Advanced Emulsifier Technology

hollandmarigoldOil and Offshore

Nov 8, 2013 (3 years and 11 months ago)

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enewable resource metalwork-
ing fluids are gaining more at -
tention in the marketplace
and for good reason. Metalworking flu -
id pro ducers are looking for more ef -
fective technologies to increase pro-
ductivity and reduce downtime – with-
out in creas ing costs. Changing regula-
tory re quirements are driving the de -
velop ment of products with reduced
environmental impact. At the same
time, in creasing concerns about work-
ers’ health and safety are putting pres-
sure on the industry to develop better
solutions.
Renewable resource products based
on vegetable oils offer an effective al -
ternative to traditional petroleum-
based products.
Market Drivers
The number one market driver for veg-
etable-oil technology? It works.Polar
veg etable oils are more effective lubri-
cants than non-polar petroleum-based
oils. And that can translate into im -
proved part quality and surface finish,
optimized tool life and potentially low -
er total fluid consumption. Because the
technology is so effective, fewer chem-
icals are needed, reducing costs and
the amount of fluid introduced into the
environment, an important considera-
tion in today’s market, where the push
is on to create a more environmentally
responsible metalworking fluid.
End users, such as workers’ unions
and major manufacturers, perceive that
renewable resource products offer an
improved health, safety and environ-
mental profile when compared with
tra ditional petroleum options. Gov ern -
men tal preference programs, in clud -
ing tax incentives and preferred pro-
curement programs, provide an addi-
tional incentive to move toward veg-
etable oil-based metalworking fluids.
A final potential market driver mov-
ing vegetable oils to the forefront is
Advanced Emulsifier Technology
For Renew able Resource-Based Metalworking Fluids
By Jennifer Ineman,Product Manager, Metal Processing, The Lubrizol Corporation
The Lubrizol Corporation
The above shows the relative composition of three common vegetable types considered for industrial
applications: canola oil (common in North America); rapeseed oil (common in Europe); and soybean oil
(common in North America).
Vegetable Oil Properties
Tests formulations – with no added defoamer at 5% dilution in water – were run for five minutes in a
recirculating pump with readings taken every 30 seconds. The pump was shut off after five minutes, but
readings continued for the next five minutes. The low foam performance of the vegetable-based oil with
the Lubrizol MC944V emulsifier is clearly shown.
Foam Performance
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economics. Historically, refined vege -
table oils have held substantially high-
e
r market price levels than their petro-
leum base stock counterparts; howev-
er, this price spread has narrowed in re -
cent years. For the first time, the eco-
nomics of switching to vegetable oils
are workable.
Market Challenges
While it is generally accepted that veg-
etable oils can outperform petroleum-
based products in many areas, usage
is sues still remain that limit their ap -
plication. First on the list: formulation
challenges. Emulsification is more dif-
ficult with vegetable oils, which re quire
a lower hydrophilic-lipophilic balance
(HLB), resulting in the need for more
and stronger emulsifiers. Natural oils
are also more susceptible to hydrolysis,
a condition that is accelerated by the
alkaline nature of metalworking fluids.
And during machining, it is inevitable
that metal ions will be introduced to the
fluid, which speeds up the process of ox -
idation. These issues are certainly not
in surmountable and can be ad dressed
with the appropriate fluid technologies.
Another challenge to additive sup-
pliers is fluid formulators’ and end
users’ high level of comfort with the
status quo. The “if it’s not broken; don’t
fix it” mentality comes into play here.
End users have been working with
petroleum-based fluids for quite some
time, and they like and understand how
these products operate. Add in the fact
that, even with rising petroleum prices,
these products are still relatively inex-
pensive, and it becomes clear that end
users will need a compelling reason to
make a change.
Not all Vegetable Oils are the
Same
Although there will be variations be -
tween Group I, II or III basestocks, for
the most part, naphthenic and paraf-
finic minerals are similar in nature.
This is not true when it comes to veg-
etable oils. Canola oil, rapeseed oil and
soybean oil will all behave differently.
That’s why an understanding of the
oil’s fatty acid composition and its like -
ly impact on product stability and du -
rability is essential.
In particular, the amount and type
of unsaturated fatty acids (double
bonds per carbon chain) is critical to
the oxidative stability of the oil. Fully
saturated carbon chains, like those
found in petroleum-based oils, are
ideal for oxidative stability, but the
high degree of saturation can result in
less fluidity, especially at lower tem-
peratures. Canola oil, containing pri-
marily monounsaturated fatty acid
chains, is the easiest vegetable oil for
formulation; rapeseed oil, with its long -
er carbon chain is slightly more chal-
