Something I was curious about since learning of the groups here on BOG, how is a group III different than say PYB at low temperature flow? Both made from Parrafin wax, right? Shouldn't they become a solid at relatively the same temp being as such? I understand that group III has more uniform molecules etc, but does that change the temp at which it would become a solid again?
Group III and low temperature flow
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Did you mean low temp viscosity of group 3 vs group 2?
Since the VI of group 3 is better than group 2, it's going to be lower, for the same 100C viscosity. Not by a huge margin though.
Since the VI of group 3 is better than group 2, it's going to be lower, for the same 100C viscosity. Not by a huge margin though.
Originally Posted By: friendly_jacek
Did you mean low temp viscosity of group 3 vs group 2?
Since the VI of group 3 is better than group 2, it's going to be lower, for the same 100C viscosity. Not by a huge margin though.
I guess my question is since they are both paraffin wax based etc., would they both become thicker and more of a solid at the same temperature and if that is not the case, what would make the group III different, especially being made from the same stuff basically? I get that the molecules are more uniform with group III due to more steps in refining etc, but how would that change it from becoming a solid at a different temperature than a group II or group II+.
Did you mean low temp viscosity of group 3 vs group 2?
Since the VI of group 3 is better than group 2, it's going to be lower, for the same 100C viscosity. Not by a huge margin though.
I guess my question is since they are both paraffin wax based etc., would they both become thicker and more of a solid at the same temperature and if that is not the case, what would make the group III different, especially being made from the same stuff basically? I get that the molecules are more uniform with group III due to more steps in refining etc, but how would that change it from becoming a solid at a different temperature than a group II or group II+.
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Wax is typically removed from lubricating oils due to precipitation as temperature decreases.
It doesn't have to turn solid for wax crystals to start to precipitate. They can precipitate and be held in suspension by the non-wax molecules. A test called Cloud Point is used for this, the temperature at which the oil will be almost solid is the Pour Point.
There are older technologies that chill the oil and use a rotary vacuum filter to remove the wax as a separate material.
There are newer technologies that use high temperature chemical reaction to rearrange the molecular structure of the wax changing it to lubricating oil - typically employing a catalyst (catalytic dewaxing, hydroisomerization).
It doesn't have to turn solid for wax crystals to start to precipitate. They can precipitate and be held in suspension by the non-wax molecules. A test called Cloud Point is used for this, the temperature at which the oil will be almost solid is the Pour Point.
There are older technologies that chill the oil and use a rotary vacuum filter to remove the wax as a separate material.
There are newer technologies that use high temperature chemical reaction to rearrange the molecular structure of the wax changing it to lubricating oil - typically employing a catalyst (catalytic dewaxing, hydroisomerization).
so would a group III become a solid at any temperature point? Or did the extra process(s) it goes through vs. a group II prevent that from being part of the equation? What I am getting from your explanation (which is quite good, thank you) is that since the group II do doesn't go through the chemical separation or less of the procedure anyways, that the group II still has ability to become a solid at low temperatures and the group III would not because the wax has been eliminated through hydro. Is that the jist of it?
To the OP: I think you are confused about what is made from paraffin wax. Group 4 can be made from paraffin wax, but group 4 is technically synthetic and therefore is chemically built from the base material being used. Group 3 is dewaxed (hydroisomerization for example), then severly hydrocracked to give it properties similar to group 4 oils.
The synthetic variant is more refined thus it's more pure and those waxes and impurities aren't there,thus their extended drain ability.
If you start off with a cleaner basestock it can last longer in service.
Or something like that......
If you start off with a cleaner basestock it can last longer in service.
Or something like that......
Yes, I was under the assumption the Group IV was not made from petroleum products such as Paraffin. Interesting. To me that would make me not want to pay extra$$ for a group IV over a much lower priced group III.
JHZR2
Staff member
Guess what, group IV and V also come from cat cracker offgas that is derived from waxy crudes. It's just reacted somewhat differently to produce and to process into a viable lubricant.
The whole group III comes from wax/crude gets old. There is no real value proposition in a finished product based upon the former characteristic of a feed product.
