HDD application or a passenger vehicle or light truck engine oil.

We have found there may be two reasons Boron levels appear to show reduction, but this reduction seems rare.

1. Boron can be encapsulated in soot particles and may not flash-off properly to be shown in Fourier IR traces,
2. the Boron ester component is of such a low viscosity it may evaporate a bit sooner than other additive components.

But don't take these statements as gospel since research is still ongoing.

I know of no rule (comparable to TAN/TBN levels) in which there is a condemnation level based on Boron ppm levels alone.

 

[whizbyu]

OK so what is the TAKE HOME message here?