276 Lubricant Additives: Chemistry and Applications
Lubrizol, United States
Miracema Nuodex, Brasil
PCAS, France
Rhein Chemie, GermanyAdditionally, there are some lubricant manufacturers who still sulfurize dark-colored products for
their own use, and some local sulfurization plants also sulfurize commodity-type products.
9.6.2 MARKETERS
In general, the manufacturers are also marketing the products. Some local manufacturers buy sulfu-
rized products, blend them with esters, mineral oil, etc., and sell them under their own brand name.
Sulfur carriers are intermediate and not consumer products.
9.6.3 ECONOMICS
Market prices vary depending on the raw materials, the production process, and the performance
level of the products. Low-quality, dark sulfurized fats with distinct odor and limited stability sell
for less than U.S.D 1.6/kg. High-performance, top-quality, low-odor, light-color products achieve
prices of more than U.S.D 4.0/kg. Not only the raw materials, but much more the production pro-
cess, determine the price for a sulfurized product. For example, the sulfurization of a typical gear
oil sulfur carrier with di-sulfur-di-chloride and the necessary subsequent washing steps are more
costly than the sulfurization of a fat with fl ower of sulfur.
9.6.4 GOVERNMENT REGULATIONS
9.6.4.1 Competitive Pressures
There are no government regulations concerning the use of sulfurized products, but depending on
the location of the manufacturing plant, very stringent regulations and conditions concerning emis-
sion standards can apply. Therefore, there is a competitive distortion in production between more
and less environmentally aware countries. Production technology and in particular low-emission
production are key cost factors.
9.6.4.2 Product Differentiation
Apart from some commodities, there is a clear product differentiation mainly derived from qual-
ity and performance. A fi rst criterion for differentiation is color, followed by sulfur content, raw
materials, and odor. A classifi cation is hardly possible because many of the products are tailor-made
either to cover a specifi c performance profi le or to meet specifi cations in various applications. A
simple categorization by sulfur content or raw material bases would be to coarse and would not take
performance into account. Even products based on the same raw materials but manufactured with a
different process can be completely different in performance.
Modern, light-colored, high-performance products with low odor are sulfurized using H 2 S or
mercaptans. Even the appearance distinguishes these products from conventionally sulfurized dark-
colored, smelly products.
9.7 OUTLOOK
9.7.1 CRANKCASE/AUTOMOTIVE APPLICATIONS
Steady demands on the reduction of phosphorus levels in motor oils as well as requirements for
increased fuel effi ciency, that is, friction reduction will open new opportunities for sulfur chemistry.
Sulfurized products are already used in this type of application (see Section 9.5.3.6).