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The vegetable oil formulated with Lubrizol MC944V delivered relative efficiency results 88% greater than
the industry standard mineral-based fluid.
Lubricity Performance: Microtap 6061 Aluminum
In this test, traditional mineral oils are diluted at 10%. The vegetable oil, diluted at 10%, delivered a 50%
increase in efficiency over mineral-based oil. When diluted at 5% (not possible with mineral oils) the
vegetable oils still delivered a 40% increase in efficiency. The result: vegetable-based oils deliver more
parts at half the cost.
Lubricity Performance: Microtap 1018 Steel
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lenging to emulsify; and soybean oil,
with high levels of polyunsaturation, is
best reserved for applications where
expectations for long emulsion service
l
ife are low. Another option is the use of
synthetic esters in place of the vege -
table oils. These esters offer the formu-
lator a more predictable, controlled
structure. Oxidation can still be an is -
sue, but emulsification is easier, and
properly designed esters are the best
option for avoiding polyunsaturation.
Current Vegetable Emulsifier
Technologies
There are a number of drawbacks to
currently available vegetable emulsifi-
er technologies, starting with high treat
rates – often in the 35 to 40 percent
range – compared to 15 to 20 percent
in a typical mineral oil formulation. As
a result, formulations require twice as
much of a more expensive product,
and using more emulsifier can result
in high foaming tendency. In addition,
many emulsifier technologies have
limited flexibility across different oils.
Attaining the desired pH range (9 to
9.5) is also a problem. Vegetable oils in
general are not tolerant of alkalinity.
Adding amine can cause them to be -
come hazy and makes stable concen-
trates with good emulsification prop-
erties difficult to achieve. To address
the alkalinity challenge, many manu-
facturers employ a “two-phase” system.
One phase contains the oil/emulsifier
combination, while another contains
water-soluble alkaline builders so that
oil and alkalinity can be kept separate-
ly. The two phases are both added to a
working system, a difficult process that
requires careful measurement and mon -
itoring practices. The result is added
complexity for the end user, increasing
the possibility of operator error.
Introducing Lubrizol® MC944V
Lubrizol MC944V was designed to ad -
dress many of the issues seen in cur-
rently available vegetable oil emulsifi-
er technologies. In particular, this is a
“one phase” product offering excep-
tional emulsification across a range of
vegetable oils and esters, with finished
products providing natural lubricity.
Lubrizol MC944V is effective at low
treat rates and capable of building al -
kalinity and pH levels for improved
emulsion durability. It also produces
in herently low foaming emulsions.
Testing Confirms Performance
To demonstrate the benefits of
Lubrizol MC944V, Lubrizol conducted
foam and lubricity performance test-
ing. Formulations for both sets of tests
consisted of 20% Lubrizol MC944V in
high oleic canola and 18% industry
standard package in naphthenic min-
eral-based oil.
Low Foaming:As fluids are forced
into smaller sumps at higher speeds,
foaming occurs and fluid can spill out
of the sump. Excessive foaming can al -
so have an impact on the lubricity of
the formulation. Defoamers are usually
recommended with metalworking fluid
to combat the negative effects of foam,
but they can be filtered out and need to
be replenished. Because it is built from
a low foaming ester, little or no de foam -
er is necessary in products formulated
with Lubrizol’s MC944V emulsifier.
Lubricity: The lubricity of the veg-
etable oil formulated with Lubrizol
MC944V was measured against the
standard mineral-based oils. Microtap
tests in aluminum and steel, run on a
customized program, demonstrate the
clear advantages of vegetable-based
metalworking fluids.
Biological Resistance: An industry
perception exists that vegetable oil-
based emulsion products are inher-
ently more subject to attack by bacte-
ria and fungus than comparable petro-
leum oil products. In reality, laborato-
ry testing has shown that vegetable
emulsion products built from Lubrizol
MC944V show a similar degree of at -
tack and degradation from microor-
ganisms as a petroleum-based prod-
uct, when no biocide is incorporated.
When an appropriate biocide is used,
the vegetable oil emulsion shows ex -
tended protection from microbial
growth and fluid degradation.
Addressing the Needs of the
Marketplace
Lubrizol MC944V was designed in
response to the market demand for
renew able resource metalworking flu-
ids. Tests prove that vegetable oil
emulsions can be technically and eco-
nomically viable. Based on a unique
combination of emulsifier chemistries,
MC944V addresses the specific chal-
lenges of the end market, providing ex -
ceptional emulsification in a wide range
of vegetable oils and esters.

The Lubrizol Corporation
(continued)
A modified ASTM E 2275 test was extended beyond the standard 12 day run to nine weeks. Unprotected,
the vegetable oil and mineral oil acted in a similar way, with the mineral oil failing before the vegetable
oil. The vegetable oil with the biocide was still in good working order after nine weeks.
pH Longevity








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