Historically, or at least into the 70’s, fuels such as diesel were considered to have adequate inherent
lubricity for their use in engines without any additional lubricity improver’s.
This all began to change when Sulphur Oxides in exhaust gases were targeted for reduction as part
of the campaign to reduce harmful emissions, which rolled out globally and to this day, continue to
increase in severity. This is achieved primarily by reducing the sulphur content in the fuel itself and is
carried out at the refinery level.
The processes used to reduce the sulphur content in the fuel, further reduced the lubricity, due to
their effect on the properties of other constituents of the fuel. This essentially amplified the
worsening of lubricity caused by reducing the sulphur content.