Some plots can be seen here:
http://www.machinerylubrication.com/Read/533/base-oil-trends
The whole group III comes from wax/crude gets old. There is no real value proposition in a finished product based upon the former characteristic of a feed product.
Some plots can be seen here:
http://www.machinerylubrication.com/Read/533/base-oil-trends
I didn't mean it as a bad or argumentative thing, just satisfying my knowledge and curiosity from knowledgeable fellow members here. I know when looking at msds sheets and a lot or all of group III sheets state the main component being highly refined mineral oil and some just stating paraffin, this is where my confusion came into play and left me wondering what made the III different than II when it comes to very low temperatures and the ability of paraffin to become solid in form since both are essentially refined crude oil or so I thought. Its all about knowledge and information man, I will only believe I have enough knowledge when I am dead
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The technical data sheets tell the story. Using Quaker State Advanced Durability (largely Group II) and Quaker State Ultimate Durability (largely Group III) 5w/20s as examples:
QSAD:
cST @ 100C: 8.2
CCS @ -30C: 4,790
MRV @ -35C: 12,100
QSUD:
cST @ 100C: 8.68
CCS @ -30C: 3,480
MRV @ -35C: 9,600
So, despite being slightly thicker at operating temperature, the Group III QSUD is quite a bit "thinner" at very cold temperatures. So even though both start with crude oil, the additional processing and resulting more uniform molecule size in a Group III oil do make a difference. Plus, it's likely Group II oils need more pour-point depressants than Group III to achieve a lesser result.
QSAD:
cST @ 100C: 8.2
CCS @ -30C: 4,790
MRV @ -35C: 12,100
QSUD:
cST @ 100C: 8.68
CCS @ -30C: 3,480
MRV @ -35C: 9,600
So, despite being slightly thicker at operating temperature, the Group III QSUD is quite a bit "thinner" at very cold temperatures. So even though both start with crude oil, the additional processing and resulting more uniform molecule size in a Group III oil do make a difference. Plus, it's likely Group II oils need more pour-point depressants than Group III to achieve a lesser result.
The ethylene used to manufacture polyalphaolefin (PAO) for Group IV is most definitely derived from petroleum via catalytic cracking and / or steam cracking and / or dehydrogenation of ethane.
The definition of the pour point test is listed here in this link.
http://en.wikipedia.org/wiki/Pour_point
Note that it's the temperature at which the material does not flow when the container is held horizontally for 5 seconds (via the 'old school' method I grew up with). It doesn't mean it won't flow when turned upside-down for 5 seconds for example, or held horizontally for more than 5 seconds as another example. Now whiz-bang advanced apparatus is typically used for pour point measurement.
So is a specimen's pour point temperature the temperature when it's a solid? Not really, but it can be used as a convenient repeatable test for when it's pretty close to solid.
The much greater population density of highly branched paraffinic molecules in Group III oils typically yield a lower pour point temperature than typical Group II oils. As mentioned there are also pour point depressant additives used in some lubricating stocks as well as many diesel fuels to lower the pour point test result. The effectiveness of such additives is highly dependent on the molecular structure of the base oil those are added to.
The definition of the pour point test is listed here in this link.
http://en.wikipedia.org/wiki/Pour_point
Note that it's the temperature at which the material does not flow when the container is held horizontally for 5 seconds (via the 'old school' method I grew up with). It doesn't mean it won't flow when turned upside-down for 5 seconds for example, or held horizontally for more than 5 seconds as another example. Now whiz-bang advanced apparatus is typically used for pour point measurement.
So is a specimen's pour point temperature the temperature when it's a solid? Not really, but it can be used as a convenient repeatable test for when it's pretty close to solid.
The much greater population density of highly branched paraffinic molecules in Group III oils typically yield a lower pour point temperature than typical Group II oils. As mentioned there are also pour point depressant additives used in some lubricating stocks as well as many diesel fuels to lower the pour point test result. The effectiveness of such additives is highly dependent on the molecular structure of the base oil those are added to.
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The Group V pale oils produced at the first facility I worked at after finishing college had nothing to do with steam cracking or any type of catalytic cracking. These were produced from a special grade of crude oil to produce 'blue lubes' and the various fractions were hydrotreated in block operation to produce pale oils.
