Thermogravimetric Analysis

Internal combustion in engines produces soot as a result of incomplete fuel combustion. High levels of soot content in oil leads to a higher lubricant viscosity impeding oil flow as well as carbon deposition in the piston ring. It will also affect anti-wear lubricant additives resulting in increased engine wear and premature engine failures. As a result, soot content monitoring is an important parameter for engine oil. An aliquot of sample is weighed in a TGA balance and heated up to 650 °C in a nitrogen environment, to remove all the volatiles and other organic materials. The environment is then changed to oxygen at 650 °C to burn off the soot. The soot content is determined by the difference observed in weight from oxygen switch over until stable weight residue or unchanged weight loss is observed for 5 minutes or longer.