Fuels, hydraulic fluids and lubricants made of or comprising a portion of renewable hydrocarbon raw materials, as well as biodegradable fuels, hydraulic fluids and lubricants are known to support microbial growth. Highly toxicorganic biocides have been added to reduce microbial growth. The use of such biocides can now be avoided, by instead using a stable solution of boric acid in a solvent, the boric acid being completely dissolved or at least free from any particles larger than 100 nm in size, and adding this solution to the fuel, hydraulic fluid or lubricant to give a final concentration of boron in the range of 1-100 ppm, preferably 1-50 ppm in the product. While preventing microbial growth, the addition of boron also reduces corrosion, in particular microbiologically induced corrosion (MIC).

Fuels, hydraulic fluids and lubricants made of or comprising a portion of renewable hydrocarbon raw materials, as well as biodegradable fuels, hydraulic fluids and lubricants are known to support microbial growth. Highly toxicorganic biocides have been added to reduce microbial growth. The use of such biocides can now be avoided, by instead using a stable solution of boric acid in a solvent, the boric acid being completely dissolved or at least free from any particles larger than 100 nm in size, and adding this solution to the fuel, hydraulic fluid or lubricant to give a final concentration of boron in the range of 1-100 ppm, preferably 1-50 ppm in the product. While preventing microbial growth, the addition of boron also reduces corrosion, in particular microbiologically induced corrosion (MIC).

Methods are provided for producing Group III base stocks having high viscosity and also having one or more properties indicative of a high quality base stock. The resulting Group III base stocks can have a viscosity at 100 C. and/or a viscosity at 40 C. that is greater than the corresponding viscosity for a conventional Group III base stock. Additionally, the resulting Group III base stocks can have one or more properties that are indicative of a high quality base stock.

Methods are provided for producing Group III base stocks having high viscosity and also having one or more properties indicative of a high quality base stock. The resulting Group III base stocks can have a viscosity at 100 C. and/or a viscosity at 40 C. that is greater than the corresponding viscosity for a conventional Group III base stock. Additionally, the resulting Group III base stocks can have one or more properties that are indicative of a high quality base stock.

Methods are provided for producing Group I base stocks having high viscosity and also having one or more properties indicative of a high quality base stock. The resulting Group I base stocks can have a viscosity at 100? C. and/or a viscosity at 40? C. that is greater than the corresponding viscosity for a conventional Group I bright stock formed by solvent processing. Additionally, the resulting Group I base stocks can have one or more properties that are indicative of a high quality base stock.

Methods are provided for producing Group I base stocks having high viscosity and also having one or more properties indicative of a high quality base stock. The resulting Group I base stocks can have a viscosity at 100? C. and/or a viscosity at 40? C. that is greater than the corresponding viscosity for a conventional Group I bright stock formed by solvent processing. Additionally, the resulting Group I base stocks can have one or more properties that are indicative of a high quality base stock.

Methods are provided for producing Group II base stocks having high viscosity and also having one or more properties indicative of a high quality base stock. The resulting Group II base stocks can have a viscosity at 100? C. and/or a viscosity at 40? C. that is greater than the corresponding viscosity for a conventional Group II base stock. Additionally, the resulting Group II base stocks can have one or more properties that are indicative of a high quality base stock.

Methods are provided for producing Group II base stocks having high viscosity and also having one or more properties indicative of a high quality base stock. The resulting Group II base stocks can have a viscosity at 100? C. and/or a viscosity at 40? C. that is greater than the corresponding viscosity for a conventional Group II base stock. Additionally, the resulting Group II base stocks can have one or more properties that are indicative of a high quality base stock.

A low-friction coating includes: an aliphatic hydrocarbon group showing a peak in a region of 2,900 cm.sup.1 to 3000 cm.sup.1 in an infrared absorption spectrum; a carbonyl group showing a peak in a region of 1,650 cm.sup.1 to 1,800 cm.sup.1 in an infrared absorption spectrum; an aromatic component (C.sub.7H.sub.7.sup.+) showing a peak at mass 91.1 in a positive ion spectrum obtained by TOF-SIMS; and a condensed ring based component (C.sub.9H.sub.7.sup.+) showing a peak at mass 115.2 in the positive ion spectrum obtained by TOF-SIMS.

A low-friction coating includes: an aliphatic hydrocarbon group showing a peak in a region of 2,900 cm.sup.1 to 3000 cm.sup.1 in an infrared absorption spectrum; a carbonyl group showing a peak in a region of 1,650 cm.sup.1 to 1,800 cm.sup.1 in an infrared absorption spectrum; an aromatic component (C.sub.7H.sub.7.sup.+) showing a peak at mass 91.1 in a positive ion spectrum obtained by TOF-SIMS; and a condensed ring based component (C.sub.9H.sub.7.sup.+) showing a peak at mass 115.2 in the positive ion spectrum obtained by TOF-SIMS.