Be careful the way you think about "made from". Smoke can be made from wood. Barns can be made from wood. Smoke is not similar to barns. There is a lot of chemistry that goes into hydrocracking. You end-up with chemicals that are different from the starting material. It is not a purification. Group III is NOT purified Group II. It is chemically modified Group II.
Hydrotreating is not hydrocracking - be careful you don't get too mixed up in the different technologies and severties of applications involving hydrogen.
Hydrocracking does not result in olefins - there is a very high hydrogen partial pressure so bonds are very rapidly saturated, making hydrocracking an exothermic process. It is not used to produce olefins.
Fluid catalytic cracking is endothermic and produces (some) olefins.
Steam cracking is endothermic and produces (some) olefins.
Dehydrogenation of ethane to produce ethylene produces olefins.
How many years experience do you have in petroleum & petrochemical production?
I started working with catalytic reforming and hydrotreating in 1990.
I started working with fluid catalytic cracking in 1991 and hydrocracking in 1993.
I worked around steam crackers from 1988 to 1990.
Hydrocracking does not result in olefins - there is a very high hydrogen partial pressure so bonds are very rapidly saturated, making hydrocracking an exothermic process. It is not used to produce olefins.
Fluid catalytic cracking is endothermic and produces (some) olefins.
Steam cracking is endothermic and produces (some) olefins.
Dehydrogenation of ethane to produce ethylene produces olefins.
How many years experience do you have in petroleum & petrochemical production?
I started working with catalytic reforming and hydrotreating in 1990.
I started working with fluid catalytic cracking in 1991 and hydrocracking in 1993.
I worked around steam crackers from 1988 to 1990.
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JHZR2
Staff member
Originally Posted By: Nyogtha
The Group V pale oils produced at the first facility I worked at after finishing college had nothing to do with steam cracking or any type of catalytic cracking. These were produced from a special grade of crude oil to produce 'blue lubes' and the various fractions were hydrotreated in block operation to produce pale oils.
So you think.
Many things come from light fractions of gas and gaslike products coming out of cat crackers. Some of it is steam reformed to carbon monoxide and hydrogen, some is made into other stuff. The chemists are good at finding pathways from this to that, and the engineers are good at splitting that from the other things, since NO reaction is anywhere near 100%.
And a lovely other point - even pure synthesis reactions produce a LOT of waxes and other nasty byproducts... So a PAO product stream can have heavy waxes in it, ditto for FT alkanes and saturated isomers and other processes. Are those waxes OK while skack wax from a hydrotreater is bad? LOL.
The Group V pale oils produced at the first facility I worked at after finishing college had nothing to do with steam cracking or any type of catalytic cracking. These were produced from a special grade of crude oil to produce 'blue lubes' and the various fractions were hydrotreated in block operation to produce pale oils.
So you think.
Many things come from light fractions of gas and gaslike products coming out of cat crackers. Some of it is steam reformed to carbon monoxide and hydrogen, some is made into other stuff. The chemists are good at finding pathways from this to that, and the engineers are good at splitting that from the other things, since NO reaction is anywhere near 100%.
And a lovely other point - even pure synthesis reactions produce a LOT of waxes and other nasty byproducts... So a PAO product stream can have heavy waxes in it, ditto for FT alkanes and saturated isomers and other processes. Are those waxes OK while skack wax from a hydrotreater is bad? LOL.
Originally Posted By: JHZR2
Guess what, group IV and V also come from cat cracker offgas that is derived from waxy crudes. It's just reacted somewhat differently to produce and to process into a viable lubricant.
The whole group III comes from wax/crude gets old. There is no real value proposition in a finished product based upon the former characteristic of a feed product.
Some plots can be seen here:
http://www.machinerylubrication.com/Read/533/base-oil-trends
I couldn't quickly determine the date of that Machinery Lubrication article (I'm guessing about 10 years old) but it's amazing how much PCMOs have changed. It predicted "0W-20 and 0W-30 oils will be PAO based at least for the next 5 years". Of course that was before the Japanese OEMs developed GP III 0W-20s. Now with one or two exceptions all OEM and API 0W-20s are GP III
plus a few 0W-20 syn blends.
