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Commonly Asked Questions on Hydrocracked Base Oils

Why should I use Hydrocracked base oils?

Hydrocracked base oils offer superior product performance, resulting in greater oxidation and thermal stability, soot dispersancy in Heavy Duty Motor Oils, and low temperature performance. In addition to these benefits, hydrocracked base oils also have high VI and low volatility.

Hydrocracked base oils can be formulated with a wide variety of additives either to achieve the latest industry specifications or simply to produce premium performance lubricants.

Hydrocracked base oils can help to meet challenging future lubricant specifications cost-effectively, whereas Group I oils often cannot. Hydrocracked base oils are especially valuable where they can replace traditional synthetic base oils to achieve synthetic performance.

What do Group I, II, and III mean, and what's so great about Group II and Group III?

Groups I, II, and III are broad categories of base stocks developed by the American Petroleum Institute (API) for the purpose of creating guidelines for licensing engine oils. Typically, solvent-refined base oils fall into Group I, while hydro processed base stocks fall into Group II. Unconventional Base Oils (UCBOs) or Very-High VI stocks are normally categorized as Group III.

Group I oils contain high levels of sulphur and aromatics, which are compounds that can diminish performance. Group II oils have lower levels of these impurities, which result in enhanced oxidation performance for fully-formulated lubricants. With hydrodewaxing technology, Group II II base oils have low-wax composition, which delivers improved low-temperature performance compared to conventional Group I base oils.

Due to their high level of purity, Group II base oils provide additional benefits in crankcase applications. For example, in heavy-duty engines, motor oils made with Group II & III base oils have demonstrated a soot dispersancy markedly higher than those made with conventional base oils. They have also demonstrated potential for greater fuel economy in passenger car engine oils.

What makes Group II base oils more resistant to oxidation?

Group II base oils contain lower levels of reactive compounds compared to solvent-refined Group I base oils. These "impurities," which include aromatics and sulphur compounds, are much more susceptible to oxidative attack. Once these compounds begin to oxidize, a complex chain of reactions occurs that ultimately causes both the base oil and the additive to degrade. The virtual absence of these impurities means Group II base oils deliver exceptional resistance to oxidation.

Are Group II Base Oils synthetic?

A recent ruling from a respected advertising self-regulatory body decided a case on the use of the term synthetic. It found that synthetic base stocks are not limited to PAOs. The decision said that the key requirement for calling a base stock synthetic is that it be the result of conversion or processing of one complex mixture. Group II base oils clearly meet the test.

Are Group II base oils better for the environment?

Yes. Group II base oils have low toxicity as measured by eye and skin irritation, inhalation, and oral and dermal toxicity tests. They are neither mutagenic nor carcinogenic, as indicated by their performance in the modified Ames test and IP346 polycyclic aromatic test. In fact, these base oils are so pure, they meet the requirements of FDA-approved mineral oils (21CFR 178.3620(c)). This means that Group II base oils can be used in or used to manufacture a variety of non-food articles intended for incidental contact with food.

Characteristic & Significant Difference

COLOUR - Hydrocracked base oils are clear and colourless
VISCOSITY INDEX - Hydrocracked base oils have higher VIs so they 'thin-out' less at high temperatures than Solvent Refined oils.
OXIDATION RESISTANCE - Hydrocracked base oils respond very well to anti-oxidants and so have superior resistance to oxidation and a longer lubricant life.
THERMAL STABILITY - Hydrocracked base oils have considerably better resistance to heat than Solvent Refined oils.
CARBON RESIDUE - Hydrocracked base oils produce lower residues than Solvent Refined oils.
DEMULSIBILITY - Hydrocracked oils separate easier from water than Solvent Refined oils
LOW TOXICITY - Hydrocracked base oils have low toxicity, due to a virtual absence of impurities.
BIODEGRADABILITY - Hydrocracked base oils biodegrade faster than Solvent Refined oils - 60% vs 30%, as measured by the CEC-L33-A-93 test.