Luis Bastardo-Zambrano Lubricants Russia – Use of Super Heavy Naphthenics in Lubricant Formulations Luis Bastardo-Zambrano, PhD Nynas Naphthenics AB Nynashamn, Sweden

Luis Bastardo-Zambrano Lubricants Russia – Outline  Introduction: Base Oil Market Overview  Bright Stocks  Super heavy naphthenic oil (Naphthenic 4000) and Polyisobutenes: Film Strength Thickening Effect Tackiness Shear Stability

Luis Bastardo-Zambrano Lubricants Russia – Base Oil Market Overview  Base stock supply is estimated at barrels/day more than half Group I  Global demand may increase by 6% by 2010 (34% of it in the Asia/Pacific region)^  Shift to higher quality oil worldwide (Group II and Group III)  Detriment of Group I production, especially bright stocks  Bright stocks output fell by 8% between Group I shut downs, will bring down bright stocks production by 10% in the next 10 years.* *Tocci, L. High stakes for base oils. Lubes´n´Greases. Vol.13 (1) ^ DeMarco, N. Total’s Take on Base Oil Balances. Lube Report. February *

Luis Bastardo-Zambrano Lubricants Russia – Bright Stocks  High viscosity base oils refined from paraffinic crude  Mainly use is:  Marine oils  Monograde motor oils  Gear oils  Greases  Other products  Possible substitutions:  PIB (Polyisobutene)  PAO (Polyalphaolefins)  Heavy Naphthenics

Luis Bastardo-Zambrano Lubricants Russia – Super Heavy Naphthenic Oil  The Super Heavy Naphthenic Oil used in this work (Naphthenic 4000) is a product with a very high viscosity (4800 cSt at 40°C) and excellent solvent power (aniline point 80°C)  Naphthenic 4000 can be used as additive in gear oils, metalworking fluids, greases and oil treatment as well as in blends with lower viscosity naphthenic oils to obtain naphthenic bright stocks  It displays interesting properties such as  Very good shear stability  High film strength  High tackiness  Very low carbon residue (<0.10%) Naphthenic 4000

Luis Bastardo-Zambrano Lubricants Russia – Tests on Naphthenic 4000  The super-heavy naphthenic oil Naphthenic 4000 was compared with several commercial PIBs presenting different molecular weight  The following properties were tested  Film strength  Thickening effect  Tackiness  Shear stability

Luis Bastardo-Zambrano Lubricants Russia – Main Properties of the PIBs Tested CharacteristicsMethodPIB APIB BPIB CPIB D Number average molecular weightGPC °C (cSt)ASTM D °C (cSt)ASTM D °C (g/cm3)DIN Pour point (°C)ASTM D Flash point (°C)ASTM D

Luis Bastardo-Zambrano Lubricants Russia – Film Strength - Method  Film strength: Ability of a lubricant to withstand the effects of load  Method used: ASTM D2783 (Four-Ball Test). Upper ball under load and rotating (speed 1760 ± 40 rpm)  Film strength given by initial seizure  Materials tested: Naphthenic 4000, PIB A and PIB D Naphthenic 4000 Film Strength = 2 x PIB A Film Strength Naphthenic 4000 Film Strength 50% higher than PIB B’s

Luis Bastardo-Zambrano Lubricants Russia – Thickening Effect - Method  Increasing amounts of Naphthenic 4000 and the PIB having the same viscosity (PIB A) were added to the naphthenic oil Base oil 400  Treating rates of 10, 20, 30, 40, 50, 60, 70, 80 and 90% were used  After each addition, the viscosity of the blend was measured by ASTM D 445  A viscosity curve was obtained for each thickener

Luis Bastardo-Zambrano Lubricants Russia – Thickening Effect – Results and Discussion (1) Naphthenic 4000

Luis Bastardo-Zambrano Lubricants Russia – Thickening Effect – Results and Discussion (2)  The PIB A has a more marked thickening effect compared to the Naphthenic 4000  The difference in viscosity becomes evident at additions above 30% treating rates  The difference is most pronounced at high treating rates (> 60%)

Luis Bastardo-Zambrano Lubricants Russia – Tackiness - Method  Tackiness is defined as the resistance to flow in extension and is a combination of cohesivity and adhesivity  The tackiness was measured in a filament break-up rheometer  The test fluid is placed between two cylindrical test fixtures (rheometer plates) and is submitted to an axial step-strain applied generating the formation of an elongated liquid thread

Luis Bastardo-Zambrano Lubricants Russia – The Capillary Break-Up Extensional Rheometer: Filament Formation Axial strain d0d0 D D dfdf D D

Luis Bastardo-Zambrano Lubricants Russia – Tackiness Tests – Experimental Conditions  Naphthenic 4000 and four PIBs were added to the naphthenic oils Base oil 400 and Base oil 110  Treating rates of 0.5 % and 1.5 % were used  The time evolution of the filament diameter for the pure and additivated oils was followed  The final gap between the rheometer plates was set to 8 mm for the tests performed on Base oil 400 and to 6 mm for the tests carried out on Base oil 110  The final gap between the plates must be kept constant through a series of experiments as it is directly correlated to the deformation to which the material is submitted during the test

Luis Bastardo-Zambrano Lubricants Russia – Tackiness Tests on Base Oil 110 with 1.5% Treating Rate

Luis Bastardo-Zambrano Lubricants Russia – Tackiness Tests – Results and Discussion  Naphthenic 4000 gave a tackiness increase equal to that given by the PIB B (having a viscosity at 40°C of 7750 cSt)  Increasing the treating rate has a positive effect both for Naphthenic 4000 and the PIB B. The effect is more marked with Base oil 110.  As expected, the tackifying effect of the PIBs increases with increasing molecular weight.  Nevertheless, the higher the molecular weight of the PIBs, the higher the sensitivity to shearing forces.

Luis Bastardo-Zambrano Lubricants Russia – Shear Stability Tests - Method  Method used: CEC L 45-A-99 (Viscosity shear stability of transmission lubricants – Tapered roller bearing rig)  The bearing is loaded axially with 5000 N, rotated at 1475 rev/min and maintained at a temperature of 60°C.  The viscosity of the fluid before and after the test was measured using the method DIN The result: % of viscosity lost by the fluid The polymer molecules break when submitted to high shear stresses

Luis Bastardo-Zambrano Lubricants Russia – Conclusions  Worldwide production of base oils is shifting to higher quality products, Group II and III base oils  These changes may cause shortage of Bright Stocks in the market  Heavy naphthenic oils and PIBs are alternatives available right now  The super heavy naphthenic oil Naphthenic 4000 outperforms PIBs in properties such as film strength and shear stability  Conversely, the thickening effect of PIBs is higher than that of the Naphthenic 4000  The impact on tackiness of Naphthenic 4000 is comparable to that of the medium molecular weight PIBs, while high molecular weight PIBs show a more marked tackifying effect