Guess what, group IV and V also come from cat cracker offgas that is derived from waxy crudes. It's just reacted somewhat differently to produce and to process into a viable lubricant.
The whole group III comes from wax/crude gets old. There is no real value proposition in a finished product based upon the former characteristic of a feed product.
Some plots can be seen here:
http://www.machinerylubrication.com/Read/533/base-oil-trends
I couldn't quickly determine the date of that Machinery Lubrication article (I'm guessing about 10 years old) but it's amazing how much PCMOs have changed. It predicted "0W-20 and 0W-30 oils will be PAO based at least for the next 5 years". Of course that was before the Japanese OEMs developed GP III 0W-20s. Now with one or two exceptions all OEM and API 0W-20s are GP III
plus a few 0W-20 syn blends.
Here's a good succinct overview of hydroprocessing technologies employed with the manufacture of lubricating oils.
http://www.machinerylubrication.com/Read/493/base-oil-technology
Here's a good article on hydroisomerization. Note this is not hydrocracking, and appears to be a part of a college chemical engineering course.
http://www.chbe.northwestern.edu/docs/Hydroisomerization-Class-Presentation_v2.pdf
Note this is also not some sort of a purification step.
Here's a technology blurb from ExxonMobil (EMR&E) regarding their hydrocracking process for producing lubricating oils - and notice this is followed by catalytic dewaxing and hydrotreating.
http://www.exxonmobil.com/Apps/RefiningTechnologies/files/sellsheet_lhdc.pdf
Other technology companies of course have their own proprietary designs to accomplish the same goal.
Here's a Wikipedia article on fluid catalytic cracking, since it's more generic you can see some of the differences different technology vendors employ. You can also see how different the chemistry is than a hydrocracker, although both processes use similar (in some cases the same) feedstocks.
http://en.wikipedia.org/wiki/Fluid_catalytic_cracking
http://www.machinerylubrication.com/Read/493/base-oil-technology
Here's a good article on hydroisomerization. Note this is not hydrocracking, and appears to be a part of a college chemical engineering course.
http://www.chbe.northwestern.edu/docs/Hydroisomerization-Class-Presentation_v2.pdf
Note this is also not some sort of a purification step.
Here's a technology blurb from ExxonMobil (EMR&E) regarding their hydrocracking process for producing lubricating oils - and notice this is followed by catalytic dewaxing and hydrotreating.
http://www.exxonmobil.com/Apps/RefiningTechnologies/files/sellsheet_lhdc.pdf
Other technology companies of course have their own proprietary designs to accomplish the same goal.
Here's a Wikipedia article on fluid catalytic cracking, since it's more generic you can see some of the differences different technology vendors employ. You can also see how different the chemistry is than a hydrocracker, although both processes use similar (in some cases the same) feedstocks.
http://en.wikipedia.org/wiki/Fluid_catalytic_cracking
CATERHAMI couldn't quickly determine the date of that Machinery Lubrication article (I'm guessing about 10 years old) [/quote said:
Originally Posted By: JHZR2
Originally Posted By: Nyogtha
The Group V pale oils produced at the first facility I worked at after finishing college had nothing to do with steam cracking or any type of catalytic cracking. These were produced from a special grade of crude oil to produce 'blue lubes' and the various fractions were hydrotreated in block operation to produce pale oils.
So you think.
No - so I know.
I pasted in a number of educational articles for you, including the chemistries involved. This know-how is in the public domain, you just need to understand what you're reading.
Here's a link regarding the production of pale oils I mentioned just for you.
http://www.valero.com/products/pages/baseandprocessoils.aspx
Originally Posted By: Nyogtha
The Group V pale oils produced at the first facility I worked at after finishing college had nothing to do with steam cracking or any type of catalytic cracking. These were produced from a special grade of crude oil to produce 'blue lubes' and the various fractions were hydrotreated in block operation to produce pale oils.
So you think.
No - so I know.
I pasted in a number of educational articles for you, including the chemistries involved. This know-how is in the public domain, you just need to understand what you're reading.
Here's a link regarding the production of pale oils I mentioned just for you.
http://www.valero.com/products/pages/baseandprocessoils.aspx
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